HP (Hewlett-Packard) QR516B Computer Accessories User Manual


 
NOTE: VAAI Plugin 2.2.0 is required if the ESXi 5.x server is connected to two or more arrays
that are running a mix of OS HP 3PAR OS 2.3.1.x and OS 3.1.x. For LUNs on HP 3PAR OS
3.1.x, the default VMware T10 plugin will be effective, and for storage LUNs on HP 3PAR OS
2.3.x, HP 3PAR VAAI Plugin 2.2.0 will be effective.
For more information, refer to the HP 3PAR VAAI Plug-in Software for VMware vSphere User's
Guide (HP part number QL226-96072).
To download the HP 3PAR VAAI Plugin software, go to:
https://h20392.www2.hp.com/portal/swdepot/displayProductInfo.do?
productNumber=HP3PARVAAI&jumpid=reg_r1002_usen
UNMAP (Space Reclaim) Storage Hardware Support for ESXi 5.x
HP 3PAR OS 3.1.1 or later supports the UNMAP storage primitive for space reclaim, which is
supported starting with ESXi 5.0 update 1 with default VMware T10 VAAI plugin. Installation of
the HP 3PAR VAAI plugin is not required.
NOTE: To avoid possible issues described in VMware KB 2007427 and 2014849, automatic
VAAI Thin Provisioning Block Space Reclamation (UNMAP) should be disabled on ESXi 5.0 GA.
The KB articles are available on the VMware Knowledge Base website:
http://kb.vmware.com
ESXi 5.0 update 1 and later includes an updated version of vmkfstools that provides an option
[-y] to send the UNMAP command regardless of the ESXi host’s global setting. You can use the
[-y] option as follows:
# cd /vmfs/volumes/<volune-name>
vmkfstools -y <percentage of deleted block to reclaim>
NOTE: The vmkfstools -y option does not work in ESXi 5.0 GA.
UNMAP will also free up space if files are deleted on UNMAP-supported VMs such as Red Hat
Enterprise 6, provided it is a RDM LUN on a TPVV storage volume-—for example, for RDM volumes
on a Red Hat VM using the ext4 filesystem and mounted using the discard option.
# mount t ext4 o discard /dev/sda2 /mnt
This will cause the RH6 VM to issue the UNMAP command and cause space to be released back
on the array for any deletes in that ext4 file system.
Out-of-Space Condition for ESX 4.1 and ESXi 5.x
The out-of-space condition, aka "VM STUN", is implemented in ESX 4.1 and ESXi 5.x and is
supported as of HP 3PAR OS 2.3.1 MU2. This OS feature has no dependency on the VAAI plugin
and applies to TPVV volume types.
When the TPVV volume cannot allocate additional storage space or cannot grow because the
storage system has run out of disk space, it sends Check condition with "DATA PROTECT" sense
key hard error and additional sense "SPACE ALLOCATION FAILED WRITE PROTECT". As a result,
ESX pauses the VM and displays an 'Out of Space' message to the user in the Summary tab of
the VM on vSphere, with the options of Retry or Cancel. In the pause-VM condition, read requests
and rewrites to the allocated LUN blocks are allowed, but writing to a new space is not allowed.
Ping, telnet and ssh requests to the VM are not honored. The storage administrator needs to add
additional disk space or use storage vMotion to migrate other unaffected VMs from the LUN. After
ESX/ESXi 4.1, ESXi 5.x Additional Feature Considerations 53