If the servers are up and running, try to find a client machine behaving normally, and run the ypwhich command. If ypwhich does not respond, kill it. Then log in as root on the NIS server and check if the NIS ypbind process is running by entering:
# ps -e | grep yp |
Do not use the -f option with ps because this option attempts to translate user IDs to names which causes more name service lookups that may not succeed.
If either the ypbind or ypserv daemons are not running, kill them and then restart them by entering:
# /usr/lib/netsvc/yp/ypstop # /usr/lib/netsvc/yp/ypstart |
If both the ypserv and ypbind processes are running on the NIS server, type:
# ypwhich |
If ypwhich does not respond, ypserv has probably hung and should be restarted. While logged in as root on the server, kill ypserv and restart it by typing:
# /usr/lib/netsvc/yp/ypstop # /usr/lib/netsvc/yp/ypstart |