With Red Hat Enterprise Linux, OpenLDAP uses Sleepycat Software's Berkeley DB system as its on-disk storage format for directories. Earlier versions of OpenLDAP used GNU Database Manager (gdbm). For this reason, before upgrading an LDAP implementation to Red Hat Enterprise Linux 4.5.0, original LDAP data should first be exported before the upgrade, and then reimported afterwards. This can be achieved by performing the following steps:
Before upgrading the operating system, run the command
/usr/sbin/slapcat -l ldif-output. This outputs an LDIF file called
ldif-output containing the entries from the LDAP directory.
Upgrade the operating system, being careful not to reformat the partition containing the LDIF file.
Re-import the LDAP directory to the upgraded Berkeley DB format by executing the command
/usr/sbin/slapadd -l ldif-output.