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4.32. device-mapper-multipath

Updated device-mapper-multipath packages that fix one bug are now available for Red Hat Enterprise Linux 5.
The device-mapper-multipath packages provide tools to manage multipath devices by using the device-mapper multipath kernel module, as well as by creating and removing partitions for Device-Mapper devices.

Bug Fix

BZ#729478
The multipath priority callout programs did not work correctly with CCISS (Compaq Command Interface for SCSI-3 Support) devices because the multipath utility was not able to convert the "!" character in the CCISS sysfs name to the "/" character in the CCISS device name. As a consequence, callout programs failed to set path priorities for these devices. The underlying code has been modified, and the multipath utility now supports the new "%c" wildcard for callout functions, and thus ensures the correct CCISS names conversion.
All users of device-mapper-multipath are advised to upgrade to these updated packages, which fix this bug.
Updated device-mapper-multipath packages that fix one bug are now available for Red Hat Enterprise Linux 5.
The device-mapper-multipath packages provide tools to manage multipath devices by giving the dm-multipath kernel module instructions on what to do, as well as by managing the creation and removal of partitions for Device-Mapper devices.

Bug Fix

BZ#728144
Previously, device-mapper-multipath was looking for a CCISS device information at the incorrect location in the sysfs file system. As a consequence, it was impossible to configure multipath on CCISS devices. This bug has been fixed, device-mapper-multipath now finds the device information properly in the described scenario, and multipath can now be properly configured on CCISS devices.
All users of device-mapper-multipath are advised to upgrade to these updated packages, which fix this bug.
Updated device-mapper-multipath packages that fix multiple bugs are now available for Red Hat Enterprise Linux 5.
The device-mapper-multipath packages provide tools for managing of multipath devices using the device-mapper multipath kernel module.

Bug Fixes

BZ#741664
If a multipath device was deleted while its path was being checked, the multipathd daemon did not abort the path check. Consequently, the multipath application terminated unexpectedly if it attempted to access the multipath device information. With this update, multipathd aborts the path check and the daemon no longer crashes in this scenario.
BZ#703501
Previously, the multipathd daemon was looking for Compaq Command Interface for SCSI-3 Support (CCISS) device information at an incorrect location in the sysfs file system. As a consequence, it was impossible to configure multipath on CCISS device. This bug has been fixed, device-mapper-multipath now finds the device information in the described scenario, and multipath can now properly configure CCISS devices.
BZ#702410
The multipathd daemon was printing warning messages on removal of non-multipath Device Mapper devices. With this update, the underlying code has been fixed and no warning messages are logged on removal of such devices.
BZ#737072
Previously, SCSI targets could time out on SCSI commands and consequently become unresponsive. This happened because the mpath_prio_alua priority callout used by the commands was set to five minutes. With this update, the callout timeout has been changed to one minute.
BZ#703277
The multipathd daemon maintains a list of essential directories it needs to be able to access from its private namespace at all times. When unmounting an unnecessary device, multipath checks if the device mount point is not in the list. Previously, multipathd did not check whether the directories listed were symbolic links to the devices and did not consider the devices mounted at the symlinked mount point to be necessary. Consequently, if such a device was marked as unnecessary, multipathd unmounted the device even though the location was listed as essential, because it was listed as a symbolic link. With this update, multipathd detects symbolic links to necessary devices in the list and the symlinked devices are not unmounted. This update also adds a new parameter, keep_dir, which allows users to specify directories that multipathd preserves in its private namespace.
BZ#655203
If the user attempted to delete a multipath device but failed because partitions of the device were in use, some of the device partitions remained deleted. With this update, if multipathd fails to delete the entire device, it restores any partitions, which were already deleted.
BZ#729478
The multipath priority callout programs did not work correctly with CCISS (Compaq Command Interface for SCSI-3 Support) devices because the multipath utility was not able to convert the exclamation mark (!) character in the CCISS sysfs name to the slash (/) character in the CCISS device name. As a consequence, the callout programs failed to set path priorities for these devices. The multipath utility now supports the new %c wildcard for callout functions and the CCISS names are converted correctly.
BZ#650795
The multipathd daemon returned incorrect path groupings for the multipath devices configured to use the group_by_node_name grouping policy. This was due to an incorrect reporting of the target node name for iSCSI targets. With this update, multipath checks the iSCSI target name if the FC (Fibre Channel) path check fails and the target name reporting works as expected.
BZ#716329
Previously, multipathd terminated unexpectedly if the file_timeout parameter was set to 0. With this update, multipathd uses the default file timeout of 90 seconds just as when the parameter is set to a negative value and the problem no longer occurs.
BZ#740512
The mpath_prio_alua callout occasionally failed. This happened because multipathd did not clean some of the buffers used to collect the SCSI data. With this update, the buffers are cleaned properly and the problem no longer occurs.
BZ#740022
Multipath commands failed on a multipath device if the current working directory contained a file with the same name as the multipath device name. This happened because multipathd assumed that the argument was referring to the file. Multipath now performs a check to prevent such an incorrect argument handling and the commands are executed as expected in this scenario.
BZ#655976
On a device set to manual failback, multipath was incorrectly failed back to the primary path group on a path's priority change. With this update, the device no longer fails back to the primary path group under these circumstances.
BZ#711970
Previously, the multipath default configuration defined the path selector using the selector key word, while device sections were using the path_selector key word. To ensure consistency, the default section now accepts both key words, the selector and path_selector.
BZ#719575
The kpartx utility built partition devices for GUID partition tables (GPT) with incorrect partition entry size. This happened because the utility did not validate the size of the GUID partitions. The kpartx utility now checks the size of the partitions, and partitions of an invalid GPT are no longer created.
BZ#715524
Previously, the default config value file_timeout was not documented. This update adds the respective documentation to the multipath.conf.annotated file.
All device-mapper-multipath users are advised to upgrade to these updated packages, which fix these bugs.