While working on my DiskCompare.com website I had a weird problem with daemontools. The Django process I had running under daemontools became unresponsive, it wouldn't shutdown normally with
svc -d, and after
kill -9 and restarting, it still wouldn't respond - it just seemed hung up or frozen. No messages in
/var/log/messages, but running the service manually outside of daemontools worked fine. What the heck?
I had the service also setup to run
multilog, and it turns out that I had mistakenly changed the ownership of the log directory it was supposed to be writing to. My guess is that it was the
multilog process that was really hung up, since it couldn't write to the files it wanted to, and that my Django processes were then blocked because the pipe between them and multilog was full.
Simply correcting the permissions of the
log directory cleared the jam and things took off again. So if you're seeing strange behavior with
daemontools, that's one area to check out.