Server User Manual

cn=changelog5
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2.3.2. cn=changelog5
Multi-master replication changelog configuration entries are stored under the cn=changelog5 entry.
The changelog behaves much like a database, and it has many of attributes also used by the ldbm
databases.
The primary cache-related memory attribute, nsslapd-cachememsize, has a default value of
10485760 bytes, which is 10 MB. This parameter is tuned for a single backend replicated to a single
consumer.
When more backends are replicated or when one backend is replicated to more than one consumer,
tune the nsslapd-cachememsize so that its value is 5000000 times the number of replication
agreements initiated from the server (5000000 * no_of_repl_agreements).
The relationship between the values assigned to the nsslapd-dbcachesize and nsslapd-
cachememsize parameters should be the same as the relationship that is described in the database
tuning section.
The cn=changelog5,cn=config entry is an instance of the extensibleObject object class.
NOTE
Two different types of changelogs are maintained by Directory Server. The first
type, which is stored here and referred to as the changelog, is used by multi-
master replication; the second changelog, which is actually a plug-in and referred
to as the retro changelog, is for compatibility with some legacy applications. See
Section 3.1.29, “Retro Changelog Plug-in” for further information about the Retro
Changelog Plug-in.
2.3.2.1. nsslapd-changelogdir
This required attribute specifies the name of the directory in which the changelog database is created.
Whenever a changelog configuration entry is created, it must contain a valid directory; otherwise,
the operation is rejected. The GUI proposes by default that this database be stored in /var/lib/
dirsrv/slapd-instance_name/changelogdb.
WARNING
If the cn=changelog5 entry is removed, the directory specified in the nsslapd-
changelogdir parameter, including any subdirectories, are removed, with all of
their contents.
NOTE
For performance reasons, store this database on a different physical disk.
The server has to be restarted for changes to this attribute to go into effect.
Parameter Description
Entry DN cn=changelog5,cn=config