Red Hat Directory Server 8.0 Administrator's Guide

1
For information on stopping the server on platforms other than Red Hat Enterprise Linux, see Section 3, “Starting and
Stopping Servers”.
2
The LDAP tools referenced in this guide are Mozilla LDAP, installed with Directory Server in the
/usr/lib/mozldap directory on Red Hat Enterprise Linux 5 i386; directories for other platforms are listed in
Section 2, “LDAP Tool Locations”. However, Red Hat Enterprise Linux systems also include LDAP tools from
OpenLDAP. It is possible to use the OpenLDAP commands as shown in the examples, but you must use the -x
argument to disable SASL and allow simple authentication.
themselves. Because the purpose of the transaction log is to aid in the recovery of a directory
database that was shut down abnormally, it is a good idea to store the database transaction log
on a different disk from the one containing the directory database. Storing the database
transaction log on a separate physical disk may also improve directory performance.
To change the location of the database transaction logfile, use the following procedure:
1. Stop the Directory Server
1
.
service dirsrv stop instance_name
2.
Use the ldapmodify
2
command-line utility to add the nsslapd-db-logdirectory attribute to
the cn=config,cn=ldbm database,cn=plugins,cn=config entry. Provide the full path to
the log directory in the attribute.
For information on the nsslapd-db-logdirectory attribute syntax, see the Directory Server
Configuration, Command, and File Reference. For instructions on using ldapmodify, see
Section 2.4, “Adding and Modifying Entries Using ldapmodify”.
3. Restart Directory Server.
service dirsrv start instance_name
2.4. Changing the Database Checkpoint Interval
At regular intervals, the Directory Server writes operations logged in the transaction log to the
disk and logs a checkpoint entry in the database transaction log. By indicating which changes
have already been written to the directory, checkpoint entries indicate where to begin recovery
from the transaction log, thus speeding up the recovery process.
By default, the Directory Server is set up to send a checkpoint entry to the database transaction
log every 60 seconds. Increasing the checkpoint interval may increase the performance of
directory write operations. However, increasing the checkpoint interval may also increase the
amount of time required to recover directory databases after a disorderly shutdown and require
more disk space due to large database transaction log files. Therefore, only modify this attribute
if you are familiar with database optimization and can fully assess the effect of the change.
To modify the checkpoint interval while the server is running, use the ldapmodify
2
command-line utility to add the nsslapd-db-checkpoint-interval attribute to the
cn=config,cn=ldbm database,cn=plugins,cn=config entry.
For more information on the syntax of the nsslapd-db-checkpoint-interval attribute, refer to
the Directory Server Configuration, Command, and File Reference. For instructions on using
ldapmodify, see Section 2.4, “Adding and Modifying Entries Using ldapmodify”.
Changing the Database Checkpoint Interval
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