7.13. Adjusting the replication release timeout
An IdM replica is exclusively locked during a replication session with another replica. In some environments, a replica is locked for a long time due to large updates or network congestion, which increases replication latency.
You can release a replica after a fixed amount of time by adjusting the repl-release-timeout parameter. Red Hat recommends setting this value between 30 and 120:
- If the value is set too low, replicas are constantly reacquiring one another and replicas are not able to send larger updates.
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A longer timeout can improve high-traffic situations where it is best if a server exclusively accesses a replica for longer amounts of time, but a value higher than
120seconds slows down replication.
| Default value |
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| Valid range |
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| Recommended range |
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Prerequisites
- The LDAP Directory Manager password
Procedure
Display the database suffixes and their corresponding back ends.
[root@server ~]# dsconf -D "cn=Directory Manager" ldap://<server_fqdn> backend suffix list cn=changelog (changelog) dc=example,dc=com (userroot) o=ipaca (ipaca)This command displays the names of the back end databases next to their suffix. Use the suffix name in the next step.
Modify the value of the
repl-release-timeoutattribute for the main userroot database. This example increases the value to90seconds.[root@server ~]# dsconf -D "cn=Directory Manager" ldap://<server_fqdn> replication set --suffix="dc=example,dc=com" --repl-release-timeout=90Authenticate as the Directory Manager to make the configuration change.
Enter password for cn=Directory Manager on ldap://server.example.com: Successfully replaced "repl-release-timeout"Optional: If your IdM environment uses the IdM Certificate Authority (CA), you can modify the value of the
repl-release-timeoutattribute for the CA database. This example increases the value to90seconds.[root@server ~]# dsconf -D "cn=Directory Manager" ldap://<server_fqdn> replication set *--suffix="o=ipaca" --repl-release-timeout=90* Enter password for cn=Directory Manager on ldap://server.example.com: Successfully replaced "repl-release-timeout"Restart the Directory Server.
[root@server ~]# systemctl restart dirsrv.target-
Monitor the IdM Directory Server’s performance. If it does not improve, repeat this procedure and adjust
repl-release-timeoutto a different value, or back to the default of60seconds.
Verification
Display the value of the
nsds5ReplicaReleaseTimeoutattribute and verify it has been set to your desired value.[root@server ~]# ldapsearch -D "cn=Directory Manager" -w <directory_manager_password> -b "cn=replica,cn=dc\3Dexample\2Cdc\3Dcom,cn=mapping tree,cn=config" | grep nsds5ReplicaReleaseTimeout nsds5ReplicaReleaseTimeout: 90
The Distinguished Name of the suffix in this example is dc=example,dc=com, but the equals sign (=) and comma (,) must be escaped in the ldapsearch command.
Convert the suffix DN to cn=dc\3Dexample\2Cdc\3Dcom with the following escape characters:
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\3Dreplacing= -
\2Creplacing,