Who Should Install This Hotfix?
This is a hotfix for customers running Citrix XenServer 6.0.2.
IMPORTANT: This hotfix updates the control domain (dom0) kernel version. The driver disks issued for Hotfix XS602E028 are compatible with this hotfix.
Issues Resolved In This Hotfix
This hotfix resolves the following issues:
- Running XAPI plugins that generate more than 300 KB of data on a pool member can cause the pool member to disconnect from the Pool Master.
- In an environment where Linux bridge is used as the network stack, and the XAPI database is corrupted, creating and deleting VLANs on a regular basis can cause multiple VLANs to be present on the same bridge. This can eventually lead to a network loop.
- VM import tasks running for more than 24 hours will fail. This is due to a bug which prematurely times out XAPI sessions and deletes all pending tasks that are older than 24 hours.
- In environments where High Availability (HA) is enabled, if a XenServer host crashes and immediately recovers, VMs running on the host can fail to start with an SR_BACKEND_FAILURE error message. This is due to a race condition that allows VMs to be started on the host, even before the host has joined the liveset.
- Migrating Virtual Machines (VMs) can cause memory corruption in the HVM domain due to a bug in the Paravirtualized (PV) console setup.
- An issue in the VM Protection and Recovery (VMPR) implementation can cause host corruption and affect the stability of the pool.
- Attempts to create a new Virtual Disk Image (VDI) can fail. This is due to a bug that fails to delete lock directories when VDIs are destroyed. When this happens, the VDI lock directories at /var/lock/sm can eventually fill up preventing the Pool Master from creating a lock directory for the new VDI.
- In some cases, Multipathing is shown as 'Not active' in XenCenter even when there are active paths present in the corresponding storage repository (SR).
- LVM-based SRs (for example, LVMoHBA, LVMoiSCSI, and LVM) incorrectly allow customers to create VHD files that are up to 2048 GB in size and file-based SRs (for example, NFS and EXT) allow customers to resize VHD files that are up to 2048 GB in size. However, writing more than 2043 GB of data to the VDIs can lead to a VDI corruption. Installing this hotfix ensures VMs with VDIs that contain more than 2043GB of data get I/O errors, and thereby eliminates the chances of a silent VDI corruption.
- In environments where IntelliCache is enabled, deleting or replacing the master VDI does not delete the associated cache file in the local SR. This can eventually lead to an accumulation of unused cache files which can consume a large amount of disk space in the local SR. This hotfix provides an automated way to delete the unused cache files after they reach the maximum time.
To delete the unused cache files on the XenServer host, run the following command:
<SR_UUID>refers to the UUID of the local SR and
<max_hours>refers to the maximum time in hours after which any unused cache files will be deleted.
In addition, this hotfix contains the following improvements:
- Installing this hotfix reduces the use of event channels in the control domain (dom0) by one event channel per Windows VM. This enables customers to increase the number of Windows VMs that can be started on a XenServer host.
- Copying a virtual disk between SRs will now use unbuffered I/O to avoid polluting the pagecache in dom0. This lowers the dom0 vCPU overhead and allows the pagecache to work more effectively for other operations.
This hotfix also includes the following previously released hotfixes:
- CTX132823 – Hotfix XS602E001 - For XenServer 6.0.2
- CTX133166 – Hotfix XS602E003 - For XenServer 6.0.2
- CTX133812 – Hotfix XS602E005 - For XenServer 6.0.2
- CTX134479 – Hotfix XS602E007 - For XenServer 6.0.2
- CTX135303 – Hotfix XS602E011 - For XenServer 6.0.2
- CTX135623 – Hotfix XS602E013 - For XenServer 6.0.2
- CTX136479 – Hotfix XS602E021 - For XenServer 6.0.2
- CTX138631 – Hotfix XS602E027 - For XenServer 6.0.2
- CTX138921 – Hotfix XS602E028 - For XenServer 6.0.2
Installing the Hotfix
Customers should use either XenCenter or the XenServer Command Line Interface (CLI) to install this update. Once the update has installed, the server must be restarted for it to take effect. As with any software update, please back up your data before applying this hotfix. Citrix recommends updating all hosts within a pool sequentially. Upgrading of hosts should be scheduled to minimize the amount of time the pool runs in a "mixed state" where some hosts have been upgraded and some have not. Running a mixed pool of updated and non-updated hosts for general operation is not supported.
NOTE: The attachment to this article is a zip file. It contains both the hotfix update package, and the source code for any modified open source components. The source code is not necessary for hotfix installation: it is provided to fulfil licensing obligations.
Installing the update using XenCenter
- Download the update to a known location on a computer that has XenCenter installed.
- In XenCenter, on the Tools menu, select Install New Update. This displays the Install Update wizard.
- Click Next to start the Wizard.
- Click Add to upload a new update.
- Browse to the location where you downloaded the hotfix, select it, and then click Open.
- From the list of updates select XS602E030.xsupdate and then click Next.
- Select the hosts you wish to apply the hotfix to, and then click Next.
- Follow the recommendations to resolve any upgrade prechecks and then click Next.
- Choose how to perform post-update tasks. In the Post update options section, select automatically or manually, and then click Install update.
- When the installation process is complete, click Finish to exit the wizard.
- Customers who selected to manually perform the post-update tasks, must ensure to do so after installing the hotfix.
- If customers selected to automatically perform the post-update tasks, the XenCenter controlled upgrade process reboots each host sequentially starting with the Pool Master, where possible VMs will be migrated to other running hosts to avoid VM downtime. When the Pool Master is being rebooted, XenCenter will be unable to monitor the pool.
Installing the update using the xe Command Line Interface
- Download the update file to a known location.
- Extract the xsupdate file from the zip.
- Upload the xsupdate file to the Pool Master by entering the following commands:
(Where hostname is the Pool Master's IP address or DNS name.)
xe patch-upload -sXenServer assigns the update file a UUID which this command prints. Note the UUID.
<hostname>-u root -pw
- Apply the hotfix to all hosts in the pool, specifying the UUID of the hotfix:
<hostname>-u root -pw
- Verify that the update was applied by using the patch-list command.
xe patch-list -sIf the update has been successful, the hosts field will contain the UUIDs of the hosts this patch was successfully applied to. This should be a complete list of all hosts in the pool.
<hostname>-u root -pw
- To verify in XenCenter that the update has been applied correctly, select the Pool, and then click the General tab. This displays the Pool properties. In the Updates section, ensure that the update is listed as Applied.
- The hotfix is applied to all hosts in the pool, but it will not take effect until each host has been rebooted. For each host, migrate the VMs that you wish to keep running, and shut down the remaining VMs before rebooting the host.
|Hotfix File md5sum||f5c86759c1055190bd8adb2129b0bccb|
|Hotfix Source Filename||XS602E030-src-pkgs.tar.bz2|
|Hotfix Source File md5sum||fdcdeb571a8b951405be698dc2bcf817|
|Hotfix Zip Filename||XS602E030.zip|
|Hotfix Zip File md5sum||1c68e9957989cc1ca233dbf78c470a41|