Friday, June 20, 2014

Things to look out for when using VMware PVSCSI

Well, since VMXNET3 is optimum, why not PVSCSI?

Rolling out to a production environment we have to make sure we know the possible caveats and limitations so that the stakeholders can be informed and operations have the correct information for deployments.

Following is a summary of things to look out for based on URL here:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1010398


  • The VMware PVSCSI adapter driver is also compatible with the Windows Storport storage driver
  • PVSCSI adapters are not suited for DAS environments.
  • Cannot be used as a boot disk for Red Hat Enterprise Linux (RHEL) 5 (32 and 64 bit) and all update releases
  • Hot-adding a PVSCSI adapter is only supported for those versions that support booting from a PVSCSI adapter.
  • Hot add or hot remove requires a bus rescan from within the guest.
  • Disks with snapshots might not experience performance gains when used on Paravirtual SCSI adapters if memory on the ESX host is over committed.
  • Do not use PVSCSI on a virtual machine running Windows with spanned volumes. Data may become inaccessible to the guest operating system.
  • If you upgrade from RHEL 5 to an unsupported kernel, you might not be able to access data on the virtual machine's PVSCSI disks. You can run vmware-config-tools.pl with the kernel-version parameter to regain access.
  • If a virtual machine uses PVSCSI, it cannot be part of a Microsoft Cluster Server (MSCS) cluster.
I remember seeing somewhere some other considerations for View deployments and will update this post once there is more information.

Have a great day ahead!