I'm hoping someone can give some insight into this issue I have been having.
I have migrated our Internal ISA Server 2006 Server to Hyper-V on a new server.
What's been done so far:
1) Export the ISA config from old server
2 Install Windows OS and ISA Server 2006
3) Disconnect old ISA Server from network
4) Give new ISA Server the old ISA Server IP address
5) Import the ISA configuration from old server to new
6) Check configuration
7) Import Exchange RPC Certificates
8) Check ISA Logs make sure all is clear.
After all of the above I connect the ISA Server check all my access internal and external all works fine...
Then... after a few hours ISA starts dropping DNS queries for ex:
I would ping www.google.co.za
from my workstation and it doesn't resolve (it did before)
Ping is allowed in the firewall rules and the required DNS rules exist as they were there on the original server.
Our DNS on the DC's are set to forward any external DNS queries to a forwarder (in this case the ISA Server) (With the same IP I granted to the new ISA Server)
Like for like when I check everything it's all the same(same IP's same configuration rules, same ISA version, same SP version)
Any idea why after a few hours this would occur?
I put the old box back and my internal to external DNS queries works 100% again ( I get a reply when pinging www.google.co.za
I haven't really looked into the edge firewall (ISA 2004) too much as I can't see how it could contribute to this issue (no names are specified and all the rules are done through IP to IP)
You're help is much appreciated.