Declaring a new schema epoch

  • 7001617
  • 10-Oct-2008
  • 27-Apr-2012


Novell eDirectory
Novell Directory Services
Novell Operating Systems


Declaring a new schema epoch
Corrupt schema in tree
Schema not properly extended
It is VITAL that all servers are on-line and communication is established between all servers.
When declaring a new schema epoch, the master replica of the ROOT partition is contacted and illegal time stamps are repaired.  All other servers in the tree will receive a new copy of the schema including the repaired time stamps. If the receiving server contains a schema definition that was not in the schema received in the new epoch, objects and attributes that use the old schema will be changed to the Unknown object class or attribute.
Declaring a schema epoch will increase network utilization significantly in large environments.  For this reason, it is best performed after normal working hours.  

***NOTE- Use EXTREME caution when using this option. If any schema is bad then declaring a new schema epoch will force the incorrect schema out to the rest of the tree.***

IMPORTANT- Prior to declaring a schema epoch perform a DS Health Check TID #3564075 - NDS Health Check Procedures - Cross Platform 
It is always wise to create backups of the database on each server. This can be done by running DSREPAIR -RC or by loading DSREPAIR -A | Advanced options menu | NDS archive options | Create NDS archive.


Procedure- From the Master or a Read-Write of the [ROOT] partition:

        2) Load DSREPAIR -A at the system console
        3) Go to "Advanced options menu" then go to "Global schema operations"
        4) Login as the Tree Administrator
        5) Select "Declare a New Epoch"
        6) A message will appear indicating success or any errors encountered while attempting to declare the schema epoch
        7) Verify the schema epoch has succeeded by a "schema epoch succeeded" and "All processed=yes" message in the directory services trace screen or by using a DS utility such as DSBROWSE to view the current schema epoch.  

For example, in DSBROWSE, Select "Schema Browse", Press F3 on "[Schema Root]","View Attributes", Select "Partition Creation Time","View Value Details".  The Modification Timestamp listed should be pretty close to when the Schema Epoch was declared.  "Press <ENTER> to display the attribute data in hex". The epoch number will be in the first byte of the hex display and the replica number is the second byte.  The replica number should be equal to the replica number for the Master of the [ROOT] partition.  To find the replica number of the Master of the [Root] see TID #10066774 - Looking up a replica number in DSBROWSE.NLM

Additional Information

Formerly known as TID# 10066252