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Community Member


i'm having problems with network neighborhood browsing over my wan. it was suggested that i forward udp 137 and 138 via 'ip forward-protocol udp 137' and '138'.

Unfortunately, when i do a 'show run' on the 7206 and the 2620, i don't see this statement anywhere. i don't know if it's because it didn't take or this command isn't really supported on those routers.

can anybody help?


Re: forward-protocol

Those two ports are enabled by default.

Re: forward-protocol

Are you using ip-helper to another subnets broadcast address? If so, make directed broadcasts aren't disabled on the destination network interface for that subnet. Same thing in other direction.

You may also need to forward port 139

Community Member

Re: forward-protocol

More Detail:

On 2620 subinterface, I have and ip-helper address configured to send dhcp to remote dhcp server.

I don't have directed-broadcast enabled - still not sure why i would need it.

pc's on local network, but separate vlan than dhcp and wins browse fine, once those pc's are moved to remote network pc-2950-2620-t1-7206-6509-serverVlan they get an immediate error msg. when attempting to browse the network via net. nieghborhood

i just added port 139 and it did show up in the 'show run'

Re: forward-protocol

Do you have a WINS server on each subnet and configured on PCs?

If not, then windows networking is broadcast traffic and ip-helper forwards the protocols allowed by the forward-protocol command. If you have ip-helped configured for the DHCP server then these broadcasts are going to sent to the DHCP server as unicast packets.

You might need to setup a ip-helper pointing to remote network IP subnet broadcast address. This is a directed broadcast which needs to be enabled on the router interfaces.

Whats the error they are getting?

Re: forward-protocol

Commands which are by default enabled, will never appear on the config, even if you give it again and again.

Do this

if you give

no ip forward-protocol udp 137

no ip forward-protocol udp 138

These two commands appear as

no ip forward-protocol udp netbios-ns

no ip forward-protocol udp netbios-dgm

now if you give the command without a "no"

ip forward-protocol udp 137

ip forward-protocol udp 138

both commands will disappear.

THis proves my point.

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