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bridge-utils for Debian From ifupdown 0.6.0 we have a really configurable /etc/network/interfaces so from now on one can configure almost anything he wants of the bridge using the Debian standard way of configuring an interface. To be able to do that I have included a couple of scripts that are marked as configuration files for this package, so that you can keep any changes you make to them from one version of the package to another, suggestions for enhancements are welcome. So, to setup a basic bridge you just need to add something like this to /etc/network/interfaces: auto br0Well, after setting this, an ifup br0, or the next reboot, should let you have a bridge up and running, after waiting for the ports to get to the forwarding status, of course. This bridge will be using all your Ethernet cards, as we have stated on the bridge_port line. Now the Debian bridge setup scripts will wait for it to get ready to work. They do this by trying to guess the maximum time that the bridge will need to get to the forwarding status, and by default, they will wait for the bridge to get there, or for the estimated maximum time to go by. This is done so that the services that are loaded after the bridge setup have a working network interface and don't fail because the bridge is still not working. See bridge_maxwait if you want to change this behaviour. An example of a little more complex bridge setup could be: auto br0In this example we select the ethernet devices that we want to add to the bridge, also we change the bridge default priority to a higher one so that this bridge becomes the root (if there are no bridges with higher priority on the net, that is) and also we lower priority of port eth1 so that it is not used if there are other ports with higher priority to reach the same destination, at the end we lower the default forward delay. A little explanation on the new options that can be used on /etc/network/interfaces to setup the bridge, so you don't have to go and look at the scripts... bridge_ports <interfaces>this option must exist for the scripts to setup the bridge, with it you specify the ports you want to add to your bridge, either using "none" if you want a bridge without any interfaces or you want to add them later using brctl, "all" if you want all the Ethernet interfaces to be added to the bridge, or a list of the interfaces you want to add separated by spaces, for example: bridge_ports eth0 eth4You should not put any lines to configure the interfaces that will be used by the bridge, as this will be setup automatically by the scripts when bringing the bridge up. bridge_ageing <time>set ageing time, default is 300, can have a fractional part. bridge_bridgeprio <priority> set bridge priority, <priority> is between 0 and 65535, default is 32768, affects bridge id, lowest priority bridge will be the root. bridge_fd <time>set bridge forward delay to <time> seconds, default is 15, can have a fractional part. bridge_gcint <time>set garbage collection interval to <time> seconds, default is 4, can have a fractional part. bridge_hello <time>set hello time to <time> seconds, default is 2, can have a fractional part. bridge_maxage <time>set max message age to <time> seconds, default is 20, can have a fractional part. bridge_maxwait <time>forces to <time> seconds the maximum time that the Debian bridge setup scripts will wait for the bridge ports to get to the forwarding status, doesn't allow factional part. If it is equal to 0 then no waiting is done. bridge_pathcost <port> <cost>set path cost for a port, default is 100, <port> is the name of the interface to which this setting applies. bridge_portprio <port> <priority>set port priority, default is 128, affects port id, <port> is the name of the interface to which this setting applies. bridge_stp <state>turn spanning tree protocol on/off, <state> values are on or yes to turn it stp on and any other thing to set it off, default is on, and really this must be on, don't turn it off unless you really know what you are doing. The default values shown here are current values as of this writing, but as they are not related to this package but to the bridge code itself, can change anytime. As you can see this new options are just an interface to call brctl and change that setting of the bridge, you can get more info for them on the man page of brctl. -- Santiago Garcia Mantinan <manty@debian.org>, Sat, 23 Jun 2001 21:45:36 +0200 |