NIS Consistent configuration across the network

Why NIS? Primary reason is to provide same user configuration across the network Users go any machine and log in with the same password NOT a means of mounting files… that is NFS

Problem Workstation User changes Password

Problem Workstation User tries to login w/new password FAILURE!

Solution: Centralized management Workstation User changes Password NIS Server Stored on server

Solution: Centralized management Workstation NIS Server Ask server User tries to login w/new password Login succeeds SUCCESS!

OK, but is that all? NO. It’s just the most important function. More generally it allows centralization of many configuration parameters. Providing a server allows for storing the info in a single place w/ single copy. Must tell server what to share Must tell clients what to ask Understanding NIS requires knowing what it handles and what it doesn’t handle!

Who Can See It? Originally on a network segment Typically local Servers can be hard-coded or broadcast Security issues for –Broadcasting –Passwords for logging in Used by machines in the NIS domain –Not the same as a DNS domain but could have the same name

What else does it handle? Users, passwords,groups Mail aliases Host name/ip mapping like dns Boot parameters Printer definitions And others You can pick and choose which to provide

How are these functions similar? user encrypted password hostname ip address Both are simply mapping functions!

Main Components A server and its configuration –ypserv –yp.conf Client configuration –ypbind –nsswitch.conf Rpc portmapper running A domain defined Database files Option slave servers for redundancy

Setting up the server Make sure “rpc” is running ypserv (likely) – rpcinfo -u localhost ypserv –It will report versions running Generate the database files –/usr/lib/yp/ypinit -m Update as necessary by –Changing files –In /var/yp, run “make” If using network passwords, run rpc.yppasswd

Generating database files Can be tricky Each separate function should be addressed as the nuances are different. E.g. “dns’ function is used for NIS domain but regular DNS must be available for the outside world E.g. “password”s can be served some locally and some centrally

Setting up the client Define the location of server in /etc/yp.conf Use “domainname” to set machine domain –Same as in server Run rpcinfo -p localhost looking for ypbind and portmapper Create /var/yp directory if necessary Modify nsswitch.conf to use the nis service