Technology Preview: RESTful Volume Management with Heketi

Heketi provides a RESTful management interface for managing Red Hat Gluster Storage volume life cycles. This interface allows cloud services like OpenStack Manila, Kubernetes, and OpenShift to dynamically provision Red Hat Gluster Storage volumes. For details about this technology preview, see the Red Hat Gluster Storage 3.1 Administration Guide: https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Administration_Guide/ch06s02.html.

Tiering

Red Hat Gluster Storage now provides the ability to automatically classify and migrate files based on how frequently those files are accessed. This allows frequently accessed files to be migrated to higher performing disks (the hot tier), and rarely accessed files to be stored on disks with lower performance (the cold tier). This enables faster response times, reduced latency, greater storage efficiency, and reduced deployment and operating costs. For more information about tiering, see the Red Hat Gluster Storage 3.1 Administration Guide: https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Administration_Guide/chap-Managing_Data_Tiering.html.

Writable Snapshots

Red Hat Gluster Storage snapshots can now be cloned and made writable by creating a new volume based on an existing snapshot. Clones are space efficient, as the cloned volume and original snapshot share the same logical volume back end, only consuming additional space as the clone diverges from the snapshot. For more information, see the Red Hat Gluster Storage 3.1 Administration Guide: https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Administration_Guide/.

Red Hat Gluster Storage for Containers

As of Red Hat Gluster Storage 3.1 Update 2, Red Hat Gluster Storage can now be set up in a container on either Red Hat Enterprise Linux Atomic Host 7.2 or Red Hat Enterprise Linux Server 7.2. Containers use the shared kernel concept and use system resources more efficiently than hypervisors. Containers rest on top of a single Linux instance and allow applications to use the same Linux kernel as the system that they are running on. This improves the overall efficiency of the system and reduces space consumption.

BitRot scrubber status

The BitRot scrubber command (gluster volume bitrot VOLNAME scrub status) can now display scrub process statistics and list identified corrupted files, allowing administrators to locate and repair corrupted files more easily. See the Red Hat Gluster Storage 3.1 Administration Guide for details: https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Administration_Guide/chap-Detecting_Data_Corruption.html.

Samba Asynchronous I/O enabled by default

Red Hat Gluster Storage now supports and enables asynchronous I/O with Samba by default (aio read size = 4096). Asynchronous I/O can enable increased throughput on multi-threaded clients, or when multiple programs access the same share. This improves default performance for most users of Samba and Red Hat Gluster Storage.

Console Virtual Appliance

Red Hat Gluster Storage Console now provides a virtual appliance that can be used to quickly set up a pre-installed and partially configured Red Hat Gluster Storage Console. This also enables offline installation of the Red Hat Gluster Storage Console on virtual machines managed by Red Hat Enterprise Virtualization Management. See the Red Hat Gluster Storage 3.1 Console Installation Guide for details: https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Console_Installation_Guide/chap-Red_Hat_Storage_Console_Installation-OVA.html

Hortonworks Data Platform (HDP)

Support for Hortonworks Data Platform (HDP) on Red Hat Gluster Storage integrated using the Hadoop Plug-In is deprecated as of Red Hat Gluster Storage 3.1 Update 2, and is unlikely to be supported in the next major release. Red Hat discourages further use of this plug-in for deployments where Red Hat Gluster Storage is directly used for holding analytics data for running in-place analytics. However, Red Hat Gluster Storage can be used as a general purpose repository for holding analytics data and as a companion store where the bulk of the data is stored and then moved to Hadoop clusters for analysis when necessary.

CTDB 2.5

As of Red Hat Gluster Storage 3.1 Update 2, CTDB version 2.5 is no longer supported. To continue using CTDB in Red Hat Gluster Storage 3.1 Update 2 and later, upgrade to CTDB version 4, provided in the following channels and repositories:

• RHN channel for Red Hat Enterprise Linux 6: rhel-x86_64-server-6-rh-gluster-3-samba
• RHN channel for Red Hat Enterprise Linux 7: rhel-x86_64-server-7-rh-gluster-3-samba
• Subscription Management repository for Red Hat Enterprise Linux 6: rh-gluster-3-samba-for-rhel-6-server-rpms
• Subscription Management repository for Red Hat Enterprise Linux 7: rh-gluster-3-samba-for-rhel-7-server-rpms

Issues related to Containers

BZ#1294776

When a container with one or more logical volumes bind-mounted as bricks is started in Atomic Host, the logical volumes are sometimes unmounted from Atomic Host during container start. This causes problems when the container is re-spawned.

Workaround: After starting the Red Hat Gluster Storage container, verify that the mount point is still mounted in the Atomic Host by checking the output of df -h. If the mount point is not mounted, ensure that it is configured in /etc/fstab and remount it on Atomic Host by running mount -a.

Issues related to Tiering

BZ#1294790 , BZ#1294808

Currently, the tier process performs a fix-layout operation on the entire volume every time it starts. Tier migration operations only begin after the fix-layout operation is complete. This means that in some circumstances, such as when extremely large amounts of data are present on the volume immediately before tiering is enabled, the fix-layout operation can take a long time to complete and prevents file promotion to the hot tier until after the fix-layout operation has completed.

BZ#1303298

When a readdirp call is performed on a USS (User Serviceable Snapshot) as part of a request to list the entries on a snapshot of a tiered volume, the USS provides the wrong stat for files in the cold tier. This results in incorrect permissions being applied to the mount point, and files appear to have -----T permissions.

Workaround: FUSE clients can work around this issue by applying any of the following options:

• use-readdirp=no (recommended)
• attribute-timeout=0
• entry-timeout=0

NFS clients can work around the issue by applying the noac option.

BZ#1300679

If the hot and cold tiers in a tiered volume have the same number of sub-volumes, the first group of files migrated in a single cycle is likely to be migrated to the same sub-volume on the hot tier rather than being distributed across multiple sub-volumes. This is particularly noticeable when the files that are candidates for migration exceed the number defined by tier-max-files or the size defined by tier-max-mb.

BZ#1302968

The defrag variable is not being reinitialized during glusterd restart. This means that if glusterd fails while the following processes are running, it does not reconnect to these processes after restarting:

• rebalance
• tier
• remove-brick

This results in these processes continuing to run without communicating with glusterd. Therefore, any operation that requires communication between these processes and glusterd fails.

Workaround: Stop or kill the rebalance, tier, or remove-brick process before restarting glusterd. This ensures that a new process is spawned when glusterd restarts.

BZ#1303045

When a tier is attached while I/O is occurring on an NFS mount, I/O pauses temporarily, usually for between 3 to 5 minutes. If I/O does not resume within 5 minutes, use the gluster volume start volname force command to resume I/O without interruption.

BZ#1273741

Files with hard links are not promoted or demoted on tiered volumes.

BZ#1305490

A race condition between tier migration and hard link creation results in the hard link operation failing with a 'File exists' error, and logging 'Stale file handle' messages on the client. This does not impact functionality, and file access works as expected.

This race occurs when a file is migrated to the cold tier after a hard link has been created on the cold tier, but before a hard link is created to the data on the hot tier. In this situation, the attempt to create a hard link on the hot tier fails. However, because the migration converts the hard link on the cold tier to a data file, and a linkto already exists on the cold tier, the links exist and work as expected.

BZ#1277112

When hot tier storage is full, write operations such as file creation or new writes to existing files fail with a 'No space left on device' error, instead of redirecting writes or flushing data to cold tier storage.

Workaround: If the hot tier is not completely full, it is possible to work around this issue by waiting for the next CTR promote/demote cycle before continuing with write operations.

If the hot tier does fill completely, administrators can copy a file from the hot tier to a safe location, delete the original file from the hot tier, and wait for demotion to free more space on the hot tier before copying the file back.

BZ#1278391

Migration from the hot tier fails when the hot tier is completely full because there is no space left to set the extended attribute that triggers migration.

BZ#1283507

Corrupted files can be identified for promotion and promoted to hot tier storage.

In rare circumstances, corruption can be missed by the BitRot scrubber. This can happen in two ways:

1. A file is corrupted before its checksum is created, so that the checksum matches the corrupted file, and the BitRot scrubber does not mark the file as corrupted.
2. A checksum is created for a healthy file, the file becomes corrupted, and the corrupted file is not compared to its checksum before being identified for promotion and promoted to the hot tier, where a new (corrupted) checksum is created.

When tiering is in use, these unidentified corrupted files can be 'heated' and selected for promotion to the hot tier. If a corrupted file is migrated to the hot tier, and the hot tier is not replicated, the corrupted file cannot be accessed or migrated back to the cold tier.

BZ#1283957

When volume status or volume tier status is requested for a tiered volume, the status of all nodes in the storage pool is listed as in progress, even when a node is not part of the tiered volume. This occurs because the tier daemon runs on all nodes of the trusted storage pool, and reports status for every volume in the trusted storage pool.

Issues related to Snapshot

1306917

When a User Serviceable Snapshot is enabled, attaching a tier succeeds, but any I/O operations in progress during the attach tier operation may fail with stale file handle errors.

Workaround: Disable User Serviceable Snapshots before performing attach tier. Once attach tier has succeeded, User Serviceable Snapshots can be enabled.

BZ#1309209

When a cloned volume is deleted, its brick paths (stored under /run/gluster/snaps) are not cleaned up correctly. This means that attempting to create a clone that has the same name as a previously cloned and deleted volume fails with a Commit failed message.

Workaround: After deleting a cloned volume, ensure that brick entries in /run/gluster/snaps are unmounted and deleted, and that their logical volumes are removed.

BZ#1201820

When a snapshot is deleted, the corresponding file system object in the User Serviceable Snapshot is also deleted. Any subsequent file system access results in the snapshot daemon becoming unresponsive. To avoid this issue, ensure that you do not perform any file system operations on the snapshot that is about to be deleted.

BZ#1308837

When a tiered volume with quota enabled is snapshotted, and that snapshot is cloned, rebooting the node or restarting glusterd on the node can result in that node entering a peer rejected state. This occurs because the quota checksum is not being copied as part of the snapshot or clone operations.

Workaround:

1. Check glusterd logs for a quota checksum mismatch error, which looks similar to the following:

   E [MSGID: 106012] [glusterd-utils.c:2845:glusterd_compare_friend_volume] 0-management: Cksums of quota configuration of volume volname differ. local cksum = 1405646976, remote  cksum = 0 on peer peername

2. If the volume with this error is cloned, edit the /var/lib/glusterd/vols/volname/info file for that volume and increase the value in the version field by one.
3. Restart glusterd on the node.

BZ#1160621

If the current directory is not a part of the snapshot, for example, snap1, then the user cannot enter the .snaps/snap1 directory.

BZ#1169790

When a volume is down and there is an attempt to access .snaps directory, a negative cache entry is created in the Kernal Virtual File System (VFS) cache for the .snapsdirectory. After the volume is brought back online, accessing the .snaps directory fails with an ENOENT error because of the negative cache entry.

Workaround: Clear the kernel VFS cache by executing the following command:

# echo 3 > /proc/sys/vm/drop_caches

Note that this can cause temporary performance degradation.

BZ#1170145

After the restore operation is complete, if restore a volume while you are in the .snaps directory, the following error message is displayed from the mount point - "No such file or directory".

Workaround: Navigate to the parent directory of the .snaps directory and use the following command to drop the VFS cache:

# echo 3 > /proc/sys/vm/drop_caches

Then move back into the .snaps folder. Note that this command can cause temporary performance degradation.

BZ#1170365

Virtual inode numbers are generated for all the files in the .snaps directory. Any hard links are assigned different inode numbers instead of the same inode number.

BZ#1170502

When the User Serviceable Snapshot feature is enabled, if a directory or a file by name .snaps exists on a volume, it appears in the output of the ls -a command.

BZ#1174618

If the User Serviceable Snapshot feature is enabled, and a directory has a pre-existing .snaps folder, then accessing that folder can lead to unexpected behavior.

Workaround: Rename the pre-existing .snaps folder with another name.

BZ#1167648

Performing operations which involve client graph changes such as volume set operations, restoring snapshot, etc. eventually leads to out of memory scenarios for the client processes that mount the volume.

BZ#1133861

New snap bricks fails to start if the total snapshot brick count in a node goes beyond 1K. Until this bug is corrected, Red Hat recommends deactivating unused snapshots to avoid hitting the 1K limit.

BZ#1126789

If any node or glusterd service is down when snapshot is restored then any subsequent snapshot creation fails. Red Hat recommends not restoring a snapshot while the node or the glusterd service is unavailable.

BZ#1139624

While taking a snapshot of a gluster volume, Red Hat Gluster Storage creates another volume which is similar to the original volume. All volumes, including snapshot volumes, consume some memory when started. This can create an out of memory state when creating a snapshot on a system with low memory. Red Hat recommends deactivating unused snapshots to reduce the memory footprint of the system and avoid this issue.

BZ#1129675

Performing a snapshot restore while glusterd is not available in a cluster node or a node is unavailable results in the following errors:

• Executing the gluster volume heal vol-name info command displays the error message Transport endpoint not connected.
• Error occurs when clients try to connect to glusterd service.

Workaround: Perform snapshot restore only if all the nodes and their corresponding glusterd services are running. Start glusterd by running the following command:

# service glusterd start

BZ#1105543

When a node with old snap entry is attached to the cluster, the old entries are propagated throughout the cluster and old snapshots which are not present are displayed.

Workaround: Do not attach a peer with old snap entries.

BZ#1104191

The snapshot command fails if snapshot command is run simultaneously from multiple nodes when a large number of write or read operations are happening on the origin or parent volume.

Workaround: Avoid running multiple snapshot commands simultaneously from different nodes.

BZ#1059158

The NFS mount option is not supported for snapshot volumes.

BZ#1113510

Executing the gluster volume info command displays system limits (snap-max-hard-limit and snap-max-soft-limit) instead of volume limits, and also displays snapshot auto-delete values.

BZ#1111479

Attaching a new node to the cluster while snapshot delete was in progress appears to successfully delete snapshots, but the gluster snapshot list command shows some of the snapshots are still present.

Workaround: Do not attach or detach new node to the trusted storage pool operation while a snapshot is in progress.

BZ#1092510

If you create a snapshot when the rename of a directory is in progress (that is, renaming is complete on hashed sub-volume but not on all of the sub-volumes), on snapshot restore, directory which was undergoing rename operation will have same GFID for both source and destination. Having same GFID is an inconsistency in DHT and can lead to undefined behavior.

In DHT, a rename (source, destination) of directories is done first on hashed sub-volume and if successful, then on rest of the sub-volumes. At this point in time, if you have both source and destination directories present in the cluster with same GFID - destination on hashed sub-volume and source on rest of the sub-volumes. A parallel lookup (on either source or destination) at this time can result in creation of directories on missing sub-volumes - source directory entry on hashed and destination directory entry on rest of the sub-volumes. Hence, there would be two directory entries - source and destination - having same GFID.

BZ#1112250

Probing/detaching a new peer during any snapshot operation is not supported.

BZ#1236149

If a node/brick is down, the snapshot create command fails even with the force option.

BZ#1240227

LUKS encryption over LVM is currently not supported.

BZ#1236025

The time stamp of files and directories changes on snapshot restore, resulting in a failure to read the appropriate change logs. glusterfind pre fails with the following error: historical changelogs not available. Existing glusterfind sessions fail to work after a snapshot restore.

Workaround: Gather the necessary information from existing glusterfind sessions, remove the sessions, perform a snapshot restore, and then create new glusterfind sessions.

BZ#1160412

During the update of the glusterfs-server package, warnings and fatal errors appear on-screen by librdmacm if the machine does not have an RDMA device. If you do not require Gluster to work with RDMA transport, these errors can be safely ignored.

BZ#1246183

User Serviceable Snapshots is not supported on Erasure Coded (EC) volumes.

Issues related to Nagios

BZ#1136207

Volume status service shows All bricks are Up message even when some of the bricks are in unknown state due to unavailability of glusterd service.

BZ#1109683

When a volume has a large number of files to heal, the volume self heal info command takes time to return results and the nrpe plug-in times out as the default timeout is 10 seconds.

Workaround: In /etc/nagios/gluster/gluster-commands.cfg increase the timeout of nrpe plug-in to 10 minutes by using the -t option in the command. For example:

$USER1$/gluster/check_vol_server.py $ARG1$ $ARG2$ -o self-heal -t 600

BZ#1094765

When certain commands invoked by Nagios plug-ins fail, irrelevant outputs are displayed as part of performance data.

BZ#1107605

Executing sadf command used by the Nagios plug-ins returns invalid output.

Workaround: Delete the datafile located at /var/log/sa/saDD where DD is current date. This deletes the datafile for current day and a new datafile is automatically created and which is usable by Nagios plug-in.

BZ#1107577

The Volume self heal service returns a WARNING when there unsynchronized entries are present in the volume, even though these files may be synchronized during the next run of self-heal process if self-heal is turned on in the volume.

BZ#1121009

In Nagios, CTDB service is created by default for all the gluster nodes regardless of whether CTDB is enabled on the Red Hat Gluster Storage node or not.

BZ#1089636

In the Nagios GUI, incorrect status information is displayed as Cluster Status OK : None of the Volumes are in Critical State, when volumes are utilized beyond critical level.

BZ#1111828

In Nagios GUI, Volume Utilization graph displays an error when volume is restored using its snapshot.

BZ#1236997

Bricks with an UNKNOWN status are not considered as DOWN when volume status is calculated. When the glusterd service is down in one node, brick status changes to UNKNOWN while the volume status remains OK. You may think the volume is up and running when bricks may not be running. You are not able to detect the correct status.

Workaround: You are notified when gluster is down and when bricks are in an UNKNOWN state.

BZ#1240385

When the configure-gluster-nagios command tries to get the IP Address and FLAGs for all network interfaces in the system, the following error is displayed:

ERROR:root:unable to get ipaddr/flags for nic-name: [Errno 99] Cannot assign requested address when there is an issue while retrieving IP Address/Fags for a NIC.

However, the command actually succeeded and configured the nagios correctly.

Issues related to Rebalancing Volumes

BZ#1266874

Rebalance operation tries to start the gluster volume before doing the actual rebalance. In most of the cases, volume is already in Started state. If the volume is already started and the volume start command fails, gdeploy assumes that volume has started and does not start the rebalance process.

Workaround: Rebalance in gdeploy is possible only for stopped volumes.

BZ#1110282

Executing rebalance status command, after stopping rebalance process, fails and displays a message that the rebalance process is not started.

BZ#1140531

Extended attributes set on a file while it is being migrated during a rebalance operation are lost.

Workaround: Reset the extended attributes on the file once the migration is complete.

BZ#960910

After executing rebalance on a volume, running the rm -rf command on the mount point to remove all of the content from the current working directory recursively without being prompted may return Directory not Empty error message.

BZ#862618

After completion of the rebalance operation, there may be a mismatch in the failure counts reported by the gluster volume rebalance status output and the rebalance log files.

BZ#1039533

While Rebalance is in progress, adding a brick to the cluster displays an error message, failed to get index in the gluster log file. This message can be safely ignored.

BZ#1064321

When a node is brought online after rebalance, the status displays that the operation is completed, but the data is not rebalanced. The data on the node is not rebalanced in a remove-brick rebalance operation and running commit command can cause data loss.

Workaround: Run the rebalance command again if any node is brought down while rebalance is in progress, and also when the rebalance operation is performed after remove-brick operation.

BZ#1237059

The rebalance process on a distributed-replicated volume may stop if a brick from a replica pair goes down as some operations cannot be redirected to the other available brick. This causes the rebalance process to fail.

BZ#1245202

When rebalance is run as a part of remove-brick command, some files may be reported as split-brain and, therefore, not migrated, even if the files are not split-brain.

Workaround: Manually copy the files that did not migrate from the bricks into the Gluster volume via the mount.

Issues related to Geo-replication

BZ#1293634

Sync performance for geo-replicated storage is reduced when the master volume is tiered, resulting in slower geo-rep performance on tiered volumes.

BZ#1302320

During file promotion, the rebalance operation sets the sticky bit and suid/sgid bit. Normally, it removes these bits when the migration is complete. If readdirp is called on a file before migration completes, these bits are not removed, and remain applied on the client.

This means that, if rsync happens while the bits are applied, the bits remain applied to the file as it is synced to the destination, impairing accessibility on the destination. This can happen in any geo-replicated configuration, but the likelihood increases with tiering because the rebalance process is continuous.

BZ#1286587

When geo-replication is in use alongside tiering, bricks attached as part of a tier are incorrectly set to passive. If geo-replication is subsequently restarted, these bricks can become faulty.

Workaround: Stop geo-replication session prior to attaching or detaching bricks that are part of a tier.

To attach a tier:

1. Stop geo-replication:

   # gluster volume geo-replication master_vol slave_host::slave_vol stop

2. Attach the tier:

   # gluster volume attach-tier master_vol replica 2 server1:/path/to/brick1 server2:/path/to/brick2

3. Restart geo-replication:

   # gluster volume geo-replication master_vol slave_host::slave_vol start

4. Verify that bricks in tier are available in geo-replication session:

   # gluster volume geo-replication master_vol slave_host::slave_vol status

To detach a tier:

1. Begin the tier detachment process:

   # gluster volume detach-tier master_vol start

2. Ensure all data in that tier is synced to the slave:

   # gluster volume geo-replication master_vol slave_host::slave_vol config checkpoint now

3. Monitor checkpoint until displayed status is checkpoint as of time of checkpoint creation is completed at time.

   # gluster volume geo-replication master_vol slave_host::slave_vol status detail

4. Verify that detachment is complete:

   # gluster volume detach-tier master_vol status

5. Stop geo-replication:

   # gluster volume geo-replication master_vol slave_host::slave_vol stop

6. Commit tier detachment:

   # gluster volume detach-tier master_vol commit

7. Verify tier is detached:

   # gluster volume info master_vol

8. Restart geo-replication:

   # gluster volume geo-replication master_vol slave_host::slave_vol start

BZ#1102524

The Geo-replication worker goes to faulty state and restarts when resumed. It works as expected when it is restarted, but takes more time to synchronize compared to resume.

BZ#987929

While the rebalance process is in progress, starting or stopping a Geo-replication session results in some files not get synced to the slave volumes. When a Geo-replication sync process is in progress, running the rebalance command causes the Geo-replication sync process to stop. As a result, some files do not get synced to the slave volumes.

BZ#1029799

Starting a Geo-replication session when there are tens of millions of files on the master volume takes a long time to observe the updates on the slave mount point.

BZ#1027727

When there are hundreds of thousands of hard links on the master volume prior to starting the Geo-replication session, some hard links are not getting synchronized to the slave volume.

BZ#984591

After stopping a Geo-replication session, if the files synced to the slave volume are renamed then when Geo-replication starts again, the renamed files are treated anew, (without considering the renaming) and synced on to the slave volumes again. For example, if 100 files were renamed, you would find 200 files on the slave side.

BZ#1235633

Concurrent rmdir and lookup operations on a directory during a recursive remove may prevent the directory from being deleted on some bricks. The recursive remove operation fails with Directory not empty errors even though the directory listing from the mount point shows no entries.

Workaround: Unmount the volume and delete the contents of the directory on each brick. If the affected volume is a geo-replication slave volume, run stop geo-rep session before deleting the contents of the directory on the bricks.

BZ#1238699

The Changelog History API expects brick path to remain the same for a session. However, on snapshot restore, brick path is changed. This causes the History API to fail and geo-rep to change to Faulty.

Workaround:

1. After the snapshot restore, ensure the master and slave volumes are stopped.
2. Backup the htime directory (of master volume).

   cp -a <brick_htime_path> <backup_path>

   Note

   Using -a option is important to preserve extended attributes.
   For example:

   cp -a /var/run/gluster/snaps/a4e2c4647cf642f68d0f8259b43494c0/brick0/b0/.glusterfs/changeslogs/htime  /opt/backup_htime/brick0_b0

3. Run the following command to replace the OLD path in the htime file(s) with the new brick path, where OLD_BRICK_PATH is the brick path of the current volume, and NEW_BRICK_PATH is the brick path after snapshot restore.

   find <new_brick_htime_path> - name 'HTIME.*' -print0  | \
   xargs -0 sed -ci 's|<OLD_BRICK_PATH>|<NEW_BRICK_PATH>|g'

   For example:

   find /var/run/gluster/snaps/a4e2c4647cf642f68d0f8259b43494c0/brick0/b0/.glusterfs/changelogs/htime/ -name 'HTIME.*' -print0  | \
   xargs -0 sed -ci 's|/bricks/brick0/b0/|/var/run/gluster/snaps/a4e2c4647cf642f68d0f8259b43494c0/brick0/b0/|g'

4. Start the Master and Slave volumes and Geo-replication session on the restored volume. The status should update to Active.

BZ#1240333

Concurrent rename and lookup operations on a directory can cause both old and new directories to be "healed." Both directories will exist at the end of the operation and will have the same GFID. Clients might be unable to access some of the contents of the directory. Contact Red Hat Support for assistance with this issue.

Issues related to Self-heal

BZ#1063830

Performing add-brick or remove-brick operations on a volume having replica pairs when there are pending self-heals can cause potential data loss.

Workaround: Ensure that all bricks of the volume are online and there are no pending self-heals. You can view the pending heal info using the command gluster volume heal volname info.

BZ#1230092

When you create a replica 3 volume, client quorum is enabled and set to auto by default. However, it does not get displayed in gluster volume info.

BZ#1233608

When cluster.data-self-heal, cluster.metadata-self-heal and cluster.entry-self-heal are set to off (through volume set commands), the Gluster CLI to resolve split-brain fails with File not in split brain message (even though the file is in split brain).

BZ#1240658

When files are accidentally deleted from a brick in a replica pair in the back-end, and gluster volume heal VOLNAME full is run, then there is a chance that the files may not get healed.

Workaround: Perform a lookup on the files from the client (mount). This triggers the heal.

BZ#1173519

If you write to an existing file and go over the _AVAILABLE_BRICK_SPACE_, the write fails with an I/O error.

Workaround: Use the cluster.min-free-disk option. If you routinely write files up to nGB in size, then you can set min-free-disk to an mGB value greater than n.

For example, if your file size is 5GB, which is at the high end of the file size you will be writing, you might consider setting min-free-disk to 8 GB. This ensures that the file will be written to a brick with enough available space (assuming one exists).

# gluster v set _VOL_NAME_ min-free-disk 8GB

BZ#1021466

After setting Quota limit on a directory, creating sub directories and populating them with files and renaming the files subsequently while the I/O operation is in progress causes a quota limit violation.

BZ#1020713

In a distribute or distribute replicate volume, while setting quota limit on a directory, if one or more bricks or one or more replica sets respectively, experience downtime, quota is not enforced on those bricks or replica sets, when they are back online. As a result, the disk usage exceeds the quota limit.

Workaround: Set quota limit again after the brick is back online.

Issues related to NFS-Ganesha

BZ#1259402

When vdsmd and abrt are installed alongside each other, vdsmd overwrites abrt core dump configuration in /proc/sys/kernel/core_pattern. This prevents NFS-Ganesha from generating core dumps.

Workaround: Disable core dumps in /etc/vdsm/vdsm.conf by setting core_dump_enable to false, and then restart the abrt-ccpp service:

# systemctl restart abrt-ccpp

BZ#1257548

nfs-ganesha service monitor script which triggers IP failover runs periodically every 10 seconds. The ping-timeout of the glusterFS server (after which the locks of the unreachable client gets flushed) is 42 seconds by default. After an IP failover, some locks may not get cleaned by the glusterFS server process, hence reclaiming the lock state by NFS clients may fail.

Workaround: It is recommended to set the nfs-ganesha service monitor period interval (default 10sec) at least as twice as the Gluster server ping-timout (default 42sec).

Hence, either you must decrease the network ping-timeout using the following command:

# gluster volume set <volname> network.ping-timeout <ping_timeout_value>

or increase nfs-service monitor interval time using the following commands:

# pcs resource op remove nfs-mon monitor

# pcs resource op add nfs-mon monitor interval=<interval_period_value> timeout=<timeout_value>

BZ#1224250

Same epoch values on all the NFS-Ganesha heads results in NFS server sending NFS4ERR_FHEXPIRED error instead of NFS4ERR_STALE_CLIENTID or NFS4ERR_STALE_STATEID after failover. This results in NFSv4 clients not able to recover locks after failover.

Workaround: To use NFSv4 locks, specify different epoch values for each NFS-Ganesha head before setting up the NFS-Ganesha cluster.

BZ#1226874

If NFS-Ganesha is started before you set up an HA cluster, there is no way to validate the cluster state and stop NFS-Ganesha if the set up fails. Even if the HA cluster set up fails, the NFS-Ganesha service continues running.

Workaround: If HA set up fails, run service nfs-ganesha stop on all nodes in the HA cluster.

BZ#1228196

If you have less than three nodes, pacemaker shuts down HA.

Workaround: To restore HA, add a third node with ganesha-ha.sh --add $path-to-config $node $virt-ip.

BZ#1233533

When the nfs-ganesha option is turned off, gluster NFS may not restart automatically.. The volume may no longer be exported from the storage nodes via a nfs-server.

Workaround:

1. Turn off the nfs.disable option for the volume:

   gluster volume set volume name nfs.disable off

2. Restart the volume:

   gluster volume start volume name force

BZ#1235597

On the nfs-ganesha server IP, showmount does not display a list of the clients mounting from that host.

BZ#1236017

When a server is rebooted, services such as pcsd and nfs-ganesha do not start by default. nfs-ganesha won't be running on the rebooted node, so it won't be part of the HA-cluster.

Workaround: Manually restart the services after a server reboot.

BZ#1240258

When files and directories are created on the mount point with root squash enabled for nfs-ganesha, executing ls command displays user:group as 4294967294:4294967294 instead of nfsnobody:nfsnobody. This is because the client maps only 16 bit unsigned representation of -2 to nfsnobody whereas 4294967294 is 32 bit equivalent of -2.

This is currently a limitation in upstream nfs-ganesha.

Issues related to Red Hat Gluster Storage Volumes

BZ#1306656

When management encryption is enabled, and a volume is started before glusterd has been started on all nodes in the cluster, the bricks on late-starting nodes are assigned different ports. This results in the bricks being inaccessible, as the new ports are blocked by the firewall.

Workaround: When management encryption is enabled, ensure glusterd is started on all nodes before starting volumes.

BZ#1311362

Red Hat Gluster Storage 3.1 Update 2 adds a new directory (brick_path/.glusterfs/indices/dirty) to assist with internal maintenance. Version 3.1 Update 2 incorrectly expects this directory to be present when running commands, even on nodes with older Red Hat Gluster Storage versions, resulting in misleading output.

When a node with Red Hat Gluster Storage 3.1 Update 2 is used to run the gluster volume heal volname command on older nodes, the output of a gluster volume heal info command run from the new node contains the following message, even though all entries were processed:

Failed to process entries completely

Workaround: If not all nodes in your cluster have been updated to Red Hat Gluster Storage 3.1 Update 2, you can perform either of the following actions to work around the issue.

• Use older nodes to review heal info output.
• For each brick, check that the only index entry listed under the brick_path/.glusterfs/indices/xattrop directory is xattrop-*.

BZ#1304585

When quota is disabled on a volume, a cleanup process is initiated to clean up the extended attributes used by quota. If this cleanup process is still in progress when quota is re-enabled, extended attributes for the newly enabled quota can be removed by the cleanup process. This has negative effects on quota accounting.

BZ#1306907

During an inode forget operation, files under the quarantine directory are removed. The inode forget operation is called during the unlinking of a file, and when the inode table's LRU (Least Recently Used) cache size exceeds 16 KB. This means that, when a corrupted file is not accessed for a long time, and the LRU cache exceeds 16 KB, the corrupted file will be removed from the quarantine directory. This results in the corrupted file not being shown in BitRot status output, even though the corrupted file has not been deleted from the volume itself.

BZ#986090

Currently, the Red Hat Gluster Storage server has issues with mixed usage of hostnames, IPs and FQDNs to refer to a peer. If a peer has been probed using its hostname but IPs are used during add-brick, the operation may fail. It is recommended to use the same address for all the operations, that is, during peer probe, volume creation, and adding/removing bricks. It is preferable if the address is correctly resolvable to a FQDN.

BZ#1260779

In a distribute-replicate volume, the getfattr -n replica.split-brain-status <path-to-dir> command on mount-point might report that the directory is not in split-brain even though it is.

Workaround: To know the split-brain status of a directory, run the following command:

# gluster v heal <volname> info split-brain

BZ#852293

The management daemon does not have a rollback mechanism to revert any action that may have succeeded on some nodes and failed on the those that do not have the brick's parent directory. For example, setting the volume-id extended attribute may fail on some nodes and succeed on others. Because of this, the subsequent attempts to recreate the volume using the same bricks may fail with the error brickname or a prefix of it is already part of a volume.

Workaround:

1. You can either remove the brick directories or remove the glusterfs-related extended attributes.
2. Try creating the volume again.

BZ#913364

An NFS server reboot does not reclaim the file LOCK held by a Red Hat Enterprise Linux 5.9 client.

BZ#1030438

On a volume, when read and write operations are in progress and simultaneously a rebalance operation is performed followed by a remove-brick operation on that volume, then the rm -rf command fails on a few files.

BZ#1224064

Glusterfind is a independent tool and is not integrated with glusterd. When a Gluster volume is deleted, respective glusterfind session directories/files for that volume persist.

Workaround: Manually, delete the Glusterfind session directory in each node for the Gluster volume in the /var/lib/glusterd/glusterfind directory.

BZ#1224153

When a brick process dies, BitD tries to read from the socket used to communicate with the corresponding brick. If it fails, BitD logs the failure to the log file. This results in many messages in the log files, leading to the failure of reading from the socket and an increase in the size of the log file.

BZ#1224162

Due to an unhandled race in the RPC interaction layer, brick down notifications may result in corrupted data structures being accessed. This can lead to NULL pointer access and segfault.

Workaround: When the Bitrot daemon (bitd) crashes (segfault), you can use volume start VOLNAME force to restart bitd on the node(s) where it crashed.

BZ#1224880

If you delete a gluster volume before deleting the Glusterfind session, then the Glusterfind session can't be deleted. A new session can't be created with same name.

Workaround: In all the nodes that were part of the volume before you deleted it, manually clean up the session directory, for example, /var/lib/glusterd/glusterfind/SESSION/VOLNAME.

BZ#1227672

A successful scrub of the filesystem (objects) is required to see if a given object is clean or corrupted. When a file gets corrupted and a scrub has not been run on the filesystem, there is a good chance of replicating corrupted objects in cases when the brick holding the good copy was offline when I/O was performed.

Workaround: Objects need to be checked on demand for corruption during healing.

BZ#1231150

When you set diagnostic.client-log-level DEBUG, and then reset the diagnostic.client-log-level option, DEBUG logs continue to appear in log files. INFO log level is enabled by default.

Workaround: Restart the volume using gluster volume start VOLNAME force, to reset log level defaults.

BZ#1233213

If you run a gluster volume info --xml command on a newly probed peer without running any other gluster volume command in between, brick UUIDs will appear as null ('00000000-0000-0000-0000-000000000000').

Workaround: Run any volume command (excluding gluster volume list and gluster volume get) before you run the info command. Brick UUIDs will then correctly populate.

BZ#1241314

The volume get VOLNAME enable-shared-storage option always shows as disabled, even when it is enabled.

Workaround: gluster volume info VOLNAME command shows the correct status of the enable-shared-storage option.

BZ#1297442

Currently, attempting to run the gluster volume get volname user.option command fails because the volume get command does not display user option values in its output.

Workaround: Run the gluster volume info volname command on the same volume to see the value of any user options.

BZ#1241336

When an Red Hat Gluster Storage node is shut down due to power failure or hardware failure, or when the network interface on a node goes down abruptly, subsequent gluster commands may time out. This happens because the corresponding TCP connection remains in the ESTABLISHED state. You can confirm this by executing the following command: ss -tap state established '( dport = :24007 )' dst IP-addr-of-powered-off-RHGS-node

Workaround: Restart glusterd service on all other nodes.

BZ#1223306

gluster volume heal VOLNAME info shows stale entries, even after the file is deleted. This happens due to a rare case when the gfid-handle of the file is not deleted.

Workaround: On the bricks where the stale entries are present, for example, <gfid:5848899c-b6da-41d0-95f4-64ac85c87d3f>, check if the file's gfid handle is not deleted by running the following command and checking whether the file appears in the output, for example, <brick-path>/.glusterfs/58/48/5848899c-b6da-41d0-95f4-64ac85c87d3f.

# find <brick-path>/.glusterfs -type f -links 1

If the file appears in the output of this command, delete the file using the following command.

# rm <brick-path>/.glusterfs/58/48/5848899c-b6da-41d0-95f4-64ac85c87d3f

BZ#1224180

In some cases, operations on the mount displays error: Input/Output error instead of Disk quota exceeded message after the quota limit is exceeded.

BZ#1244759

Sometimes gluster volume heal VOLNAME info shows some symlinks which need to be healed for hours.

To confirm this issue, the files must have the following extended attributes:

# getfattr -d -m. -e hex -h /path/to/file/on/brick | grep trusted.ec

Example output: 
trusted.ec.dirty=0x3000
trusted.ec.size=0x3000
trusted.ec.version=0x30000000000000000000000000000001

The first four digits must be 3000 and the file must be a symlink/softlink.

Workaround: Execute the following commands on the files in each brick and ensure to stop all operations on them.

1. Delete trusted.ec.size.

   # setfattr -x trusted.ec.size /path/to/file/on/brick

2. First 16 digits must have '0' in both trusted.ec.dirty and trusted.ec.version attributes and the rest of the 16 digits should remain as is. If the number of digits is less than 32, then use '0' s as padding.

   # setfattr -n trusted.ec.dirty -v 0x00000000000000000000000000000000 /path/to/file/on/brick
   # setfattr -n trusted.ec.version -v 0x00000000000000000000000000000001 /path/to/file/on/brick

Issues related to Red Hat Gluster Storage Server

BZ#1306667

If server-side quorum is enabled, and the quorum conditions are not met, starting a volume should fail. Currently, executing gluster volume start incorrectly succeeds even when quorum conditions are not met. However, because stopping the volume is correctly dependent on quorum conditions being met, this means that attempts to stop the volume fail while quorum is enabled.

Workaround:

1. Disable server-side quorum:

   # gluster volume reset volname cluster.server-quorum-type

2. Stop the volume.
3. Re-enable server-side quorum.

   # gluster volume set volname cluster.server-quorum-type server

BZ#1298955

When Red Hat Gluster Storage is set up with a server version of 3.1 Update 1 and a client version of 3.0 Update 4, attempting to set any option with the volume set command fails with the following error:

volume set: failed: One or more connected clients cannot support the feature being set. These clients need to be upgraded or disconnected before running this command again

When operating correctly, this restriction is in place to prevent newer features from being enabled on a volume when the clients in use cannot support the feature. Currently, the restriction check is incorrect, and will prevent even valid, supported options from being set.

Workaround: Upgrade all clients to the same version of Red Hat Gluster Storage as the server.

BZ#1266824

After an ISO installation, the ntpd service does not start by default on Red Hat Enterprise Linux 7. The server is out of sync with the rest of the cluster. This is visible if there is a huge difference between the current date and the system time.

Workaround: You must configure the ntpd service manually after installation. Execute the following commands to enable and start the ntpd service:

# systemctl enable ntpd

# systemctl start ntpd

Issues related to Samba

BZ#1300572

Due to a bug in the Linux CIFS client, SMB2.0+ connections from Linux to Red Hat Gluster Storage currently will not work properly. SMB1 connections from Linux to Red Hat Gluster Storage, and all connections with supported protocols from Windows continue to work.

Workaround: If practical, restrict Linux CIFS mounts to SMB version 1. The simplest way to do this is to not specify the vers mount option, since the default setting is to use only SMB version 1. If restricting Linux CIFS mounts to SMB1 is not practical, disable asynchronous I/O in Samba by setting aio read size to 0 in the smb.conf file. Disabling asynchronous I/O is not generally recommended and may negatively impact performance on other clients.

BZ#1282452

Attempting to upgrade to ctdb version 4 fails when ctdb2.5-debuginfo is installed, because the ctdb2.5-debuginfo package currently conflicts with the samba-debuginfo package.

Workaround: Manually remove the ctdb2.5-debuginfo package before upgrading to ctdb version 4. If necessary, install samba-debuginfo after the upgrade.

BZ#1164778

Any changes performed by an administrator in a Gluster volume's share section of smb.conf are replaced with the default Gluster hook scripts settings when the volume is restarted.

Workaround: The administrator must perform the changes again on all nodes after the volume restarts.

Issues related to SELinux

BZ#1294762

When the Red Hat Gluster Storage Container is deployed on Red Hat Enterprise Atomic Host, SELinux policy labels the /var/log/glusterfs directory as svirt_sandbox_file_t. Logrotate cannot run on files with this label, and logs AVC denials when log rotation is attempted on files in /var/log/glusterfs. This means that Red Hat Gluster Storage logs cannot currently be rotated, and could potentially fill up and consume a large amount of storage as a result. Correcting this requires updates to the selinux-policy package. In the meantime, you can work around this issue by resetting the label of /var/log/glusterfs after the host volume is bind mounted inside the container.

Workaround:

1. Start the container and bind mount the host volume:

   # docker run ... -v /var/log/glusterfs:/var/log/glusterfs:z ... image_name
   # docker exec -it container_id /bin/bash

2. In the container, run the following command to manually apply the appropriate SELinux label.

   # chcon -Rt glusterd_log_t /var/log/glusterfs

Note that this workaround cannot persist to subsequent docker runs, and must be performed for each docker run.

BZ#1256635

Red Hat Gluster Storage does not currently support SELinux Labeled mounts.

On a FUSE mount, SELinux cannot currently distinguish file systems by subtype, and therefore cannot distinguish between different FUSE file systems (BZ#1291606). This means that a client-specific policy for Red Hat Gluster Storage cannot be defined, and SELinux cannot safely translate client-side extended attributes for files tracked by Red Hat Gluster Storage.

A workaround is in progress for NFS-Ganesha mounts as part of BZ#1269584. When complete, BZ#1269584 will enable Red Hat Gluster Storage support for NFS version 4.2, including SELinux Labeled support.

BZ#1290514 , BZ#1292781

Current SELinux policy prevents the use of the ctdb enablescript and ctdb disablescript commands.

Workaround: Instead of running ctdb disablescript script, run chmod -x /etc/ctdb/events.d/script as the root user. Instead of running ctdb enablescript script, run chmod +x /etc/ctdb/events.d/script as the root user.

BZ#1291194 , BZ#1292783

Current SELinux policy prevents ctdb's 49.winbind event script from executing smbcontrol. This can create inconsistent state in winbind, because when a public IP address is moved away from a node, winbind fails to drop connections made through that IP address.

General issues

BZ#1303125

The defrag variable is not being reinitialized during glusterd restart. This means that if glusterd fails while the following processes are running, it does not reconnect to these processes after restarting:

• rebalance
• tier
• remove-brick

This results in these processes continuing to run without communicating with glusterd. Additionally, glusterd does not retain the decommission_is_in_progress flag that is set to indicate that the rebalance process is running.

If glusterd fails and restarts on a node where remove-brick was triggered and the rebalance process is not yet complete, but the rebalance process on other nodes has already completed, then the remove-brick commit operation succeeds because glusterd cannot identify that there is an ongoing rebalance operation on the node. This can result in data loss.

Workaround:

• Stop or kill the rebalance process before restarting glusterd. This ensures that a new rebalance process is spawned when glusterd restarts.
• On the node on which glusterd restarted, check the status of the remove-brick process. Only execute the remove-brick commit command when remove-brick status shows that data migration is complete.

BZ#1290653

When the gluster volume status all tasks command is executed, messages like the following are recorded in the glusterd log.

Failed to aggregate response from  node/brick

This error is logged erroneously, and can be safely ignored.

GFID mismatches cause errors

If files and directories have different GFIDs on different back-ends, the glusterFS client may hang or display errors. Contact Red Hat Support for more information on this issue.

BZ#1260119

glusterfind command must be executed from one node of the cluster. If all the nodes of cluster are not added in known_hosts list of the command initiated node, then glusterfind create command hangs.

Workaround: Add all the hosts in peer including local node to known_hosts.

BZ#1030962

On installing the Red Hat Gluster Storage Server from an ISO or PXE, the kexec-tools package for the kdump service gets installed by default. However, the crashkernel=auto kernel parameter required for reserving memory for the kdump kernel, is not set for the current kernel entry in the bootloader configuration file, /boot/grub/grub.conf. Therefore the kdump service fails to start up with the following message available in the logs.

kdump: No crashkernel parameter specified for running kernel

On installing a new kernel after installing the Red Hat Gluster Storage Server, the crashkernel=auto kernel parameter is successfully set in the bootloader configuration file for the newly added kernel.

Workaround: After installing the Red Hat Gluster Storage Server, the crashkernel=auto, or an appropriate crashkernel=sizeM kernel parameter can be set manually for the current kernel in the bootloader configuration file. After that, the Red Hat Gluster Storage Server system must be rebooted, upon which the memory for the kdump kernel is reserved and the kdump service starts successfully. Refer to the following link for more information on Configuring kdump on the Command Line

BZ#1058032

While migrating VMs, libvirt changes the ownership of the guest image, unless it detects that the image is on a shared filesystem and the VMs can not access the disk images as the required ownership is not available.

Workaround: Before migration, power off the VMs. When migration is complete, restore the ownership of the VM Disk Image (107:107) and start the VMs.

Concurrent volume and peer management

The glusterd service crashes when volume management commands are executed concurrently with peer commands.

BZ#1130270

If a 32 bit Samba package is installed before installing Red Hat Gluster Storage Samba package, the installation fails as Samba packages built for Red Hat Gluster Storage do not have 32 bit variants.

Workaround: Uninstall 32 bit variants of Samba packages.

BZ#1139183

The Red Hat Gluster Storage 3.0 version does not prevent clients with older versions from mounting a volume on which rebalance is performed. Users with versions older than Red Hat Gluster Storage 3.0 mounting a volume on which rebalance is performed can lead to data loss.

Workaround: You must install latest client version to avoid this issue.

BZ#1127178

If a replica brick goes down and comes up when rm -rf command is executed, the operation may fail with the message Directory not empty.

Workaround: Retry the operation when there are no pending self-heals.

BZ#969020

Renaming a file during remove-brick operation may cause the file not to get migrated from the removed brick.

Workaround: Check the removed brick for any files that might not have been migrated and copy those to the gluster volume before decommissioning the brick.

BZ#1007773

When remove-brick start command is executed, even though the graph change is propagated to the NFS server, the directory inodes in memory are not refreshed to exclude the removed brick. Hence, new files that are created may end up on the removed-brick.

Workaround: If files are found on the removed-brick path after remove-brick commit, copy them via a gluster mount point before re-purposing the removed brick.

BZ#1120437

Executing peer-status command on probed host displays the IP address of the node on which the peer probe was performed. For example, when probing node B with a hostname from node A, executing peer status command on node B displays IP address of node A instead of its hostname.

Workaround: Probe node A from node B with hostname of node A. For example, execute the command: # gluster peer probe HostnameA from node B.

BZ#1122371

The NFS server process and gluster self-heal daemon process restarts when gluster daemon process is restarted.

BZ#1110692

Executing remove-brick status command, after stopping remove-brick process, fails and displays a message that the remove-brick process is not started.

BZ#1123733

Executing a command which involves glusterd-glusterd communication gluster volume status immediately after one of the nodes is down hangs and fails after 2 minutes with cli-timeout message. The subsequent command fails with the error message Another transaction in progress for 10 mins (frame timeout).

Workaround: Set a non-zero value for ping-timeout in /etc/glusterfs/glusterd.vol file.

BZ#1136718

The AFR self-heal can leave behind a partially healed file if the brick containing AFR self-heal source file goes down in the middle of heal operation. If this partially healed file is migrated before the brick that was down comes online again, the migrated file would have incorrect data and the original file would be deleted.

BZ#1139193

After add-brick operation, any application (like git) which attempts opendir on a previously present directory fails with ESTALE/ENOENT errors.

BZ#1141172

If you rename a file from multiple mount points, there are chances of losing the file. This issue is witnessed since mv command sends unlinks instead of renames when source and destination happens to be hard links to each other. Hence, the issue is in mv, distributed as part of coreutils in various Linux distributions.

For example, if there are parallel renames of the form (mv a b) and (mv b a) where a and b are hard links to the same file, because of the above mentioned behavior of mv, unlink (a) and unlink (b) would be issued from both instances of mv. This results in losing both the links a and b and hence the file.

BZ#979926

When any process establishes a TCP connection with glusterfs servers of a volume using port > 1023, the server rejects the requests and the corresponding file or management operations fail. By default, glusterfs servers treat ports > 1023 as unprivileged.

Workaround: To disable this behavior, enable rpc-auth-allow-insecure option on the volume using the steps given below:

1. To allow insecure connections to a volume, run the following command:

   # gluster volume set VOLNAME rpc-auth-allow-insecure on

2. To allow insecure connections to glusterd process, add the following line in /etc/glusterfs/glusterd.vol file:

   option rpc-auth-allow-insecure on

3. Restart glusterd process using the following command:

   # service glusterd restart

4. Restrict connections to trusted clients using the following command:

   # gluster volume set VOLNAME auth.allow IP address

BZ#1139676

Renaming a directory may cause both source and target directories to exist on the volume with the same GFID and make some files in these directories not visible from the mount point. The files will still be present on the bricks.

Workaround: The steps to fix this issue are documented in: https://access.redhat.com/solutions/1211133

BZ#1139676

Renaming a directory may cause both source and target directories to exist on the volume with the same GFID and make some files in these directories not visible from the mount point. The files will still be present on the bricks.

Workaround: The steps to fix this issue are documented in: https://access.redhat.com/solutions/1211133

BZ#1030309

During directory creations attempted by geo-replication, though an mkdir fails with EEXIST, the directory might not have a complete layout for sometime and the directory creation fails with Directory exists message. This can happen if there is a parallel mkdir attempt on the same name. Till the other mkdir completes, layout is not set on the directory. Without a layout, entry creations within that directory fails.

Workaround: Set the layout on those sub-volumes where the directory is already created by the parallel mkdir before failing the current mkdir with EEXIST.

Note

This is not a complete fix as the other mkdir might not have created directories on all sub-volumes. The layout is set on the sub-volumes where directory is already created. Any file or directory names which hash to these sub-volumes on which layout is set, can be created successfully.

BZ#1238067

In rare instances, glusterd may crash when it is stopped. The crash is due to a race between the clean up thread and the running thread and doesn't impact functionality. The clean up thread releases URCU resources while a running thread continues to try to access it, which results in a crash.

Issues related to Red Hat Gluster Storage AMI

BZ#1267209

The redhat-storage-server package is not installed by default in a Red Hat Gluster Storage Server 3 on Red Hat Enterprise Linux 7 AMI image.

Workaround: It is highly recommended to manually install this package using yum.

# yum install redhat-storage-server

The redhat-storage-server package primarily provides the /etc/redhat-storage-release file, and sets the environment for the storage node.

Issues related to Upgrade

BZ#1247515

As part of the tiering feature, a new dictionary key value pair was introduced to send the number of bricks in the hot-tier. So glusterd expects this key in a dictionary which is sent to other peers during the data exchange. Since one of the node runs Red Hat Gluster Storage 2.1, this key value pair is not sent which causes glusterd running on Red Hat Gluster Storage 3.1 to complain about the missing key value pair from the peer data.

Workaround: No functionality issues. An error is displayed in glusterd logs.

BZ#1303566

When a user selects the auto-start option in the Create Geo-replication Session user interface, the use_meta_volume option is not set. This means that the geo-replication session is started without a metadata volume, which is not a recommended configuration.

Workaround: After session start, go to the geo-replication options tab for the master volume and set the use_meta_volume option to true.

BZ#1246047

If a logical network is attached to the interface with boot protocol DHCP, the IP address is not assigned to the interface on saving network configuration, if DHCP server responses are slow.

Workaround: Click Refresh Capabilities on the Hosts tab and the network details are refreshed and the IP address is correctly assigned to the interface.

BZ#1164662

The Trends tab in the Red Hat Gluster Storage Console appears to be empty after the ovirt engine restarts. This is due to the Red Hat Gluster Storage Console UI-plugin failing to load on the first instance of restarting the ovirt engine.

Workaround: Refresh (F5) the browser page to load the Trends tab.

BZ#1167305

The Trends tab on the Red Hat Gluster Storage Console does not display the thin-pool utilization graphs in addition to the brick utilization graphs. Currently, there is no mechanism for the UI plugin to detect if the volume is provisioned using the thin provisioning feature.

BZ#1167572

On editing the cluster version in the Edit Cluster dialog box on the Red Hat Gluster Storage Console, the compatible version field gets loaded with the highest available compatibility version by default, instead of the current version of the cluster.

Workaround: Select the correct version of the cluster in the Edit Cluster dialog box before clicking on the OK button.

BZ#990108

Resetting the user.cifs option using the Create Volume operation on the Volume Options tab on the Red Hat Gluster Storage Console reports a failure.

BZ#1054366

In Internet Explorer 10, while creating a new cluster with Compatibility version 3.3, the Host drop down list does not open correctly. Also, if there is only one item, the drop down list gets hidden when the user clicks on it.

BZ#1053395

In Internet Explorer, while performing a task, an error message Unable to evaluate payload is displayed.

BZ#1056372

When no migration is occurring, incorrect error message is displayed for the stop migrate operation.

BZ#1048426

When there are more entries in rebalance status and remove-brick status window, the column names scrolls up along with the entries while scrolling the window.

Workaround: Scroll up the rebalance status and remove-brick status window to view the column names.

BZ#1053112

When large sized files are migrated, the stop migrate task does not stop the migration immediately but only after the migration is complete.

BZ#1040310

If the Rebalance Status dialog box is open in the Red Hat Gluster Storage Console while Rebalance is being stopped from the Command Line Interface, the status is currently updated as Stopped. But if the Rebalance Status dialog box is not open, the task status is displayed as Unknown because the status update relies on the gluster Command Line Interface.

BZ#838329

When incorrect create request is sent through REST api, an error message is displayed which contains the internal package structure.

BZ#1049863

When Rebalance is running on multiple volumes, viewing the brick advanced details fails and the error message Could not fetch brick details, please try again later is displayed in the Brick Advanced Details dialog box.

BZ#1024184

If there is an error while adding bricks, all the "." characters of FQDN / IP address in the error message will be replaced with "_" characters.

BZ#975399

When Gluster daemon service is restarted, the host status does not change to UP from Non-Operational immediately in the Red Hat Gluster Storage Console. There would be a 5 minute interval for auto-recovery operations which detect changes in Non-Operational hosts.

BZ#971676

While enabling or disabling Gluster hooks, the error message displayed if all the servers are not in UP state is incorrect.

BZ#1057122

While configuring the Red Hat Gluster Storage Console to use a remote database server, on providing either yes or no as input for Database host name validation parameter, it is considered as No.

BZ#1042808

When remove-brick operation fails on a volume, the Red Hat Gluster Storage node does not allow any other operation on that volume.

Workaround: Perform commit or stop for the failed remove-brick task, before another task can be started on the volume.

BZ#1060991

In Red Hat Gluster Storage Console, Technology Preview warning is not displayed for stop remove-brick operation.

BZ#1057450

Brick operations like adding and removing a brick from Red Hat Gluster Storage Console fails when Red Hat Gluster Storage nodes in the cluster have multiple FQDNs (Fully Qualified Domain Names).

Workaround: Host with multiple interfaces should map to the same FQDN for both Red Hat Gluster Storage Console and gluster peer probe.

BZ#1038663

Framework restricts displaying delete actions for collections in RSDL display.

BZ#1061677

When Red Hat Gluster Storage Console detects a remove-brick operation which is started from Gluster Command Line Interface, engine does not acquire lock on the volume and Rebalance task is allowed.

Workaround: Perform commit or stop on remove-brick operation before starting Rebalance.

BZ#1046055

While creating volume, if the bricks are added in root partition, the error message displayed does not contain the information that Allow bricks in root partition and re-use the bricks by clearing xattrs option needs to be selected to add bricks in root partition.

Workaround: Select Allow bricks in root partition and re-use the bricks by clearing xattrs option to add bricks in root partition.

BZ#1060991

In Red Hat Gluster Storage Console UI, Technology Preview warning is not displayed for stop remove-brick operation.

BZ#1066130

Simultaneous start of Rebalance on volumes that span same set of hosts fails as gluster daemon lock is acquired on participating hosts.

Workaround: Start Rebalance again on the other volume after the process starts on first volume.

BZ#1200248

The Trends tab on the Red Hat Gluster Storage Console does not display all the network interfaces available on a host. This limitation is because the Red Hat Gluster Storage Console ui-plugin does not have this information.

Workaround:The graphs associated with the hosts are available in the Nagios UI on the Red Hat Gluster Storage Console. You can view the graphs by clicking the Nagios home link.

BZ#1224724

The Volume tab loads before the dashboard plug-in is loaded. When the dashboard is set as the default tab, the volume sub-tab remains on top of dashboard tab.

Workaround: Switch to a different tab and the sub-tab is removed.

BZ#1225826

In Firefox-38.0-4.el6_6, check boxes and labels in Add brick and Remove Brick dialog boxes are misaligned.

BZ#1228179

gluster volume set help-xml does not list the config.transport option in the UI.

Workaround: Type the option name instead of selecting it from the drop-down list. Enter the desired value in the value field.

BZ#1231723

Storage devices with disk labels appear as locked on the storage devices sub-tab. When a user deletes a brick by removing lv, vg, pv and partition, the storage device appears with the lock symbol and the user is unable to create a new brick from the storage device.

Workaround: Using the CLI, manually create a partition. Click Sync on the Storage Device sub-tab under the host shows the created partition in the UI. The partition appears as a free device that can be used to create a brick through the Red Hat Gluster Storage Console GUI.

BZ#1231725

Red Hat Gluster Storage Console cannot detect bricks that are created manually using the CLI and mounted to a location other than /rhgs. Users must manually type the brick directory in the Add Bricks dialog box.

Workaround: Mount bricks in the /rhgs folder, which are detected automatically by Red Hat Gluster Storage Console.

BZ#1232275

Blivet provides only partial device details on any major disk failure. The Storage Devices tab does not show some storage devices if the partition table is corrupted.

Workaround: Clean the corrupted partition table using the dd command. All storage devices are then synced to the UI.

BZ#1233592

The Force Remove checkbox appears in the Remove GeoReplication window even if it is unnecessary. Even if you use the force option, it is the equivalent of using w/o force as the option is not available in the Gluster CLI to remove a geo-replication session.

BZ#1232575

When performing a search on a specific cluster, the volumes of all clusters that have a name beginning with the selected cluster name are returned.

BZ#1234445

The task-id corresponding to the previously performed retain/stop remove-brick is preserved by engine. When a user queries for remove-brick status, it passes the bricks of both the previous remove-brick as well as the current bricks to the status command. The UI returns the error Could not fetch remove brick status of volume.

In Gluster, once a remove-brick has been stopped, the status can't be obtained.

BZ#1235559

The same audit log messages is used in two cases:

1. When the current_scheduler value is set as oVirt in Gluster.
2. When the current_scheduler value is set as oVirt in Gluster.

The first message should be corrected to mention that the flag is set successfully to oVirt in the CLI.

BZ#1236410

While syncing snapshots created from the CLI, the engine populates the creation time, which is returned from the Gluster CLI. When you create a snapshot from the UI, the engine current time is marked as the creation time in the engine DB. This leads to a mismatch between creation times for snapshots created from the engine and the CLI.

BZ#1238244

Upgrade is supported from Red Hat Gluster Storage 3.0 to 3.1, but you cannot upgrade from Red Hat Gluster Storage 2.1 to 3.1.

Workaround: Reinstall Red Hat Gluster Storage 3.1 on existing deployments of 2.1 and import existing clusters. Refer to the Red Hat Guster Storage Console Installation Guide for further information.

BZ#1238332

When the console doesn't know that glusterd is not running on the host, removal of a brick results in an undetermined state (question mark). When glusterd is started again, the brick remains in an undetermined state. The volume command shows status as not started but the remove-brick status command returns null in the status field.

Workaround: Stop/commit remove-brick from the CLI.

BZ#1238540

When you create volume snapshots, time zone and time stamp details are appended to the snapshot name. The engine passes only the prefix for the snapshot name. If master and slave clusters of a geo-replication session are in different time zones (or sometimes even in the same time zone), the snapshot names of the master and slave are different. This causes a restore of a snapshot of the master volume to fail because the slave volume name does not match.

Workaround: Identify the respective snapshots for the master and slave volumes and restore them separately from the gluster CLI by pausing the geo-replication session.

BZ#1240627

There is a time out for a VDSM call from the oVirt engine. Removing 256 snapshots from a volume causes the engine to time out during the call. UI shows a network error as the command timed out. However, the snapshots were deleted successfully.

Workaround: Delete the snapshots in smaller chunks using the Delete option, which supports the deletion of multiple snapshots at once.

BZ#1242128

Deleting a gluster volume does not remove the /etc/fstab entries for the bricks. A Red Hat Enterprise Linux 7 system may fail to boot if the mount fails for any entry in the /etc/fstab file. If the LVs corresponding to the bricks are deleted but not the respective entry in /etc/fstab, then the system may not boot.

Workaround:

1. Ensure that /etc/fstab entries are removed when the Logical Volumes are deleted from system.
2. If the system fails to boot, start it in emergency mode, use your root password, remount '/' in rw, edit fstab, save, and then reboot.

BZ#1243443

Unable to resolve Gluster hook conflicts when there are three conflicts: Content + Status + Missing

Workaround: Resolve the Content + Missing hook conflict before resolving the Status conflict.

BZ#1243537

Labels do not show enough information for the Graphs shown on the Trends tab. When you select a host in the system tree and switch to the Trends tab, you will see two graphs for the mount point '/': one graph for the total space used and another for the inodes used on the disk.

Workaround:

1. The graph with y axis legend as %(Total: ** GiB/Tib) is the graph for total space used.
2. The graph with y axis legend as %(Total: number) is the graph for inode usage.

BZ#1244507

If the meta volume is not already mounted, snapshot schedule creation fails as it needs meta volume to be mounted so that CLI based scheduling can be disabled.

Workaround: If meta volume is available, mount it from the CLI, and then create the snapshot schedule in the UI.

BZ#1246038

Selection of the Gluster network role is not persistent when changing multiple fields. If you attach this logical network to an interface, it is ignored when you add bricks.

Workaround: Reconfigure the role for the logical network.

BZ#1134319

When run on versions higher than Firefox 17, the Red Hat Storage Console login page displays a browser incompatibility warning.

BZ#1293412

When self-heal is required after an inode refresh, the file operation that triggered the heal process is served after the heal completes. This means that large files, such as virtual machine images, become unresponsive until the heal is complete and the file operation returns.

Workaround: Disable client-side self-heal to prevent file operations from blocking file access. Pending heals will still be tracked by the self-heal daemon.

# gluster volume set volname cluster.data-self-heal off

All images in data center displayed regardless of context

In the case that the Red Hat Gluster Storage server nodes and the Red Hat Enterprise Virtualization Hypervisors are present in the same data center, the servers of both types are listed for selection when you create a virtual machine or add a storage domain. Red Hat recommends that you create a separate data center for the Red Hat Gluster Storage server nodes.

BZ#1004745

If a replica pair is down while taking a snapshot of a Nova instance on top of a Cinder volume hosted on a Red Hat Gluster Storage volume, the snapshot process may not complete as expected.

BZ#980977, BZ#1017340

If storage becomes unavailable, the volume actions fail with error_deleting message.

Workaround: Run gluster volume delete VOLNAME force to forcefully delete the volume.

BZ#1062848

When a nova instance is rebooted while rebalance is in progress on the Red Hat Gluster Storage volume, the root file system will be mounted as read-only after the instance comes back up. Corruption messages are also seen on the instance.