DR BorderManager

We are trying to set up a BorderManager server to replace an existing
one in the event of a failure. Since authentication (Client Trust) is
not needed, we set up a server in it's own tree. We installed NetWare
using the same IP addresses as the existing BorderManager (keeping it
off the network). Added all the secondary IP Addresses, 1-to-1 NATs and
routing information. Next we installed BorderManager 3.8 and selected
HTTP and IP Packet Filtering Services. Patched to SP5 and verified
filters. Deleted the filters (in NWAdmin), cleared filters (filtsrv
-cf), unloaded filtsrv, copied the filters.cfg from the existing
BorderManager to the DR one and loaded via filtsrv migrate filters.

We then bounced the server to ensure everything was OK, checked the
filters (via filtcfg) and all the IP settings (via inetcfg). Then
unplugged the Private and Public cables for the existing BorderManager
and plugged the DR BorderManager cables in. HTTP proxy worked fine, but
GWIA (and the MTA) could not connect with the outside. I was able to
telnet to another GWIA (on port 25) so it would appear that outbound was
OK. We dropped the filters and GWIA started working. Since we couldn't
keep the DR BorderManager online for too long, we had limited
troubleshooting time. And came up with nothing... So back the the
original BorderManager and everything still works.

What did we miss???

Thanks,
Mark