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-   -   forward broadcast packets to another subnet (

VultureCulture 10-08-2002 05:10 PM

forward broadcast packets to another subnet
hello again,
the situation is as follows:
i am connected to a LAN via one linux gateway (suse 8), through which other pcs in my own private network are able to gain access to the "outer LAN" and, from there, to the internet as well. sad but true, at least one of these private pcs is required to have windows 2k running. this works quite fine except for the windows "network neighbourhood", where i can only see hosts on my private net but not on the one on the other side of the gateway. i have already been told here that this should be because the network neighbourhood sends broadcast messages to the net in order to locate hosts, but these packets are generally not forwarded by routers.
i tried to gather some information elsewhere, but surprisingly i couldn't find people with similar problems. i know that for example some cisco boxed routers support broadcast forwarding, so this should generally be possible with software routing as well.
now the question is: how? how do i forward broadcast packets from one interface/subnet of my router to the other?

thanks in advance for your time,


Mara 10-08-2002 05:36 PM

Maybe a kind of VPN (Virtual Provate Network)?

VultureCulture 10-09-2002 09:52 AM

i don't know much about that, but it seems only to be a workaround to the original problem. also, setting up a vpn might be quite oversized for a small private LAN like mine... there has to be a simple solution.

Mara 10-09-2002 11:55 AM

The problem is that broadcast packages are supposed to be not routed outside a subnet. Every solution that allows it is a workaround. You may try to make all your machines (if you can; security reasons etc) in one network. You can use VPN or just make a network submask diffeent. For example if you've got machines with 192.168.0.x and 192.168.1.x adresses you can change the netmask from 24 to 23.

rohang 10-09-2002 08:56 PM

What sort of router do you have? If it's a Cisco, you can use the ip-helper command to do this.

If it's another vendor, I'm not sure how you'd do it (if at all).

VultureCulture 10-10-2002 06:56 AM

thanks for your replies.

it's not a boxed router, just a linux machine running routing software which came along with suse 8.0., so i think it should well be possible to route broadcast packets somehow.

yes, you are right with the workaround, but sadly i have no influence to the LAN i am connected to, so i can't change anything there. this LAN got public IP addresses, so i can't just give similar IPs to my other machines.

Mara 10-10-2002 01:18 PM

So I guess VPN is the best solution for you (if possible to install).

oediv 10-22-2003 05:43 PM

Was wondering if anyone found a software solution to this, because im strangling with the same problem over here...

siddiqu 10-23-2003 04:40 AM


It is not necessary to route the broadcast packets. I have faced this same issue.

Then we have setuped WINS Server on the subnets using Win2k. It can replicate the names between the subnets.


oediv 10-25-2003 05:14 PM

that wasnt the only reason why i wanted to forward things like broadcast, because connecting and hosting gameservers doesnt seem to work for 100% either.

I tried to setup my linux-server as wins-server by using wins support=yes in my smb.conf and entered my server ip as wins-server but that still doesnt seem to solve the problem...

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