ESXi – unable to complete sysinfo operation when unmounting NFS datastore

I am currently trying to prepare a old NetApp filer (FAS960C) for a cold hard life in the scrap yard.

I thought it would be as simple as storage vmotioning all the VMs off it, and then simply unmounting the datastore from vSphere. Unfortunately I get this message when trying to unmount the darn thing.

what the heck does this mean?

So the error message says see the VMKernel log. I enable ssh on the host and check out /var/log/messages. [na] is the name of my datastore.

GFeb 12 06:34:33 vmkernel: 0:00:57:57.020 cpu11:5646)WARNING: NFS: 1675: na has open files, cannot be unmounted


So which files does it have open?!? I have removed all the VMs. This was the tricky part – on a normal Linux box, you would run lsof and in two seconds you would know which process using the files. In ESXi, you go:


esxcli network connection list | grep datastore ip/hostname


This returns the following :


/vmfs/volumes/c87b8682-017488df # esxcli network connection list | grep 10.0.0.10
tcp 0 0 10.0.0.45:1014 10.0.0.10:2049 ESTABLISHED 5163
tcp 0 0 10.0.0.45:1013 10.0.0.10:2049 ESTABLISHED 5163


The first IP column is the host, the second is the datastore. The last column is the world ID , which is like a PID. So plugging this into ps gives me:

/vmfs/volumes/c87b8682-017488df # ps aux | grep 5163
5163 5163 busybox syslogd


Well there you go – it looks like we have set this up this machine to use the Netapp as a place to store logs. Completely forgot I ever did that! A quick check of the software -> advanced settings dialog reveals this is the case:

Clearing that dialog and a quick reboot will fix that.