So how can a datastore be deleted if there is an active file in a vmkdump folder that resides in the datastore running Vsphere Client and ESX 5.x?
When browsing the datastore, a vmkdump folder shows up with a file in it, this file is in use and prevents the datastore to be deleted, it is a log dump file and in my case could be remove and re-added safely to another store.
The files cannot be migrated by the Vsphere Client and trying to do so or delete dem gives an error: “Device or resource busy”
One .dumpfile is created by each host in a random datastore, and to delete and recreate them, you have to find the owner of the file, to do so, take the ID of the file and log in to your hosts by this adress to find their ID which have to match the filename:
then logon to the ESX host with putty, and run this command: “esxcli system coredump file remove –F”
Then recreate the file at a new destination with: “esxcli system coredump file add -f SERVERNAME -d DATASTORENAME”
Make the file active: “esxcli system coredump file set -p /vmfs/volumes/DATASTORE_UUID/vmkdump/FILENAME”
Run this command to see if the file is active: “esxcli system coredump file list”
So to solve this puzzle, these to blogs did the math.