Problem: Internal Server Error in "uvmm/domain/put"

Problem

While logged in to UMC in the UVMM module an error occured “internal server error”.

Investigation

The logfile shows the following entries:

Interner Server-Fehler in "uvmm/domain/put".
AttributeError: 'NoneType' object has no attribute 'status'
    success = result.status == 'OK'
  File "/usr/lib/pymodules/python2.7/univention/management/console/modules/uvmm/uvmmd.py", line 113, in response
    return self.response(data)
  File "/usr/lib/pymodules/python2.7/univention/management/console/modules/uvmm/uvmmd.py", line 106, in request
    return self._function( *tmp, **self._kwargs )
  File "/usr/lib/pymodules/python2.7/notifier/__init__.py", line 104, in __call__
    tmp = self._function()
  File "/usr/lib/pymodules/python2.7/notifier/threads.py", line 82, in _run
Traceback (most recent call last):

Request: uvmm/domain/put
Interner Server-Fehler in "uvmm/domain/put".

On the host a very demanding rsync task was running putting a very high load of I/O waits to the server’s hardware. This led to the delayed responses of UVMM.

Solution

Start your task with ionice:

ionice -c3 rsync ...

This will make sure other processes get higher IO priority when needed.