NOTE:

Custom schema files should not be numerically or alphabetically higher than 99user.ldif or the server could experience problems.

After creating custom schema files, there are two ways for the schema changes to be distributed among all servers:

•Manually copy these custom schema files to the instance's schema directory,

/etc/opt/dirsrv/slapd-instance_name/schema. To load the schema, restart the server or reload the schema dynamically by running the schema-reload.plscript.

•Modify the schema on the server with an LDAP client such as the Directory Server Console or ldapmodify.

•If the server is replicated, then allow the replication process to copy the schema information to each of the consumer servers.

With replication, all the replicated schema elements are copied into the consumer servers' 99user.ldif file. To keep the schema in a custom schema file, like 90example_schema.ldif, the file has to be copied over to the consumer server manually. Replication does not copy schema files.

If these custom schema files are not copied to all the servers, the schema information are only replicated to the replica (consumer server) when changes are made to the schema on the supplier server using an LDAP client such as the Directory Server Console or ldapmodify.

When the schema definitions are replicated to a consumer server where they do not already exist, they are stored in the 99user.ldif file. The directory does not track where schema definitions are stored. Storing schema elements in the 99user.ldif file of consumers does not create a problem as long as the schema is maintained on the supplier server only.

If the custom schema files are copied to each server, changes to the schema files must be copied again to each server. If the files are not copied over again, it is possible the changes will be replicated and stored in the 99user.ldif file on the consumer. Having the changes in the 99user.ldif file may make schema management difficult, as some attributes will appear in two separate schema files on a consumer, once in the original custom schema file copied from the supplier and again in the 99user.ldif file after replication.

For more information about replicating schema, see “Schema replication”.

3.4.8 Custom schema best practices

When using schema files, be sure to create schema which will be compatible and easy to manage.

3.4.8.1 Naming schema files

When naming custom schema files, use the following naming format:

[00-99]yourName.ldif

Name custom schema files lower (numerically and alphabetically) than 99user.ldif. This lets Directory Server write to 99user.ldif, both through LDAP tools and the Directory Server Console.

The 99user.ldif file contains attributes with an X-ORIGINvalue of 'user defined'; however, the Directory Server writes all 'user defined' schema elements to the highest named file, numerically then alphabetically. If there is a schema file called 99zzz.ldif, the next time the schema is updated (either through LDAP command-line tools or the Directory Server Console), all the attributes with an X-ORIGINvalue of 'user defined' are written to 99zzz.ldif. The result is two LDIF files that contain duplicate information, and some information in the 99zzz.ldif file might be erased.

3.4 Customizing the schema

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