When I said re-init nisserver1, I just meant re-init the NIS environment on it. If you clear out the old maps in /var/yp/binding/DOMAIN_NAME (DOMAIN_NAME = Your NIS domain) directory on nisserver1 and run ypinit -s MASTER_SERVER_NAME where MASTER_SERVER_NAME is the name of the NIS master configured in the NIS maps. This will set the machine up as a new NIS slave server with a fresh copy of the maps from the NIS master. You have to remove the old binding dir before ypinit -s will run for a re-init.

If you don't want to re-init NIS on nisserver1, then depending on which version of UNIX you are running, it is possible to specify which NIS server to bind to. For instance, on Solaris you run ypinit -c and specify a search order the NIS servers for each client. This creates a ypservers file /var/yp/binding/DOMAIN_NAME where DOMAIN_NAME is the NIS domain name. You can edit this file to add/delete/modify NIS servers. If you remove the file completely, the ypbind daemon starts as a broadcast daemon by default.

This behaviour for NIS on most flavors of UNIX I've worked on. If for some reason the flavor of UNIX you are using doesn't support ypinit -c (SCO for instance), you must start ypbind with the -ypsetme flag and use ypset to manually assign an NIS server.

If you tell me what UNIX OS you're running, I can give you specific instructions if you need them.