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1.36.  device-mapper-multipath

1.36.1.  RHBA-2009:0432: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2009:0432
Updated device-mapper-multipath packages that resolve an issue are now available.
The device-mapper multipath packages provide tools to manage multipath devices by issuing instructions to the device-mapper multipath kernel module, and by managing the creation and removal of partitions for device-mapper devices.
These updated device-mapper-multipath packages fix the following bug:
  • there was a race condition in the shutdown code for multipathd wherein a lock could be destroyed before all threads were finished using it. This could cause the machine to become unresponsive on multipathd shutdown. The multipathd daemon now waits for all threads to finish using the lock before destroying it, thus removing the race and resolving the issue.
  • when adding a new multipath-capable block device, a race condition existed between the multipathd daemon and udev to multipath the new device. If udev--through multipath--updated the multipath devices first, then the multipathd daemon would not use the device-specific configurations for the device when it started monitoring the path. With this update, multipathd now correctly configures the device, even when udev notices it first, thus resolving the issue.
All users of device-mapper-multipath are advised to upgrade to these updated packages, which resolve this issue.

1.36.2.  RHSA-2009:0411: Moderate security update

Important

This update has already been released (prior to the GA of this release) as the security errata RHSA-2009:0411
Updated device-mapper-multipath packages that fix a security issue are now available for Red Hat Enterprise Linux 4 and 5.
This update has been rated as having moderate security impact by the Red Hat Security Response Team.
The device-mapper multipath packages provide tools to manage multipath devices by issuing instructions to the device-mapper multipath kernel module, and by managing the creation and removal of partitions for device-mapper devices.
It was discovered that the multipathd daemon set incorrect permissions on the socket used to communicate with command line clients. An unprivileged, local user could use this flaw to send commands to multipathd, resulting in access disruptions to storage devices accessible via multiple paths and, possibly, file system corruption on these devices. (CVE-2009-0115)
Users of device-mapper-multipath are advised to upgrade to these updated packages, which contain a backported patch to resolve this issue. The multipathd service must be restarted for the changes to take effect.
Important: the version of the multipathd daemon in Red Hat Enterprise Linux 5 has a known issue which may cause a machine to become unresponsive when the multipathd service is stopped. This issue is tracked in the Bugzilla bug #494582; a link is provided in the References section of this erratum. Until this issue is resolved, we recommend restarting the multipathd service by issuing the following commands in sequence:
# killall -KILL multipathd
# service multipathd restart

1.36.3.  RHBA-2009:0283: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2009:0283
Updated device-mapper-multipath packages that fix a bug are now available.
The device-mapper-multipath packages provide tools to manage multipath devices by giving the device-mapper multipath kernel module instructions on what to do, as well as by managing the creation and removal of partitions for device-mapper devices.
  • multipath must be able to open a file descriptor for each path that it monitors, plus 32 other file descriptors. By default, multipath can open 1024 file descriptors, which is sufficient for it to monitor 992 paths. If multipath is not able to open all the file descriptors that it needs, the multipath daemon will not function correctly, and in Red Hat Enterprise Linux 5.3, this situation exposes a kernel memory leak that can cause a system to stop responding. Previously, multipath would not warn users that it could not open enough file descriptors. Now, when multipath runs out of file descriptors, it prints an error message. System administrators can allow multipath to open more file descriptors by setting "max_fds" in the multipath.conf file to a sufficiently high number, or by setting "max_fds" to "max" to allow multipath to open as many file descriptors as the system allows.
Users are advised to upgrade to these updated device-mapper-multipath packages, which resolve this issue.

1.36.4.  RHEA-2009:1377: bug-fix and enhancement update

Updated device-mapper-multipath packages that fix several bugs and add various enhancements are now available.
The device-mapper-multipath packages provide tools to manage multipath devices using the device-mapper multipath kernel module.
This update applies the following bug fixes:
  • Occasionally multipathd was ignoring a device's hardware type when configuring it after a path was added.
  • Multiple documentation errors were fixed.
  • Multipathd would occasionally hang or crash while shutting down.
  • Multipath would always return a failure exit code when removing a device with multipath -f/-F.
  • Multipathd wouldn't free its resources when it failed to execute a callout.
  • Multipathd would always return a success exit code for interactive commands, even if the command failed or was invalid.
  • The mpath_prio_alua pritority callout was failing on some setups because a buffer was too small.
  • Multipathd was holding mount points in the /etc directory busy, even after they were unmounted.
  • Multipath and multipathd were racing to create the mulitpath devices for newly added block devices. This was causing device creation to take a long time on some systems, and could even cause devices to have incorrect configurations.
This update adds the following enhancements:
  • Default configurations were added for the Compellent Storage Center and the IBM DS3200, DS3300, DS4700, and DS5000.
  • It is now possible to set the verbosity level for the multipath and multipathd commands in /etc/multipath.conf.
  • The TUR path checker retries on more transient errors, so that multipathd will not fail a path due to a transient error.
  • There is a new priority callout mpath_prio_intel to support the Intel Modular Server.
  • There is now a multipath.conf.5 man page that explains the /etc/multipath.conf configuration file.
All users are advised to upgrade to these updated packages, which resolve these issues and add these enhancements.

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