Hi,
I have configured ISP redundancy (for Failover only) with two ISPs.I'm confused about DNS resolution, here are my configurations:
TMG's Internal interface is set to internal primary and secondary DNS(AD) servers and both ISPs External interfaces are without DNS entered, empty! Metric 1 is on primary ISP interface and Metric 2 is on secondary ISP interface.
I have set OpenDNS servers (208.67.222.222 & 208.67.220.220) as forwarders on Internal DNS servers for public name resolution. And these DNS/AD servers are also behind this TMG (as secureNAT client). I am not using any of ISPs DNS because
using opendns for web filtering also.
Now my question is, do I also need to add static persistent route for DNS ips on TMG server when TMG's only internal interface is configured to use internal DNS?. Am i missing something? Please guide.
Thanks
Here is route print:
IPv4 Route Table
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 222.252.189.129 222.252.189.133 257 (Primary ISP)
0.0.0.0 0.0.0.0 192.168.1.1 192.168.1.4
258 (Secondary ISP)
.
.
===========================================================================
Persistent Routes:
Network Address Netmask Gateway Address Metric
0.0.0.0 0.0.0.0 222.252.189.129 Default (Primary ISP)
0.0.0.0 0.0.0.0 192.168.1.1 Default (Secondary ISP)
===========================================================================
IPv6 Route Table
===========================================================================
Active Routes:
If Metric Network Destination Gateway
1 306 ::1/128 On-link
1 306 ff00::/8 On-link
===========================================================================
Persistent Routes:
None