I am having a problem that really bothers me.
Sometimes, I have to do
killall -9 named
and then restart it because my domain names stop working. What can be causing this and what can I do to fix it?

I faced the same problem.
BTW, are you running Plesk ?

I used a turnaround by using a cron-job referred by melovic on this forum. It is keeping things under control by monitoring my services at every 5 mins interval.

If you scroll down this forum itself, you will find the post.

Abhishek

Well, its not clear of what your problem is,

what do you mean it just stops? if your running more than one domain does it stop for all of them or just that one? and also, "killall -9 named" doesn't seem too good I suggest doing "ndc restart", if you just want to do the lazy-man's way of fixing the problem, you could setup a crontab to restart it every 10 minutes or so.

eg:

crontab -e
(hit i for insert if your not familiar with vi)
0,10,20,30,40,50 * * * * /usr/sbin/ndc restart >/dev/null 2>&1
(hit ESC + :wq! to save)

if you need anymore help, let me know.