Issue with DNS and Exchange When Primary DNS Has Shutdown

[Misan]

Hi guys - I have a 2 DC network, with the primary running Windows 2008 R2 with DNS installed and the secondary Windows 2008 Server.

If the R2 DC is shutdown Exchange 2003 services won't start and logins take up to 5 minutes. DNS resolution works fine for clients whilst web browsing. I've had a look around at it appears that the issue stems from not using AD integrated zones on the 2008 Server.

However, If i look at the forward lookup zone on the seconday DNS server, the option for 'Replication, Active Directory Integrated Zone' is greyed out. Couple of questions really.

1. Does it sound like the issue stems from not using AD integrated zones on the secondary DNS?
2. If so, would i be fine simply deleting both forward and reverse lookup zones on the secondary DC and re-creating them as AD integrated?

I should mention that both DC's have their own IP addresses set as their primary DNS.
Both DC's are GC's
The 2008 R2 server holds the FSMO roles.
Replication appears to be working fine according to the event logs (as long as the 2008 R2 DC is on)

Hope someone can help

Cheers

 

[Misan]

Hi guys - Managed to sort the issue now (well, as far as user logins go and general DNS issues) by setting my primary DNS zones to AD Integrated and by deleting both forward and reverse lookup zones on the secondary DNS and then forcing replication.

This seems to sort out DNS issues when the primary DC is shutdown. The Exchange issue seems to stem from what Burnsey mentioned with respect to looking at the primary DC for GC stuff.. so I'm gonna do some digging in the technet forums to see if theres a fix.

Many thanks for your replies