4.6. Lock Files

4.6. Lock Files

Each Directory Server instance contains a /var/lock/dirsrv/slapd-instance_name directory for storing lock-related files. The following is a sample listing of the locks directory contents. 

exports/ imports/ server/
Example 4.4. Lock Directory Contents

The lock mechanisms stored in the exports, imports, and server subdirectories prevent multiple, simultaneous operations from conflicting with each other. The lock mechanisms allow for one server instance to run at a time, with possible multiple export jobs. They also permit one ldif2db import operation at a time (not ldif2db.pl, because multiple ldif2db.pl operations can be run at any time) to the exclusion of all export and slapd server operations.

If there are error messages indicating that the lock table is out of available locks (for example, libdb: Lock table is out of available locks), double the value of the nsslapd-db-locks attribute in the cn=config,cn=ldbm database,cn=plugins,cn=config entry.

For example, if the current value is 10000, set it to 20000. If the problem persists, double the number again. To monitor the current and maximum number of locks, do a search on cn=database, cn=monitor, cn=ldbm database, cn=plugins, cn=config. For example: 

ldapsearch -h localhost -p 389 -D "cn=directory manager" -w password
     -b "cn=database,cn=monitor,cn=ldbm database, cn=plugins,cn=config" objectclass=* | grep -- -locks: )

For more information on using LDAP utilities, see the Directory Server Administration Guide.


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