Hi all, is there an online way to write zeroes to all free space on a VMFS volume? We have a lot of volumes on top of flash-based storage that does data reduction (compression + dedupe), so as VM's have come and gone, the storage of course reflects more physical space used than what is really used. We're zero'ing at the guest level too (already doing thick eager provisioned) to reclaim space cleared up within the VMDK's, but would like to run a cleaning on the VMFS volumes too so we can get a real number on how much space is being used on the arrays.
Hello hostasaurus,
If they are thin-provisioned LUNs you should be able to achieve this using vmkfstools -y (ESXi 5.0-5.1):
kb.vmware.com/kb/2014849
or
esxcli storage vmfs unmap (ESXi 5.5-6.5):
kb.vmware.com/kb/2057513
Bob
Hello,
It is very likely that your storage vendor has developed a vCenter plugin for UNMAP, so you can schedule/automate reclamation to run against your VMFS datastores on a regular basis.