[nsd-users] NSD 4.0.1 unclean shutdown

[Anand Buddhdev]

I've noticed that when NSD shuts down, it can be a bit messy. Here's an
example:

[1390913907] nsd[22966]: warning: signal received, shutting down...
[1390913907] nsd[22966]: warning: rmdir /var/lib/nsd/nsd-xfr-1093
failed: Directory not empty
[1390913908] nsd[1093]: warning: rmdir /var/lib/nsd/nsd-xfr-1093 failed:
Directory not empty
[1390913932] nsd[23003]: info: zone 96.147.in-addr.arpa. received update
to serial 2014012801 at 2014-01-28T12:58:23 from 193.0.0.198 TSIG
verified with key ripencc-20110222 of 1026966 bytes in 0.202617 seconds

Notice that processes 22966 and 1093 (1093 is the main process) both
tried to delete a directory which contained an incoming zone transfer,
and failed. This incoming zone transfer was being processed by process
23003.

When I killed 1093, it exited almost immediately, and did not wait for
any of its children. In particular 23003 continued running for 24 more
seconds, and only exited after applying the zone transfer to the database.

This is problematic, because when I killed 1093, and it exited, as far
as I was concerned, NSD was completely shut down, and I could restart
it, or do other housekeeping. But one NSD process was still running.
Additionally, that last process, after applying its zone transfer, did
not remove the directory /var/lib/nsd/nsd-xfr-1093, so that directory is
now hanging around.

Is there any reason the master process does not wait for its children to
finish before exiting?

Anand