Data Domain DD2500 blocking other data domain

Hi All,

I've lost connectivity from one Data Domain to another one which is in a different location. When I log into the one data domain I am unable to ping the other one at the different location. I am able to ping app servers on the same network and at the different location on the Data Domain. Is there some feature that the Data domain has which can block another Data Domain for access?

I'm still trying to figure out the firewall rules but we generally don't block any traffic on a site to site VPN.

Thanks