Datastore unmount error: Cannot unmount volume because file system is busy

Just this week ran into this issue while trying to unmount some stale datastore from vCenter server.

Troubleshooting:

SSH into the ESXi host and browse the datastore.
On the datastore I found the following files listed with following names:
vsantraces*

Found KB 2069171 specifying this problem where the VSAN modules stores the traces needed to debug VSAN related problems which is keeping a lock on the datastore.

Resolution:

Since we are not using VSAN I had to disabled the VSAN services on the ESXi host to remove the datastore.

  • To verify open files for vsantrace:
    • lsof | grep vsantraced | grep volumes
  • Run command to stop services:
    • /etc/init.d/vsantraced stop
  • Perform a Refresh for Storage
  • Unmount the datastore
  • Run command to start the services: 
    • /etc/init.d/vsantraced start

If you are however using VSAN then you need to change the trace location with the following command:
esxcli vsan trace set -p

To verify open files for vsantrace
lsof | grep vsantraced | grep volumes

On a side note:

Initially the unmount of the datastore still did not exceed and this was due to my SSH sessions which has the datastore open 🙂 Close the SSH session before trying to unmount.

You could potentially still have problem with unmount when following scenario exists: 
  • Scratch for host is configured on the problem datastore. Modify the ScratchConfig value and change it to another datastore. For more information, see Creating a persistent scratch location for ESXi 4.x and 5.x (1033696).
  • Coredump is configured to write to a file in the problem datastore in an ESXi 5.5 host. For more information see, Move the coredump to a File from the VMware vSphere 5.5 documentation Center.
    • Run following command to check for paths:
      • esxcli system coredump file list
    • Verify the UUID and compare to datastore name.
    • Run following command to remove the coredump files. 
      • esxcli system coredump file remove –force
Links:

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s