[j-nsp] issue with FW SA

[Harsh Bajaj]

HI

I have two firewalls- ISG2000 connected over WAN link on site 1 and site 2 2. We have policy configured with specific source/dest and service as FTP action as vpn tunnel between two sites
3. FTP connection usually initiated from site 1 to reach site2 
4. some times what happened is traffic stop working & if you login to firewall you see SA for that policy goes down .
5. problem get resolved if you initaite traffic from site 2 in place of site1.
6. Everything start working

Any suggestion?

Regards

Harsh