Configure FC2 as Bridge

[Nigel Wade]

Franco wrote:

> 
> Hi, i have your same output of ifconfig, when i restart
> the network i see that just eth0 is in promiscuous mode seams that
> eth1 don't is in this state. How can i do to change state?
> How can i do to controll the bridge ( firewall ) from other network?
> I need to add another NIC CARD ?
> Best regards.
> 

I have a custom init.d script which starts my bridge. In that I have the 
follwing code:

     brctl addbr bridge
     for card in $CARDS; do
         brctl addif bridge $card
         ifconfig $card promisc 0.0.0.0
     done

where $CARDS contains a list of the cards I'm adding into the bridge. The 
cards are put into promiscous mode here, with the ifconfig command. Is there 
an option you can add into /etc/sysconfig/network-script/ifcfg-eth1 which 
will put it into promiscuous mode, something like PROMISC=yes?

As to network cards, you only need 2 to make a bridge. The bridge interface 
is a pseudo-interface which you use to communicate with the bridge device. 
If you are not intending to communicate with the bridge over the network you 
don't need to ifconfig it and give it an IP. For a bridging firewall this 
makes it even more secure as it can then only be accessed from the console. 
But it makes it much less convenient to administer.

You can see what the status of the bridge is using brctl, for example to see 
what bridges are up and running:

# brctl show
bridge name     bridge id               STP enabled     interfaces
bridge          8000.0001034126cc       yes             eth0
                                                         eth1
To see what MACs it's got in it's address table:

# brctl showmacs bridge  # (in your case this would be br0)
port no mac addr                is local?       ageing timer
   1     00:00:e8:86:15:9e       no               120.45
   1     00:00:e8:86:17:23       no               211.15
   2     00:04:76:d6:d2:0e       yes                0.00
...




-- 
Nigel Wade, System Administrator, Space Plasma Physics Group,
             University of Leicester, Leicester, LE1 7RH, UK
E-mail :    nmw at ion.le.ac.uk
Phone :     +44 (0)116 2523548, Fax : +44 (0)116 2523555