We have all ran into this problem. You try to unmount a datastore and it fails. The unmount prechecker does not show any virtual machines. You don’t have any ISO’s mounted. You do see a directory called vsan and some files with a name something like this:
vsantraces--some-date.gz
But wait you are not running vsan. You do have 5.5 installed. Well guess what. Trace files for vsan are being stored anyways. You can locate the process with lsof (list open files):
lsof | grep vsantrace
This will produces lots of processes using these files. At the end of the day you can break the lock by logging into the ESXi host and running the following command:
/etc/init.d/vsantraced stop You can also stop the process from starting after a reboot with the following command:
chkconfig vsantraced off
I wish you could use the powercli method to shut it down but it does not yet work. You have to login to each host and shutdown.
In order to login to all your ESXi hosts and change this variable you might want to use public keys and a ssh all script. You can read more about vsantraces in this kb.