Maintained by: NLnet Labs

[Unbound-users] Unbound periodically stops responding

Will Roberts
Wed Apr 6 03:01:27 CEST 2011


Hi,

I'm using unbound 1.4.6 on 40ish machines, and for the most part it 
works fantastically. On one my machines however it seems to randomly 
stop responding. I'm not convinced the fault here lies with unbound, but 
as far as I can tell it's the only thing that seems to fail (which 
triggers everything else since they can no longer resolve anything).

When this issue happens, I can't communicate with unbound via 
unbound-control and it will never resolve anything. I can cleanly shut 
it down and start a new instance and it will behave exactly the same. 
The only solution I've found is to restart the VPS. I have another VPS 
from the same provider which is setup almost identically and it has 
never had this issue.

I've got debug logging on and the log file has dozens of requests per 
minute up until the issue occurred, then nothing until it received 
SIGTERM and shut down. The next time this happens (could be 
hours/days/weeks) is there anything else I can check that would explain 
why it does not appear to be even receiving the lookup requests?

Thanks,
--Will