The esxcli unamp command is an useful tool for reclaiming space from thin provisioned LUNs, more details on the command and it’s use can be found in this VMware KB article: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2057513 The version of vSphere we use is 5.5 and I have ran this command and reclaimed space before without any issues, however, on one particular LUN […]