WINS and BROWSER issues

[Brian]

I've got a mysterious problem with my Win2K servers. In
the middle of the night my PDC will show two error
messages in the system logs:

4102 (Wins)
The connection was aborted by the remote WINS. Remote
WINS may not be configured to replicate with the server.

8003 (MRxSmb)
The master browser has received a server announcement
from the computer BDC1 that believes that it is the
master browser for the domain..... The master browser is
stopping or an election is being forced.

The PDC is the master browser for the network segment.
It has WINS and DNS servers running on it. It is setup
as a push/pull partner with another WINS server (BDC2) on
the same domain but on a different subnet, separated by
Cisco 2524 routers. The second WINS server (BDC2) is
also a domain controller, acting as the master browser on
it's segment.

The 8003 MRxSmb error repeats itself every 72 minutes.

A few minutes after the 4102 WINS error on the PDC (which
only occurs the once) the same message appears on the
remote BDC2.

It's at about this time that the PDC gets "lost" from the
network and other servers cannot see it, even through
just the IP address. A reboot corrects the problem.

About 9 1/2 hours before this happens, for every 2 - 2
1/2 hours the BDC1 (another DC on the same segment as the
PDC) reports these two errors:

8021 BROWSER
The browser was unable to retrieve a list of servers from
the browser master \\PDC on the network..... The data is
in the error code.

8032 BROWSER
The browser service has failed to retrieve the backup
list too many times on transport.... The backup browser
is stopping.

It's hard to troubleshoot because I can't be here in the
middle of the night nor can I allow it to remain "lost"
for very long in the morning since the servers are all in
production and needed.

On BDC1 I've set the MaintainServerList registry entry to
Yes and IsDomainMaster to False, on PDC - Yes & True, on
BDC2 - Yes & False, on three other servers (non-DC's) on
the PDC's segment - Auto & False.

When the Browser service on BDC1 is restarted
then "browstat view" shows:
PDC {...PDC, MBR}
BDC1 {...BDC, BBR}
BDC2 {...BDC, MBR}
non-DC's {...SS, PBR}

Once the Browser service on BDC1 fails then "browstat
view" shows:
PDC {...PDC, MBR}
BDC1 {...BDC}
BDC2 {...BDC, MBR}
non-DC's {...SS, PBR, BBR}

Also, non of the servers are multi-homed and I've added
the following lines to my routers to disable UDP
forwarding:
no ip forward-protocol udp netbios-ns
no ip forward-protocol udp netbios-dgm

Like I said before, the biggest effect of this problem is
that the PDC gets "lost" from the network.

Any ideas?
Thanks

 

[Brian]

Sorry, I should have said that the BDC1 also loose's it's
network connection. A reboot of just the PDC fixes the
problem, temporarily.

 

[Brian]

Well, I may have found the problem. The WINS/DNS server
on remote subnet #2 was pointing to the WINS/DNS server
on subnet #1 in it's NIC config. Sounds too simple to be
true, but this may have been it all along - don't know,
time will tell. I'm going to try restarting the browser
service on BDC1 and see what happens...

Brian

 

[Shane Brasher]

Hello All,

Browsing is always based off of WINS and/or broadcasts. Because the browser
service relies on server broadcasts, its communication is connectionless
and by definition unreliable. Because a server's browser role is defined
dynamically with periodic elections, determining the flow of communication
used to provide the browse list to a specific client computer can be
difficult. When domains are split across routers or IP subnets, each
segment will function as an independent browsing entity with its own Master
Browser and Backup Browsers. Therefore, browser elections will occur
within each network segment. Domain Master Browsers are responsible for
spanning the network segments to collect computer name information for
maintaining a domain-wide browse list of available computers in the domain.
Browsing of a domain split across multiple network segments is only
provided in Windows NT Server, so at least one Windows NT Server computer
must be on each network segment to be able to browse the entire domain.

Questions
**********
1. ) Using the browstat utility as per:

188305 Troubleshooting the Microsoft Computer Browser Service
http://support.microsoft.com/?id=188305

What do your computers think is the master browser?

2.) Do you have WINS installed? If so, do you see the 1B entry from within
the WINS database?

You do not need to have the computer browser service running in order to
browse. The computer browser server allows the computer to take place in
the browser election. You can set the domain master (which by default
should be the domain controller) to always win the browser election by a
registry setting.

hklm\system\ccs\services\browser\parameters and set "isdomainmaster" to
"true" and "maintainserverlist" to "yes".

3.) Can you check these values on the domain controller and see if you have
a different value?


Shane Brasher
MCSE (2003,2000,NT),MCSA Security, A+
Microsoft Platforms Support
Windows NT/2000 Networking

 

[Brian]

Sorry for not responding sooner...

1) using browstat, other computers see the proper server
as the master browser - the PDC.
2) yes, the "1B" entry is in WINS
3) the PDC is set to TRUE & YES and the BDC is set to
FALSE & YES. Although the BDC is set this way, a
browstat view shows only {W, S, SQL, BDC, TS, NT}, not
even any PBR or BBR.

Thanks for your response. If you'd prefer you can email
me directly at bdipaolo <A> cscu.ca..., whatever. Thanks
again.
Brian

 

[Shane Brasher]

Hello Brian,

Are any of your domain controllers multihomed?

Shane Brasher
MCSE (2003,2000,NT),MCSA Security, A+
Microsoft Platforms Support
Windows NT/2000 Networking