I think I caught the error. The "schemachecking" was disable in "syncrepl" in slapd.conf That's why it was not displaying any error in case of missing mandatory parameter.
And as you said, we should not modify standard schema. Then what can I do if I want to add some "objectClass" and "attributes" in schema? Is there any way out to do this without changing the standard schema?
Thanks, Gurjot Kaur "DISCLAIMER: This message is proprietary to Aricent and is intended solely for the use of the individual to whom it is addressed. It may contain privileged or confidential information and should not be circulated or used for any purpose other than for what it is intended. If you have received this message in error, please notify the originator immediately. If you are not the intended recipient, you are notified that you are strictly prohibited from using, copying, altering, or disclosing the contents of this message. Aricent accepts no responsibility for loss or damage arising from the use of the information transmitted by this email including damage from virus."