Configure separate LAN for backup data transfer

Not sure what the purpose of 2nd LAN is when clients do not have access to it? 

Clients push backup data to media servers over the network. If they only have access to LAN 1, the backup data cannot travel over LAN 2.

Best to draw a network diagram of what it is that you want to accomplish. Ask your Network Admins for assistance.
Once you have a picture, we can help you with the NBU side of the configuration.

Thanks all for reply.

I configuring VADP backup via SAN connection to the storage. If I'm not wrong, NetBackup able to backup the data direct from the storage that connected to the media server through SAN connection (not SAN media server).

Yes all client can communicate to both master and media server via 1st LAN. But since NetBackup can access to the storage through the SAN connection is that means backup data is transfer via SAN connection only without through LAN connection? Because I think I will need configure all the storage that connected to the media server using the 2nd LAN to avoid backup data transfer using the 1st LAN.

when you configured the SAN transport for VADP backup, it does not matter what LAN is being used for connectivigy for Media and clients.. unless you want to use them for  Restores..

Storage is connected over the SAN not over the LAN noting to worry about it

only you need to care about it

Vcetner and ESXi hosts LAN commnication with the backup host and Master server 1st LAN or 2nd LAN

SAN connection to the Media server.

I agree with Nagalla.

If your config is correct, backups will be done over the SAN, not LAN.

Have a look at this excellent article:

(Netbackup) VMWare Backup over SAN

Thanks all for reply. Its look like 2nd LAN will be useless since only 1st LAN is use for communication between all nbu server and the client.

Required_Interface or Preferred_Network can be set on the Master and Media servers to allow NetBackup to choose the preferred network path. Also each secondary network should have it's own hostname in DNS. That hostname-bkp should be set in the client's bp.conf or registry as a SERVER entry. 

Once completed always verify these entries with bptestbpcd, ping, traceroute, nbdna, etc. Also run test backups. 

There are Tech docs on these two settings and this is also covered in the NetBackup Administrator's Guide vol 2. Also check out the Port Usage Guide.

NetBackup is a beast and will use every last drop of bandwidth and resources available.  Once the reconfiguration is completed. There will be more bandwidth to accomplish the backups and improve performance. Also this will allow production to work as intended. 

Thanks Scott. I just discovered this option.

Not actually sure why you need Required_Interface or Preferred_Network when it is clear from your previous posts that the Clients do not have access to LAN 2 and that VM backups will happen via the SAN ??