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Upgrading to VMFS 5 and Expanding a Volume

With so many things being upgraded, it’s hard to keep track of the actual benefits to each one. The VMFS 5 upgrade has some pretty substantial upgrades, including: a unified block size at 1MB (no more volume size limitations due to block size), the extent volume size limit has been increased and can theoretically go near 60TB on a single extent volume, smaller sub-blocks (down to 8KB from the previous 64KB), pass-through RDMs can approach the 60TB limit, etc.

There are still some limitations though, unfortunately the VMDK size limit remains at 2TB, virtual RDMs also remain with a 2TB size limit, and the LUN limit remains at 256.

To start the upgrade, go to the datastore which needs upgrading and click on the “Upgrade to VMFS-5” link:

The system will check to verify that all hosts whom have connection to the selected datastore can access the VMFS-5 version:
Check for ESXi5

After clicking “OK” to start the upgrade, the datastore will upgrade and then all the hosts connected to it will rescan for VMFS volumes:

Clicking back on the datastore, the version will have been updated. In this case it was to VFMS 5.54.
Updated Datastore

With the new features of VMFS-5, I think increased the volume to the 5TB limit which was set on the SAN. Click on the “Properties” of the Datastore, and then click on the “Increase” button:
Datastore Properties

Select the same datastore to extend the extent, click “Next”, verify the current layout, click “Next”
Select Current Device
Review Disk

Select the amount of space to expand the datastore to, select “Next”, then verify the information and click “Finish”
Expand Size

The tasks will computer and expand the datastore, then have all the hosts rescan for VMFS volumes

After the tasks complete, it’s all done and ready to go.
Datastore Properties
Datastore Details

Upgrading from VMFS 3 to 5 was quite smooth, the VMs kept running, and nothing was noticed. The same can be said for the expansion, everything went smooth. One thing I would recommend is creating a VMFS 5 extent volume and Storage vMotioning from the VMFS 3 extent to the VMFS 5 extent.

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  1. ela2014 ela2014

    in my network i have vsphere server 4.1 and i want upgrade to 5.what happen if i want vmfs 3 upgrade to vmfs 5 for my VMs in vsphere?

    • Problem Problem

      You get all the benefits that VMFS5 brings to the table (the smaller 1MB block size and so forth). About the only reason I can think that you wouldn’t want to upgrade would be if you’re running a mixed environment, because VMFS5 only works with ESXi5.

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