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CROSSOVER connection help

Posted: 2011/02/07 18:52:05
by myvideo
Hi guys,
i am not able to set up a crossover connection between 2 CENTOS 5.5 boxes.
Made myself a cable according this guide [code]http://en.wikipedia.org/wiki/Ethernet_crossover_cable[/code] .

BOX 1 - eth0:

IP:
192.168.2.1
MASK:
255.255.255.0
GATEWAY:
192.168.2.2
PRIMARY DNS:
192.168.2.2

BOX 2 - eth0:

IP:
192.168.2.2
MASK:
255.255.255.0
GATEWAY:
192.168.2.1
PRIMARY DNS:
192.168.2.1

Turned off the firewalls, rebooted, tried to PING the boxes and got no response... Can anybody help me?

Thanks

Re: CROSSOVER connection help

Posted: 2011/02/07 19:48:37
by hansolo
Hi,

I think you must not make Gateway IP to other Box but 'real' gateway like router's or your ISP's
also DNS is not other box IP !

CROSSOVER connection help

Posted: 2011/02/07 20:55:51
by jlehtone
First, 1Gbps network cards tend to have MDI-X feature. With it one
does not need cross-over cable; any patch will do. If either machine
would have such NIC, then you could rule out errors in selfmade cable.

Second, have you looked the interfaces with 'ethtool'? It can show
whether you have link. Alternatively, some motherboards (BIOS)
do have "link test" too.

Third, for a connection between two machines, neither gateway nor
DNS is needed. The purpose of gateway parameter is to tell a device
in local subnet, through which traffic to other subnets should be routed.

DNS is just name resolution. If you want to name the other machine, you
can simply add a line to /etc/hosts.

Re: CROSSOVER connection help

Posted: 2011/02/08 12:07:04
by myvideo
Thanks guys!
"ethtool eth0" solved my problem. I have 2 identical Intel 1530SH servers, but the NICs are swapped!!!!

I've never seen anything like this before...

Re: CROSSOVER connection help

Posted: 2011/02/08 14:32:21
by jlehtone
:-D

It is udev these days that enumerates devices, and it can enumerate them non-
systematically. The worst that I have seen was swapping of names "eth0" and
"eth1" on almost every reboot. That was Fedora Core. These days Fedora's
udev writes a static rule the first time it finds net devices. That helps on later
reboots.