[NAME].1 [NAME] , Thank you both of you. The issue is resolved. Now I can send backup from the Data domain to the Tape library. The solution was, enabling the Fiber channel. From Networker--> go to Device -->then select devices --> then storage node --> then data domain disk --> click properties --> then configuration --> select Enable the fiber channel and hostname: hostname of the data domain. 
Hi All, I am new to Networker software. Recently I am maintaining it. As i am new in this, I have a query on backup and cloning. 1. We are taking File system backup over IP to the data domain box (client is a VMWare guest). Then we clone the backup from the Data domain to the ML3 Tape library. I have found that the speed is really slow from the data domain to the tape library (around 11mbps). But zoning is there with ML3 tape library and data domain box. How can we resolve this? It would be really helpful if someone could help us with this.
Networker backup clonning.