Network: Bridge: bridging two networks

(last edit: 2001-08-25) First let me scetch the situation in which I used this so it's application may become clear and you can perhaps use it in the same way. I have a freebsd router here that is connected to the intenet. Connected to that are two networks with windows machines. Basically windows file sharing uses netbui/netbios as a protocol to do it's filesharing thing. Since this protocol won't let itself be routed it was impossible to reach a windows machine in network 2 from a windows machine in network 1. You could see the computer names, but clicking on them didn't work. To be able to use windows file-n-printer sharing I turned on bridging. What (transparent)briding does: A transparent bridge learns the network's topology from the source address of each incoming frame. It then uses this information to create a table of the paths used by the hosts so that it can use the same paths to forward network traffic. Network hosts do not detect the presence or operation of transparent bridges. How to do it: At the time I'm writing this I have install FreeBSD 4.2-STABLE Activating this should be fairly easy, I personally did it in like 5 minutes (not including kernel recompile) 1 Edit you kernel config file (should be in /usr/src/sys/i386/conf ) and ad the following lines into your config file: #----- # Options required for bridging # options BRIDGE options IPFIREWALL options IPFIREWALL_DEFAULT_TO_ACCEPT #----- The last two options also enable bridging for non-ip packets like the ones windows file sharing use. 2 After this you should recompile your kernel. If you don't know how click here 3 Add the following line(s) to /etc/sysctl.conf net.link.ether.bridge=1 If you want the bridged packets to be filtered by ipfw(8), you should also add: net.link.ether.bridge_ipfw=1 4 Reboot your machine. How to enable bridging is also described in the freebsd handbook. To go there click here I hope it works as easily for you as it did for me. And as we say in holland, Oogjes dicht en snaveltjes toe... ;^) Sjoerd.

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