> It turned out to be a disk quota issue.

Sounds right. Glad you figured it out.


> BAD: the violation of the disk quota doesn't show up in user_beancounters

Ah, quite true.

At my work site, we use Nagios to monitor all of our VEs for general 
health, as we would any other systems: check the free space, make sure 
the database server is running, make sure that DNS is resolving, etc. 
Our VEs are leased out to untrusted customers who sometimes attempt 
amateur system administration, so some sanity/health checks are helpful 
on general principles. :)

-- 
Gregor Mosheh / Greg Allensworth
System Administrator, HostGIS cartographic development & hosting services
http://www.HostGIS.com/

"Remember that no one cares if you can back up,
  only if you can restore." - AMANDA