macpiano
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One building's computers netbios cannot be seen in all the rest of the buildings.
One building's netbios names do not show up in the other buildings. We are W2K3 domain with 5 buildings connected by fiber. There are DCs at each buidling. One building can see all the rest of the computers in all buildings but the other 4 buildings cannot see that one building. What else is interesting is that some of the computers are notebooks and when using the wire can see everything but on wireless cannot see its own building.
I have a Cisco 4500 core switch.
I have a Cisco 4500 core switch.
Everything is on the same subnet? Do you have any ACL's defined?
ASKER
The main problem happens between subnets as there are 5 buildings. 1 building can see just about everything, the other 4 can't see that building.
Netbios is a broadcast protocol. It is not forwarded between subnets. WINS was developed to deal with this, basically by putting a WINS server in each subnet and having all of the WINS servers share their netbios data. If you have 5 different subnets and want reliable netbios info that traverses these subnets, you need a WINS server in each subnet.
ASKER
Sorry I'm not well versed in this but is that done on the DC in the building? I can't imaging that it is in DHCP because the servers have static ip addresses and their netbios names get replicated in normal circumstances
Gary
Gary
It doesn't matter if you are static or DHCP. Netbios announcements are made to the broadcast address 255.255.255.255. Routers do not forward broadcasts between subnets. Thus netbios announcements will not travel between subnets. Basically, netbios sucks compared to DNS, but MS built years of technology on top of Netbios. Even though Active directory is totally DNS based, there are still many parts of the MS portfolio that will try and use Netbios info.
While I can't speak to why it appears that you get netbios info sometimes(maybe an app is falling back to dns), I can state unequivocally that netbios is not designed to work across subnets and WINS is the MS solution to allow it to do so.
While I can't speak to why it appears that you get netbios info sometimes(maybe an app is falling back to dns), I can state unequivocally that netbios is not designed to work across subnets and WINS is the MS solution to allow it to do so.
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