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