Failed unmounting /usr on boot

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Environment

SUSE Linux Enterprise Server 12 Service Pack 2 (SLES 12 SP2)

Situation

After an upgrade to SUSE Linux Enterprise Server 12 Service Pack 2 the following error message is observed on boot or in the /var/log/boot.log:

[FAILED] Failed unmounting /usr.

And 'journalctl' shows:

umount[958]: umount: /usr: target is busy

The system finishes booting and there appears to be no real harm to the system as /usr won't be unmounted. However the system should not even attempt to umount /usr at this stage.

(This is only shown when /usr is on a separate partition. Unless btrfs/snapshots is being used requiring /usr on the root file system, /usr can be on a separate partition.)

Resolution

The systemd update, systemd-228-126.1 released January 2017 includes the patch for the problem. Please install the recommended update.

Cause

Additional Information

Disclaimer

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