Download your favorite Linux distribution at LQ ISO.
Go Back > Forums > Linux Forums > Linux - Networking
User Name
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.


  Search this Thread
Old 02-16-2006, 06:07 PM   #1
Registered: Aug 2004
Location: Argentina
Distribution: slackware 12
Posts: 211

Rep: Reputation: 30
Question 1NIC->ok, no config needed; 2NICs->no connection al all (??)

hi... gonna try to keep it short and clear:
I've got 2 boxes, trying to make this scheme works:


both boxes runnin' slack10.2
both nics on box1: 3com
nic3 on box2: realtek
boxes linked thru twisted cable.

when I put nic2 in box1, under windows nic2 is auto-configured and the internet connection is ok, but under linux such connection get lost, dmesg don't say absolutely nothing related eth*; ifconfig only shows local; nic1_led=bright,nic2_led=dark. -if I take off nic2, internet is back.

question 1: what should I do to get internet connection on box1 under linux? (plz. be generous with examples..I've got not a clue about net configs)

question 2: how to configure both boxes to connect each other this way: linux<->linux and windows<->linux ?
(with a telnet/ssh connection is enough by now)

waitin' 4 any help,
thanks in advance
Old 02-16-2006, 06:32 PM   #2
LQ Guru
Registered: Jan 2003
Location: Seymour, Indiana
Distribution: Distribution: RHEL 5 with Pieces of this and that. Kernel, KDE 3.5.8 and KDE 4.0 beta, Plu
Posts: 5,700

Rep: Reputation: 62
What IP are you assigning to the second nic? A non routable one like 192.68.***.***.

If so have you defined a gateway on the 2nd nic. If so do not. What you need on the second nic is an IP and subnet defined. No gateway. Then on the second computer you use the IP of the second nic for the gateway on it.

computer 1
nic 1 IP ***.***.***.***
nic 2 IP, subnet
computer 2
nic 3 IP, subnet, gateway

To have the 2nd computer to see the other you need to add masquerade command on the 1st computer. Can be a complex thing to setup without more details.

What you are after is a simple firewall with masquerading. Check out this site and there are many tutorials and scripts there. . Also down near the bottom is one called easy firewall generator. It ask questions about your network and creates a iptables script that you can use.

Hope this helps.
Old 02-16-2006, 06:53 PM   #3
Registered: Aug 2004
Location: Argentina
Distribution: slackware 12
Posts: 211

Original Poster
Rep: Reputation: 30
thanks 4 answer Brian,
I'm not assigning any ip adress to no nic: I don't know howto.
which command handle such task? --I remember you that acording to my dmesg, my box doesn't "see" any nic (no single mention of any eth device)
is that normal?
how should I reffer to the nics if my box don't see it?
selecting the dinamic-config (dhcp or something like that) is the only way I know to "configure" the cards. -in fact, all of the job is made by such dinamic configuration-I really do nothing.
do I need the ip address my isp is assigning to me?
I guess this 2 steps are needed:
1) assign to nic1 my ip,
2) change the nic2 ip..
(plz.correct me if I'm wrong)
..but with which command should I do that?



Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
snort config help needed phsythax Linux - Security 3 11-21-2005 08:03 AM
Help needed for xorg config jjlinux Linux - Hardware 2 05-29-2005 01:43 AM
2NICs 2 IP's 1 network strangeslack Linux - Networking 1 02-14-2005 07:44 AM
Unable to ping internet through RH7.3 box w/ 2nics dc78 Linux - Networking 3 02-07-2004 08:56 PM
VSFTP config help needed dquick Linux - Networking 0 06-19-2003 11:43 AM > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 05:08 PM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration