The following option allows you to undo (roll back) the changes made to the LDAP directory if an error occurs during the migration process:
-u UndoFile directs commdirmig to create a log in LDIF format that can be applied to undo the migration. The log entries are saved in the UndoFile you specify.
If an error occurs during the migration, you can use the ldapmodify tool with the Undo log to roll back all the changes made by commdirmig. This step returns the LDAP directory to the state it was in before the migration began.
By default, commdirmig creates an Undo file.
By default, the UndoFile is named commdirmig.undo.ldif.