All right I have two machines.

1) XP with two network cards 1 out to internet(router) and 1 to fc6 machine
2) fc6 with two network cards 1 out to internet(router) and to to XP machine

This should be simple but unfortunately I can't seem to figure it out. I can connect one machine to the other using the internet network cards but I can't using the network cards connecting the two machines directly.

Can someone give me a hand and let me know what I'm doing wrong? Thanks.

Here is what I get when I use ifconfig:

eth0 Link encap:Ethernet HWaddr 00:118:6C:03:41
inet addr:192.168.1.151 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::211:d8ff:fe6c:341/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:137 errors:0 dropped:0 overruns:0 frame:0
TX packets:33 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:19135 (18.6 KiB) TX bytes:6408 (6.2 KiB)
Interrupt:209

eth1 Link encap:Ethernet HWaddr 00:118:6B:EF:7B
inet addr:192.168.1.101 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::211:d8ff:fe6b:ef7b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:13825436 errors:0 dropped:0 overruns:0 frame:0
TX packets:15992993 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1903341621 (1.7 GiB) TX bytes:4286163063 (3.9 GiB)
Interrupt:177 Base address:0x4000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1990 errors:0 dropped:0 overruns:0 frame:0
TX packets:1990 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2213381 (2.1 MiB) TX bytes:2213381 (2.1 MiB)

Here is what I get when I run route:

Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 192.168.1.1 0.0.0.0 UG 0 0 0 eth1

nb. I used:
route del default
route add default gw 192.168.1.1 dev eth1

it's what I had to do to get this working in fc5.

Thanks in advance,

M

Did you connect the two machines with a reverser (crossover) cable? In any case, why would you try to do such a thing? The two machines are connected through the router, anyway. This other connection you're making is redundant.

To be a bit more specific as to why a regular ethernet cable won't work: Ethernet cables are made up of "pairs" of cables. There is a transmit data pair and a receive data pair. If you just hook two machines together with a regular cable, then you would have a transmit pair connected to another transmit pair. There's no way for the transmit data to get to the receive data. Routers connect the transmit to receive (and vise-versa) internally.

Why would I do that? That's easy. My router is a 10/100 and those two network cards are gigabit cards. The files that I transfer from one machine (FC6) to the other (XP) go from 175MB to 4-5GB.

Now I could have made a crossover cable but 1) I'm too lazy and 2) Both network cards are auto-sensing so I don't have to. This did work in FC5 so I'm wondering what I've done wrong.

Well I think I've figured it out so I'm recording it here for posterity. Here's my network setup.

XP
192.168.1.100 (internet card)
192.168.1.150 (card to connect to FC6)

FC6
192.168.1.101 (internet card) device: eth1
192.168.1.151 (card to connect to XP) device: eth0

Remove then add default gateway so card can access the internet. Now I don't appear to need to do this in FC6 but I'm doing it anyway.

route del default
route add default gw 192.168.1.1 dev eth1

192.168.1.1 is the ip of my router.

Add route to get to XP machine.

route add -host 192.168.1.150 dev eth0

Works like a charm! Now all I need to do is figure out how to put it so it works at boot up!

M

Thanks for clearing up both the why and the how. I have wireless in the house, but I may do the same to connect two machines for the same reason. As to what next: put it in an rc.d file?

using two nic cards is also a security isue. If you only use one nick on your server it is possible for someone using the route comand to bypass your server-firewall-gateway-whatever it is, and target another computer on your LAN. JFYI