Server crashes after some time?

I have a problem with my gmod server. The server crashes, let’s say every 1 hour with the error: ‘Segmentation fault’. Maybe you can help me with this.
I found an error in the startup log:

Updating server using Steam.
Redirecting stderr to '/root/Steam/logs/stderr.txt'
[  0%] Checking for available updates...
[----] Verifying installation...
[----] !!! Fatal Error: Failed to load
Tue Aug 19 11:43:25 CEST 2014: Steam Update failed, ignoring.

Hopefully, you can help me.