The above parameters are timeouts for the ldap bind, modify, add, and delete operations, respectively. They should generally be left at their default values.
The above parameters set the timeout for the LDAP search operation, and request a server-side search time limit, respectively. Since the nisplusLDAPsearchTimeLimit will control how much time the LDAP server spends on the search request, make sure that nisplusLDAPsearchTimeLimit is not smaller than nisplusLDAPsearchTimeout. Depending on the performance of the NIS+ server, the LDAP server, and the connection between them, you might have to increase the search limits from the default values. Watch for timeout syslog messages from rpc.nisd as a clue to making these values larger.
The above parameter requests a limit on the amount of LDAP data returned for an LDAP search request. The default is to ask for no limitation. This is a server side limit. The LDAP server might impose restrictions on the maximum, and these restrictions might be tied to the proxy user (bind DN) used. Make sure that the LDAP server allows the rpc.nisd to transfer enough data to account for the largest container (depending on the site, often the container used for passwd.org_dir, mail_aliases.org_dir, or netgroup.org_dir). Consult your LDAP server documentation for more information.
The above parameter defines the action to be taken when an LDAP operation results in a referral to another LDAP server. The default is to not follow referrals. Enable follow referrals if you want or need referrals to be honored. Keep in mind that while referrals are convenient, they can also slow down operations by making the rpc.nisd talk to multiple LDAP servers for each request. The rpc.nisd should generally be pointed directly to an LDAP server that can handle all LDAP requests that the rpc.nisd might make.