SUMMARY: ypbind: NIS server not responding for domain

Dear sun-managers,

regarding my YP question I got several responses, but none of them 
did help me with my problem. Since most of them should be helpful in
other cases, I'll summarize them below anyway.

In our case the problem turned out to be a remote YP slave-server which
updates its maps every 30 minutes via a cron job. The leased line to that
server has problems since yesterday (in one direction it has a large
packet loss). The unsuccessful tries to transfer the maps seem to bog the
master server down. Since stopping these jobs, my YP master is fine again.
Seems as if the master ypserv gets locked by these transfers.

Here are the other suggestions I received by mail:

- check disk space in /var (we had plenty)
- install the recent patches, especially 105403-04 (we did, also
  108890-01 and 108893-01, didn't help. The only difference is that
  ypbind now writes "unable to set maximum RPC record size" upon
  startup, but otherwise works)
- use ypwhich to determine to which master ypbind binds (we did this
  before posting. The master was bound to itself, as it should be.
  Things got better when we used ypset to bind the master's ypbind
  to one of the slave servers. So I knew the problem is ypserv, not ypbind)
- check the usual 100Mbit/FDX/autonegotiation stuff for the network
  card (all is fine here. The network interface is not part of our problem
  since the ypserv and ypbind are on the same machine)
- check that the maps are correct (they were, otherwise I would have had
  problems on the slaves as well)
- run a script which automatically restarts the whole yp stuff, when the 
  binding fails (ugh...)

Thanks to Mark Gosselin, Nabeel Ahmed, Richard J. Buchman, John S. McNab,
Bertrand Hutin, David Foster and Suresh Rajagopalan for their suggestions.

Jan-Olaf

Original Question:

today we are observing some strange behaviour of ypbind on our YP
master server:

Every once in a while, ypbind logs "NIS server not responding for
domain XXX" and everything which tries to resolve something via YP
hangs. Sometimes it comes back with "NIS server for domain "XXX" OK"
after a couple of minutes, sometimes it needs a 'ypstop;ypstart'
to get things running again.

ypserv and ypbind are running on the same machine, which is also the YP
master for domain XXX. All other ypbinds which are bound to slave servers
are fine.

Does anyone have an idea what could cause this problem and what to do to
fix it? I have one other machine where I had the same problem but since
it occured only at night and only once a month I decided to ignore it.
Both machines are running Solaris 2.6.
-- 
Jan-Olaf Droese         | Lahmeyer International GmbH
email: zdjod@lif.de     | Friedberger Strae 173
phone: +49-6101-55-1611 | 61118 Bad Vilbel
fax:   +49-6101-55-1623 | Germany