I use Fabric Manager SA 3.2(2c) on Windows XP to administer my local 9509. I'm trying to discover a 9513 fabric at our DR site - here's what happens:
1) login to FM
2) Goto Control Panel Fabrics tab, click Discover
3) Enter IP of 9513 for Seed Switch
4) Enter my account User Name and Password
5) Click Discover
Several seconds later:
ERROR Discover New Fabric
I can SSH into the 9513 with my account and also contact it with my web browser.
Is there a firewall/ACL in between sites that has blocked SNMP traffic? Its not uncommon sometimes and lots of organisations allow ssh and http but have real concerns with SNMP and will often block the ports. Universities in particular have to be extra vigilent just because of their students...
An easy way to test it is to put FM on a system at the remote site and try to discover the switch there. Is there another SNMP enabled device in the DR site you (or the network people) can try an snmpget/snmpwalk on?