Installed New Ethernet Card. Now Software Bridge Doesn't Work.

From: Gazza (gazza_at_192.168.1.1)
Date: 11/30/03

  • Next message: ynotssor: "Re: Sending email to dial up Linux box" 
    Date: Sun, 30 Nov 2003 00:24:48 +0000

    Hi,

    I have a 3-PC 10/100 Mb/s Ethernet home network, with all machines runing
    Mandrake Linux 9.1. I have two NIC's in my main computer, PC 1. One is
    installed in PCI slot 2, the other is in PCI slot 4. In linuxconf, I set
    up their IP addresses and FQDN's (respectively) as:

    192.168.1.1, bedroom.masterton.net (alias 'bedroom') and
    192.168.2.1, bedroom.masterton2.net (alias 'bedroom2').

    PC's 2 and 3 were set up with IP addresses and FQDN's (respectively) of:

    192.168.1.2, lounge.masterton.net (alias 'lounge') and
    192.168.2.2, kitchen.masterton2.net (alias 'kitchen2').

    Because PC's 2 and 3 were on different sub-nets, it was difficult to access
    one from the other (and vice versa). So, I set up bridging on PC 1 by
    issuing the following commands:

    brctl addbr br0
    brctl addif br0 eth0
    brctl addif br0 eth1
    ifconfig eth0 0.0.0.0
    ifconfig eth1 0.0.0.0
    ifconfig br0 192.168.1.1

    and changed PC 3 to 192.168.1.4/kitchen.masterton.net/kitchen. Everything
    worked beautifully, so, I added the above brctl lines to the bottom of my
    /etc/rc.d/rc.local file so that the bridge comes into play at the end of OS
    loading. Works fine.

    The problem started when I installed a third NIC in PC 1, in PCI slot 3.
    This Ethernet card is connected to a cable modem and, in linuxconf, I set
    it (eth2) to get it's IP address by selecting 'DHCP'. I re-booted and did
    an ifconfig. It showed everyting as expected, except that eth2 did not
    show an IP address, but, underneath, there was something referred to as
    'eth2:9', which had an IP address I recognised as belonging to a pool of
    IP's that my ISP uses. I could ping this dynamic address. So, everyting
    was okay. However, I could no longer ping PC 3 (192.168.1.4). 192.168.1.1
    was pingable and so was PC 2 (192.168.1.2). What's up?

    Sorry about being so verbose, but I thought I'd better give as much info. as
    possible.

    Yours,
    Gary Hayward.

  • Next message: ynotssor: "Re: Sending email to dial up Linux box"

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