DP error while firing backup to Storeonce device

Hi,

We have DP 9.04 and HP StoreOnce 4500 Backup when we are firing backup from Windows 2008 Cell manager for one of our hpux client v3 we are egting below error :

 

Total Size ......... 0.00 KB

[Critical] From: BDA-NET@infapp1 "/e_commerce" Time: 9/29/2015 1:32:30 PM
Cannot connect to Media Agent on system nabard_bkp, port 5006 (IPC Cannot Connect
System error: [238] Connection timed out
) => aborting.

 

Only observed for LAN clients , SAN is fine.

Quite confused with forum answers regarding fire-wall entries , do i need to make them in firewall too ??

Why its needed ? We have already opened 9387 & 9388 for Storeonce TCP traffic ( in / out ) .