Multi-server considerations

When running GDBM in multi-server mode, the change log is shared by all of the LDAP servers in the same cross-system group. Each LDAP server must have an identical GDBM backend configured to avoid the possibility of not logging a change that should be logged (or the reverse). Note that each TDBM, LDBM, and CDBM backend must run in the same mode as GDBM. They must all run in multi-server mode or all not run in multi-server mode.