vSphere 5.5 – what’s new – storage

On VMworld 2013 in San Francisco VMware announced new version of vSphere in 5.5 version.

what’s new in storage ? Many things such a vSAN, large VMDK files support and more read more for details.

  1. Finally !!! – support for bigger VMDK than 2TB -512b , so now is 64TB support – nice.
  2. Full support for 16GB end2end support – in previous versions of vSphere theoretically vSphere supports 16GB but it was throttled to 8GB – since vSphere 5.5 vSphere supports 16GB E2E
  3. Permanent Device Lost (PDL) autoremove – With vSphere 5.5, a new feature called PDL AutoRemove is introduced. This feature automatically removes a device from a host when it enters a PDL state. Because vSphere hosts have a limit of 255 disk devices per host, a device that is in a PDL state can no longer accept I/O but can still occupy one of the available disk device spaces. Therefore, it is better to remove the device from the host.
  4. vFlash-  yet another block for Software Defined Storage –  SDS. vSphere 5.5 introduces a new storage solution called vSphere Flash Read Cache, a new Flash-based storage solution that is fully integrated with vSphere. Its design is based on a framework that enables the virtualization and management of local Flash-based devices in vSphere. Long story short, in vSphere 5.5 localcy attached flash devices are integrated into storage stack. vSphere hosts consume the vSphere Flash Resource as vSphere Flash Swap Cache, which replaces the Swap to SSD feature previously introduced with vSphere 5.0

    vFlash

    vFlash

  5. MSCS improvements
    1. support for Windows 2012 in MSCS configuration
    2. iSCSI protocol for shared storage !!!! awesome in vSphere 5.5 you can use iSCSI protocole for shared storage in MSCS
    3. FCoE for shared storage – nice to have I would say 🙂
    4. Round Robin path policy – again – FINALLY
  6. vSphere Replication Interoperability – before vSphere 5.5 when storage vMotion moved replicated VM full VM replication had to be started in order to have VM replicated again. In vSphere 5.5 replicated VM can be moved by SDRS or storage vMotion without replication penalty – cool stuff.
  7. VAAI UNMAP Improvements
    vSphere 5.5 introduces a new and simpler VAAI UNMAP/Reclaim command: 

    As before, this command creates temporary files and uses UNMAP primitive to inform the array that these blocks in this temporary file can be reclaimed. This enables a correlation between what the array reports as free space on a thin-provisioned datastore and what vSphere reports as free space. Previously, there was a mismatch between the host and the storage regarding the reporting of free space on thin-provisioned datastores. There are two major enhancements in vSphere 5.5: the ability to specify the reclaim size in blocks rather than as a percentage value; dead space can now be reclaimed in increments rather than all at once.
  8. VMFS Heap Improvements
    In previous versions of vSphere, there was an issue with VMware vSphere VMFS heap: There were concerns when accessing open files of more than 30TB from a single vSphere host. vSphere 5.0 p5 and vSphere 5.1 Update 1 introduced a larger heap size to confront this. In vSphere 5.5, VMware introduces a much improved heap eviction process, so there is no need for the larger heap size, which consumes memory. vSphere 5.5, with a maximum of 256MB of heap, enables vSphere hosts to access all address space of a 64TB VMFS

Artur Krzywdzinski

Artur is Consulting Architect at Nutanix. He has been using, designing and deploying VMware based solutions since 2005 and Microsoft since 2012. He specialize in designing and implementing private and hybrid cloud solution based on VMware and Microsoft software stacks, datacenter migrations and transformation, disaster avoidance. Artur holds VMware Certified Design Expert certification (VCDX #077).