RPC Server Not Available- DNS Lookup problem

[J]

When I go to AD Sites and try to force replication b/n
the other DC's in AD, I get RPC Server Not Available
indicating a DNS Problem. I realize it's probably
related to earlier post. Any help re: situation above
and situation below would be greatly appreciated. Is DNS
now managed from AD Users& Computers instead of DNS Snap
in? How can I test/troubleshoot DNS in AD?

We were previously running mixed mode, after upgrading
all
servers to 2000, I switched "pdc" to native mode and the
other 2 DC's showed native mode.

We had DNS running on all 3. I had Standard Primary Zone
for our domain (company.com) on the former "pdc" and
Standard Secondary Zones for the other two DC's.

I changed the zone type from Standard Primary to Active
Directory Integrated on the "pdc" (it is the
infrastructure, pdc, and schema master) for both the
forward and reverse lookup zones. That worked fine.

When I went to the 2nd DNS Server which was running as
Standard Secondary Zone, I was able to swith the forward
lookup zone for our company.com to AD Integrated, but
when
I went to switch the REVERSE LOOKUP Zone, it would NOT
allow the zone type to be switched.

ON the 3rd DNS Server, I was not able to swtich either
forward or reverse lookup zone type from the STandard
Secondary.

The RPC Server service would not allow any replication
from the old "pdc", the one I switched to Active
Directory
integrated on both forward and reverse lookup zone.

Anyway, after rebooting to hopefully intiate replication
on all servers, I no long have our company.com on ANY DNS
Server and can not recreate it by right clicking. The
only knowledge base I saw re: this was related to SP1 and
SP2, we have SP4 on all machines.

How can I get our company.com to reappear in the DNS Snap-
in? What do I need to check?

 

[Lanwench [MVP - Exchange]]

Check the system clocks on all DCs to make sure there are no discrepancies.
I think even a 5 minute difference can lead to this error.

If you run net time /querysntp on all DCs, what do you see?

 

[Kevin D. Goodknecht [MVP]]

In

When I go to AD Sites and try to force replication b/n
the other DC's in AD, I get RPC Server Not Available
indicating a DNS Problem.

The first thing you should check any time you get RPC Server not available
is that you have all of these registry entries:
----- cut here ---------
REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\RPC\ClientProtocols]
"ncacn_np"="rpcrt4.dll"
"ncacn_ip_tcp"="rpcrt4.dll"
"ncadg_ip_udp"="rpcrt4.dll"
"ncacn_nb_tcp"="rpcrt4.dll"
"ncacn_http"="rpcrt4.dll"
----- cut here ---------

 

[j]

On the DC that was acting as our PDC and is current
infrastructure, pdc and "other" can't remember MASTER, I
get ntp2.usno.navy.mil comand completed successfully;

on the other 2 DC's where I had Secondary Zones setup for
DNS with our domain, I get, This computer is not
configured to use a specific sntp server, command
completed successfully.

Is it necessary to have Active Directory integrated DNS
for Active Directory to work? Ever since I tried to
change DNS Zones from Standard Primary and Standard
Secondary to Active Directory, our domain no longer
appears in DNS SNap-ins and log-ins are taking longer
than usual.

Thanks in advance.

 

[Guest]

it is already there in the reigistry. any other ideas??

-----Original Message-----
In

When I go to AD Sites and try to force replication b/n
the other DC's in AD, I get RPC Server Not Available
indicating a DNS Problem.

The first thing you should check any time you get RPC Server not available
is that you have all of these registry entries:
----- cut here ---------
REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\RPC\ClientProtocols
]
"ncacn_np"="rpcrt4.dll"
"ncacn_ip_tcp"="rpcrt4.dll"
"ncadg_ip_udp"="rpcrt4.dll"
"ncacn_nb_tcp"="rpcrt4.dll"
"ncacn_http"="rpcrt4.dll"
----- cut here ---------




.

 

[J]

it is already there in the reigistry. any other ideas??

In

When I go to AD Sites and try to force replication b/n
the other DC's in AD, I get RPC Server Not Available
indicating a DNS Problem.

The first thing you should check any time you get RPC Server not available
is that you have all of these registry entries:
----- cut here ---------
REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\RPC\ClientProtocols]
"ncacn_np"="rpcrt4.dll"
"ncacn_ip_tcp"="rpcrt4.dll"
"ncadg_ip_udp"="rpcrt4.dll"
"ncacn_nb_tcp"="rpcrt4.dll"
"ncacn_http"="rpcrt4.dll"
----- cut here ---------

 

[Ace Fekay [MVP]]

In

it is already there in the reigistry. any other ideas??

What errors do you have in your Event Viewer?

RPC errors can be due to a few things, besides the name resolution method
that Kevin mentioned, and the time skew 5 minute tolerance that Kerberos
requires, it can also be due to NAT, MTU alterations (such if using ADSL
between remote locations). I've seen this happen when one of my clients
upgraded their firmware on one of their Sonic Walls they were using for
VPNs/NAT. The firmware altered the MTU settings, then everything went south
after that. About 3 weeks later, they lost all their zone data because it
expired. I finally nailed it down after 2 days hunting thru their system
when one of the guys said, "Oh, by the way, we just updated our firmware
blah blah blah....", etc. So this would depend on your network topology and
any other changes that were made. Chaning to Native mode won't do that.

So... can we see an ipconfig /all from your DCs please? Also, can you
describe your topology? Things such as; remote locations, what sort of line
to the Internet, what type of connectivity devices are you using, are you
using NAT, are the locations VPN'd and what are you using for the VPNs, etc.

Thanks!


--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS-IS" with no warranties and confers no
rights.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory

HAM AND EGGS: A day's work for a chicken; A lifetime commitment for a
pig. --
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