PDC down - Strange Behaviour

I have 2 domain controllers. Dc1 has PDC Emulator, RID Master and
Infrastructure.

Dc2 has the Schema Master and Domain Naming Master roles.

yesterday for some reason Dc1 went down. We lost our internet connectivity
as a result - for some reason ISA 2004 was not able to use DC2 and maintain
internet connectivity.

Also I was not able to connect to any for the servers via RDP - I just got
the error that the domain is not available.

However Dc2 is up and running?

Is this normal behaviour?

thanks

Marcin
Fri May 09 08:40:13 PDT 2008

What's your DNS infrastructure?

"Vishal" <Vishal@discussions.microsoft.com> wrote in message
news:5F7F0609-45A1-437D-B508-42C346E4584A@microsoft.com...
>I have 2 domain controllers. Dc1 has PDC Emulator, RID Master and
> Infrastructure.
>
> Dc2 has the Schema Master and Domain Naming Master roles.
>
> yesterday for some reason Dc1 went down. We lost our internet connectivity
> as a result - for some reason ISA 2004 was not able to use DC2 and
> maintain
> internet connectivity.
>
> Also I was not able to connect to any for the servers via RDP - I just got
> the error that the domain is not available.
>
> However Dc2 is up and running?
>
> Is this normal behaviour?
>
> thanks

Danny
Fri May 09 08:43:30 PDT 2008

> Is this normal behaviour?
>
> thanks

Kind of.......

Sounds like your DC1 is the server all your clients are pointed to for DNS
and when it goes down they don't get DNS resolution. They say that you
should have a second DNS server listed on the clients and they will use that
when the first DNS server is unavailable. But in my experience when the
Primary DNS server is down I've always had to manually tell the clients to
use the alternate DNS server by setting it as the primary DNS server.

hth
DDS

"Vishal" <Vishal@discussions.microsoft.com> wrote in message
news:5F7F0609-45A1-437D-B508-42C346E4584A@microsoft.com...
>I have 2 domain controllers. Dc1 has PDC Emulator, RID Master and
> Infrastructure.
>
> Dc2 has the Schema Master and Domain Naming Master roles.
>
> yesterday for some reason Dc1 went down. We lost our internet connectivity
> as a result - for some reason ISA 2004 was not able to use DC2 and
> maintain
> internet connectivity.
>
> Also I was not able to connect to any for the servers via RDP - I just got
> the error that the domain is not available.
>
> However Dc2 is up and running?
>
> Is this normal behaviour?
>
> thanks

Herb
Fri May 09 23:15:11 PDT 2008


"Vishal" <Vishal@discussions.microsoft.com> wrote in message
news:5F7F0609-45A1-437D-B508-42C346E4584A@microsoft.com...
>I have 2 domain controllers. Dc1 has PDC Emulator, RID Master and
> Infrastructure.
>
> Dc2 has the Schema Master and Domain Naming Master roles.
>
> yesterday for some reason Dc1 went down. We lost our internet connectivity
> as a result - for some reason ISA 2004 was not able to use DC2 and
> maintain
> internet connectivity.
>
> Also I was not able to connect to any for the servers via RDP - I just got
> the error that the domain is not available.
>
> However Dc2 is up and running?
>
> Is this normal behaviour?

Normal? No. Common? Yes.

It is almost always due to incorrect DNS setup.

Both DCs should (in the simplest setup) be DNS servers and GCs (in
case you are in Native+ mode) -- all "DNS clients" should point to
BOTH of them in their NIC->IP properties.

"DNS Clients" include all servers even the DNS servers and DCs
themselves.