Chapter 3. New features

Setting ownership is faster when using switch-from-non-containerized-to-containerized-ceph-daemons.yml

Previously, the chown command in the switch-from-non-containerized-to-containerized-ceph-daemons.yml playbook unconditionally re-applied the ownership of Ceph directories and files causing a lot of write operations. With this update, the command has been improved to run faster. This is especially useful on a Red Hat Ceph Storage cluster with a significant amount of directories and files in the /var/lib/ceph/ directory.

The new device_class Ansible configuration option

With the device_class`feature, you can alleviate post deployment configuration by updating the `groups_vars/osd.yml file in the desired layout. This feature offers you multi-backend support by avoiding to comment out sections after deploying Red Hat Ceph Storage.

Removing iSCSI targets using Ansible

Previously, the iSCSI targets had to be removed manually before purging the storage cluster. Starting with this release, the ceph-ansible playbooks remove the iSCSI targets as expected.

osd_auto_discovery now works with the batch subcommand

Previously, when osd_auto_discovery was activated, the batch subcommand did not create OSDs as expected. With this update, when batch is used with osd_auto_discovery, all the devices found by the ceph-ansible utility become OSDs and are passed in batch as expected.

The Ceph Ansible playbooks are compatible with Ansible 2.7

Starting with this release, users can install Ansible 2.7 and run the latest ceph-ansible playbooks for {storage-product}.

New options to use pre-downloaded container images

Previously, it was not possible to install Red Hat Ceph Storage Dashboard and the Prometheus plug-in without access to the Red Hat Container Registry. This update adds the following Ansible options that allow you to use pre-downloaded container images:

The RESTful plug-in now exposes performance counters

Th RESTful plug-in for the Ceph Manager (ceph-mgr) now exposes performance counters that include a number of Ceph Object Gateway metrics. To query the performance counters through the REST API provided by the RESTful plug-in, access the /perf endpoint.

New ceph-volume subcommand: inventory

The ceph-volume utility now supports a new inventory subcommand. The subcommand describes every device in the system, reports if it is available or not and if it is used by the ceph-disk utility.

The ceph-volume tool can now set the sizing of journals and block.db

Previously, sizing for journals and block.db volumes could only be set in the ceph.conf file. With this update, the ceph-volume tool can set the sizing of journals and block.db. This exposes sizing right on the command line interface (CLI) so the user can use tools like ceph-ansible or the CLI directly to set or change sizing when creating an OSD.

New ceph-volume lvm zap options: --osd.id and --osd-fsid

The ceph-volume lvm zap command now supports the --osd.id and --osd-fsid options. Use these options to remove any devices for an OSD by providing its ID or FSID, respectively. This is especially useful if you are not aware of the actual device names or logical volumes in use by that OSD.

Renaming users is now supported

This update of Red Hat Ceph Storage adds the ability to rename the Ceph Object Gateway users. For details, see the Rename a User section in the Object Gateway Guide for Red Hat Enterprise Linux or for Ubuntu.

The Ceph Object Gateway now supports the use of SSE-S3 headers

Clients and applications can successfully negotiate SSE-S3 encryption using the global, default encryption key, if one has been configured. Previously, the default key only used SSE-KMS encryption.

The x-amz-version-id header is now supported

The x-amz-version-id header is now returned by PUT operations on versioned buckets to conform to the S3 protocol. With this enhancement, clients now know the version ID of the objects they create.

New commands to view the RADOS objects and orphans

This release adds two new commands to view how Object Gateway maps to RADOS objects and produce a potential list of orphans for further processing. The radosgw-admin bucket radoslist --bucket=<bucket_name> command lists all RADOS objects in the bucket. The rgw-orphan-list command lists all orphans in a specified pool. These commands keep intermediate results on the local file system.

Ability to associate one email address to multiple user accounts

This update adds the ability to create multiple Ceph Object Gateway (RGW) user accounts with the same email address.

Ability to search for users by access-key

This update adds the ability to search for users by the access-key as a search string when using the radosgw-admin utility:

Keystone S3 credential caching has been implemented

The Keystone S3 credential caching feature permits using AWSv4 request signing (AWS_HMAC_SHA256) with Keystone as an authentication source, and accelerates Keystone authentication using S3. This also enables AWSv4 request signing, which increases client security.

nfs-ganesha has been updated to the latest version

The nfs-ganesha package is now based on the upstream version 2.7.4, which provides a number of bug fixes and enhancements from the previous version.

OSD BlueStore is now fully supported

BlueStore is a new back end for the OSD daemons that allows for storing objects directly on the block devices. Because BlueStore does not need any file system interface, it improves performance of Ceph Storage Clusters.

A new configuration option: osd_map_message_max_bytes

The monitoring function can sometimes send messages via the Ceph File system kernel client to the cluster which are too large, causing a traffic problem. A configuration option named osd_map_message_max_bytes was added with a default value of 10MiB. This allows the cluster to respond in a more timely manner.

The default BlueStore and BlueFS allocator is now bitmap

Previously, the default allocator for BlueStore and BlueFS was the stupid allocator. This allocator spreads allocations over the entire device because it allocates the first extent it finds that is large enough, starting from the last place it allocated. The stupid allocator tracks each extent in a separate B-tree, so the amount of memory used depends on the number of extents. This behavior causes more fragmentation and requires more memory to track free space. With this update, the default allocator has been changed to bitmap. The bitmap allocator allocates based on the first extent possible from the start of the disk, so large extents are preserved. It uses a fixed-size tree of bitmaps to track free space, thus using constant memory regardless of number of extents. As a result, the new allocator causes less fragmentation and requires less memory.

osdmaptool has a new option for the Ceph upmap balancer

The new --upmap-active option for osdmaptool command calculates and displays the number of rounds that the active balancer must complete to optimize all upmap items. The balancer completes one round per minute. The upmap.out file contains a line for each upmap item.

Example

$ ceph osd getmap > mymap
got osdmap epoch ####
$ osdmaptool --upmap upmap.out --upmap-active mymap
osdmaptool: osdmap file 'mymap'
writing upmap command output to: upmap.out
checking for upmap cleanups
upmap, max-count 10, max deviation 5
pools .......
....
prepared 0/10 changes
Time elapsed ####### secs
Unable to find further optimization, or distribution is already perfect
osd.0 pgs ###
osd.1 pgs ###
osd.2 pgs ###
.....
Total time elapsed ######### secs, ## rounds

The ability to inspect BlueStore fragmentation

This update adds the ability to inspect fragmentation of the BlueStore back end. To do so, use the ceph daemon command or the ceph-bluestore-tool utility.

Updated the Ceph debug log to include the source IP address on failed incoming CRC messages

Previously, when a failed incoming Cyclic Redundancy Check (CRC) message was getting logged into the Ceph debug log, only a warning about the failed incoming CRC message was logged. With this release, the source IP address is added to this warning message. This helps system administrators identify which clients and daemons might have some networking issues.

New omap usage statistics per PG and OSD

This update adds a better reporting of omap data usage on a per placement group (PG) and per OSD level. PG-level data is gathered opportunistically during a deep scrub. Additional fields have been added to the output of the ceph osd df and various ceph pg commands to display the new values.

Listing RADOS objects in a specific PG

The rados ls command now accepts the --pgid option to list the RADOS objects in a specific placement group (PG).

PG IDs added to omap log messages

The large omap log messages now include placement group IDs to aid in locating the object.

The rocksdb_cache_size option default is now 512 MB

BlueStore OSD rocksdb_cache_size option default value has been changed to 512 MB to help with compaction.

The RocksDB compaction threads default value has changed

The new default value for the max_background_compactions option is 2. As a result, this change improves performance for write heavy OMAP workloads. This option controls the number of concurrent background compaction threads. The old default value was 1.