Citrix XenServer 5.5 Update 1

Citrix release today the first update for XenServer 5.5 :

Changes included in this update
LVHD Snapshots
When LVHD snapshots are deleted, disk space is reclaimed by freeing unused snapshot data. This is provided automatically by XenServer while VMs continue to run. However, there is a known limitation in the 5.5 implementation of this feature: when all snapshots are deleted for a given VM?s disks, some disk space allocated to these snapshots may remain. To address this limitation, Update 1 includes an ‘Off-line Coalesce’ tool that can reclaim all disk space previously allocated to deleted snapshots while the VM is temporarily set offline. The Off-line Coalesce tool and its use are described in full in an associated KB article: CTX123400.

XenCenter Improvements
CA-30569, CA-32164, CA-30200

Fixed various ‘Application Errors’ in XenCenter.



XenCenter saved searches are now visible under ‘Apply Saved search’ and ‘Delete saved search’ options.



Big improvements to XenCenter performance when connecting to multiple pools.




Snapshot errors after upgrade from 5.0 to 5.5. Previously released as hotfix XS55E001 and documented in KB article CTX122142.



When multipathing is disabled, then this information is now correctly displayed in XenCenter.



The XenCenter New Storage Wizard now works as expected when multipath is enabled.



Legacy LVM VDIs (created on versions of XenServer prior to 5.5) greater than 2TB in size now work after upgrade to 5.5 as expected.



The multipath path-checker has been improved for Pillar Data arrays to make it more resilient to transient path failures.



Importing VMs preserves sparseness where possible.



When taking a snapshot of a legacy LVM VDI (created with a previous version of XenCenter) and then deleting this snapshot, then the deleted snapshot is now coalesced into the LVM VDI to reclaim space as expected.



SR.scan on NetApp SRs inadvertently caused snapshots created externally to XenServer (e.g. those created using a utility like SnapMirror) to be deleted. This caused utilities such as SnapMirror to fail when used with the NetApp SR. This issue is now fixed: SR.scan will only remove snapshots created by XenServer. As a result utilities such as SnapMirror will work as expected.



SRs with non-ASCII characters in their names now work as expected.


Active Directory Improvements

Memory leak in dom0 components used to manage Active Directory integration fixed.



When disabling AD in XenCenter, an application error is no longer generated if the wrong domain credentials are supplied.



AD authentication via XenServer now works as expected even if the password contains a space.



In large Active Directory (AD) databases (containing thousands of users belonging to many groups), the XenServer authentication became slow, and occasionally the XenServer component querying the AD crashed. Both these issues are resolved.



AD authentication via XenServer will now always work as expected, even if one or more of the domains is offline.


General System Improvements

The Windows time is correctly preserved when lifecycle operations are performed on VMs. Previously released as Hotfix XS55E003 and documented in KB article CTX122589.



VM clocks no longer drift significantly, even with multiple vCPUS and under heavy load.



‘xe pool-certificate-install’ and ‘xe pool-certificate-uninstall’ now work as expected.



Fixed domain crash that sometimes occurred during live migrate of a multi-vCPU Windows Server 2008 64 bit VM on an EPT server with Hyperthreading enabled. Previously released as Hotfix XS55E002 and documented in KB article CTX122348.



VMs no longer crash when running on Intel servers with EPT enabled and one selects the ‘switch to remote console’ option in XenCenter. Previously released as Hotfix XS55E004 and documented in KB article CTX122705.



The Debian Lenny kernel installed by XenServer tools now has a configuration based on the standard Debian kernel meaning the configuration will be closer to the expected one from a Debian installation on physical hardware. Users may update to the new kernel by re-installing the tools.


CA-33213, CA-33237

Fixed issues that may result in crashes during live migration of Windows VMs.



VM performance metrics are now always preserved correctly (and hence always displayed correctly in XenCenter) across live migrate.



Attempting to create a NIC bond on a pool slave from XenCenter would sometimes fail silently, leaving the bond uncreated. This issue is now fixed.


Installing the update
Customers should use either XenCenter or the xe CLI to install this update. Once the update has been installed, in order for it to take effect, the server must be restarted. As with any software update, please back up your data before applying this update.


Note: After installing Update 1 on your XenServer pool you will need to update the XenServer Tools in all virtual machines. The steps below explain how to do this.


Installing the update using XenCenter
1.       Download the update to a known location on a computer that has XenCenter installed.

2.       In XenCenter, on the Tools menu, select Install New Update.

3.       Select the servers you wish to update.

Citrix advises to update all hosts in a pool within a short space of time. Running a mixed pool of updated and non-updated hosts for general operation is not supported. Click Next to proceed in the wizard.

4.       Enter the path to browse to the downloaded update file. Click Next and the update will be uploaded to the pools and servers you chose to update.

5.       Click Finish. (You will need to use manual mode as this update does not support automated modes.) The update will now be applied to each server.

6.       After the update is installed on all servers then reboot each server.

7.       Using XenCenter, update the XenServer Tools on all VMs.


To update XenServer Tools on Linux VMs
Note: Installing XenServer Tools will cause anything in the virtual machine’s CD/DVD-drive to be ejected. Do not attempt to install XenServer Tools if the virtual machine’s CD/DVD-drive is in use, for example, during OS install from CD.

1.       Select the VM in the Resources pane.

2.       Click the Console Tab.

3.       Select xs-tools.iso from the DVD Drive drop-down list.

4.       As the root user, mount the image into the VM:

mount /dev/xvdd /mnt

5.       Execute the installation script as the root user:


6.       Reboot your VM.


Installing the update using the off-host CLI
1.       Download the update to a known location on a computer that has the XenServer CLI installed.

2.       Upload the patch to the pool or host you wish to apply it to:

$ xe -s <server> -u root -pw <password> patch-upload file-name=<filename>

This causes the update identifier to be printed to the screen:


3.       Apply the patch to the pool, specifying the UUID of the patch, as given by the upload command in the previous step:

$ xe -s <server> -u root -pw <password> patch-pool-apply \


4.       In order to complete the application of the patch, restart the hosts in the pool.

5.       Using XenCenter, update the XenServer Tools on all VMs.


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