NIS Problems Affecting One Client

If only one or two clients are experiencing symptoms that indicate NIS binding difficulty, the problems probably are on those clients. If many NIS clients are failing to bind properly, the problem probably exists on one or more of the NIS servers. See NIS Problems Affecting Many Clients.

ypbind Not Running on Client

One client has problems, but other clients on the same subnet are operating normally. On the problem client, run ls -l on a directory, such as /usr, that contains files owned by many users, including some not in the client /etc/passwd file. If the resulting display lists file owners who are not in the local /etc/passwd as numbers, rather than names, this indicates that NIS service is not working on the client.

These symptoms usually mean that the client ypbind process is not running. Verify whether the NIS client service is running.

client# svcs network/nis/client
STATE          STIME    FMRI
disabled       Sep_01   svc:/network/nis/client:default

If the client is disabled, log in as superuser, or assume an equivalent role, and start the NIS client service.

client# svcadm enable network/nis/client

Missing or Incorrect Domain Name

One client has problems, the other clients are operating normally, but ypbind is running on the problem client. The client might have an incorrectly set domain.

On the client, run the domainname command to see which domain name is set.

client7# domainname neverland.com

Compare the output with the actual domain name in /var/yp on the NIS master server. The actual NIS domain is shown as a subdirectory in the /var/yp directory.

Client7# ls /var/yp...
-rwxr-xr-x 1 root Makefile
drwxr-xr-x 2 root binding
drwx------ 2 root doc.com ...

If the domain name returned by running domainname on a machine is not the same as the server domain name listed as a directory in /var/yp, the domain name specified in the machine's /etc/defaultdomain file is incorrect. Log in as superuser or assume an equivalent role, and correct the client's domain name in the machine's /etc/defaultdomain file. This assures that the domain name is correct every time the machine boots. Now reboot the machine.

The domain name is case-sensitive.

Client Not Bound to Server

If your domain name is set correctly, ypbind is running, and commands still hang, then make sure that the client is bound to a server by running the ypwhich command. If you have just started ypbind, then run ypwhich several times (typically, the first one reports that the domain is not bound and the second succeeds normally).

No Server Available

If your domain name is set correctly, ypbind is running, and you get messages indicating that the client cannot communicate with a server, this might indicate a number of different problems:

• Does the client have a /var/yp/binding/domainname/ypservers file containing a list of servers to bind to? If not, run ypinit -c and specify in order of preference the servers that this client should bind to.

• If the client does have a /var/yp/binding/domainname/ypservers file, are there enough servers listed in it if one or two become unavailable? If not, add additional servers to the list by running ypinit -c.

• Do the servers listed in a clients ypservers file have entries in the /etc/hosts file? If not, add the servers to the NIS maps hosts input file and rebuild your maps by running yppinit -c or ypinit -s as described Working With NIS Maps.

• Is the /etc/nsswitch.conf file set up to consult the machine's local hosts file in addition to NIS? See Chapter 2, The Name Service Switch (Overview) for more information on the switch.

• Is the /etc/nsswitch.conf file set up to consult files first for services and rpc? See Chapter 2, The Name Service Switch (Overview) for more information on the switch.

ypwhich Displays Are Inconsistent

When you use ypwhich several times on the same client, the resulting display varies because the NIS server changes. This is normal. The binding of the NIS client to the NIS server changes over time when the network or the NIS servers are busy. Whenever possible, the network becomes stable at a point where all clients get acceptable response time from the NIS servers. As long as your client machine gets NIS service, it does not matter where the service comes from. For example, an NIS server machine can get its own NIS services from another NIS server on the network.

When Server Binding is Not Possible

In extreme cases where local server binding is not possible, use of the ypset command can temporarily allow binding to another server, if available, on another network or subnet. However, in order to use the -ypset option, ypbind must be started with either the -ypset or -ypsetme options. For more information, see the ypbind(1M) man page.

# /usr/lib/netsvc/yp/ypbind -ypset

For another method, see Binding to a Specific NIS Server.

For security reasons, the use of the -ypset and -ypsetme options should be limited to debugging purposes under controlled circumstances. Use of the -ypset and -ypsetme options can result in serious security breaches because while the daemons are running, anyone can alter server bindings causing trouble for others and permitting unauthorized access to sensitive data. If you must start ypbind with these options, once you have fixed the problem you should kill ypbind and restart it again without those options.

To restart ypbind, use the service management facility (SMF):

# svcadm enable -r svc:/network/nis/client:default

ypbind Crashes

If ypbind crashes almost immediately each time it is started, look for a problem in some other part of the system. Check for the presence of the rpcbind daemon by typing the following.

% ps -e | grep rpcbind

If rpcbind is not present or does not stay up or behaves strangely, consult your RPC documentation.

You might be able to communicate with rpcbind on the problematic client from a machine operating normally. From the functioning machine, type the following.

% rpcinfo client

If rpcbind on the problematic machine is fine, rpcinfo produces the following output.

program	version	netid	address	service	owner
...
100007	2	udp	0.0.0.0.2.219	ypbind	superuser
100007	1	udp	0.0.0.0.2.219	ypbind	superuser
100007	1	tcp	0.0.0.0.2.220	ypbind	superuser
100007	2	tcp	0.0.0.0.128.4	ypbind	superuser
100007	2	ticotsord	\000\000\020H	ypbind	superuser
100007	2	ticots	\000\000\020K	ypbind	superuser
...

Your machine will have different addresses. If the addresses are not displayed, ypbind has been unable to register its services. Reboot the machine and run rpcinfo again. If the ypbind processes are there and they change each time you try to restart the NIS service, reboot the system, even if the rpcbind daemon is running.