Does vSphere 5.1 support 4K bytes sector volume?
I have a 512 bytes sector volume (volume_01), some VMs are running on the volume. Today, I upgrade my Dell Equllogic firmware to v7 (this version support 4k bytes sector volume).
I plan to create a new 4k bytes sector volome(volume_02), and migrate the VMs in volume_01 into volume_02. I don't know whether the different kind of volume is a risk factor.
You mean hard-drives with 4kB sector-size? Yes, vSphere 5.1 does support it (I have one such a drive for local backups). It should not be any problem for VMFS5 filesystem because it uses block/sub-block size 1MB/8kB. So on vSphere-side you are OK...
But check if your disk/raid-controller supports drives with 4kB sector-size! Some older might not support it yet (at least not those that can not emulate 512B sectors)...