Multiple eth interfaces, gateways, SuSE 10

b1f30 · 07-10-2008, 08:30 AM

SOLUTION: There is a Java front end for the iSCSI cards in question. They are Q-Logic's, and they have their own networking tools available from their CD. Worked like a charm with the problem below.

SuSE 10 Advanced networking question:

I have 3 interfaces: 1 NIC, 2 iSCSI QLogic.

I want them each to have their own gateway, but I do *not* want a default gateway.

NIC: 10.15.50.10 --> Gateway: 10.15.50.1
iSCSI: 10.15.40.10 --> Gateway: 10.15.40.1
iSCSI: 10.15.30.10 --> Gateway: 10.15.30.1

How to statically assign each their respective gateway?

Thanks!

jschiwal · 07-10-2008, 09:46 AM

Simply use a netmask of 255.255.0.0 and set up routes for each subnet.

Read your documentation for your distro. I don't use debian, but there is probably a standard
configuration file where the routes are listed and then configured using either the "route" or
"ip" command. There is also the /etc/networks file where you
can give your networks aliases.

The route or ip command can be used to configure the routes directly, but it is usually best
to determine the standard method that your distro uses.

Also look at the www.tldp.org website. There is an O'Reily book there "Network Administrator's Guide" which has a lot of general networking information.

farslayer · 07-10-2008, 11:32 AM

Debian Linux static routes

# cat /etc/network/interface

auto eth0
iface eth0 inet static
address 192.168.1.2
netmask 255.255.255.0
gateway 192.168.1.254
up route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.2.1
down route del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.2.1

Ack !! read Debian in the last response and provided that info instead of Suse.. lets try again..
http://www.susegeek.com/networking/h...-opensuse-110/
http://linuxmafia.com/pub/linux/suse...chapter10.html
http://www.novell.com/documentation/...l/ch14s05.html

b1f30 · 07-10-2008, 11:40 AM

Guys, I'm talking about SuSE - not Debian. :-)

farslayer · 07-10-2008, 11:31 PM

Yes and I put the links for Suse at the bottom of my post when I noticed the error...

Vit77 · 07-11-2008, 01:15 AM

I don't know Suse specific, but I can say about general Unix routing, which works on each *nix.
Generally, system decide which interface should be used according to a single routing table. (Let's avoid discussing the multiple routes etc.)
So, for each destination you should use a certain router. Thus:

Initially, your routing table contains something like this:

Code:

$ netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
10.15.50.0      0.0.0.0         255.255.255.0   U         0 0          0 eth0
10.15.40.0      0.0.0.0         255.255.255.0   U         0 0          0 eth1
10.15.30.0      0.0.0.0         255.255.255.0   U         0 0          0 eth2

Some Unix systems will show something like this:

Code:

$ netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
10.15.50.0      10.15.50.10     255.255.255.0   U         0 0          0 eth0
10.15.40.0      10.15.40.10     255.255.255.0   U         0 0          0 eth1
10.15.30.0      10.15.30.10     255.255.255.0   U         0 0          0 eth2

Anyway, the interface which should be used to reach a certain router is already defined.

Then, just add routes for each destinations via necessary router:

Code:

ip route add 10.50.0.0/16 via 10.15.50.1
ip route add 10.40.1.0/24 via 10.15.40.1
ip route add 10.30.2.1/32 via 10.15.30.1

I think it must solve you problem.

jschiwal · 07-11-2008, 05:20 PM

You can configure routes in YaST2 -> network devices. Also look in /etc/sysconfig/. That is where YaST saves the results, and there should be a commented script where you would enter your routes. The bootup scripts with use these values to set the routes.

There is also a sysconfig editor in YaST2. Enter the search term "route" and you should be able to modify the correct file there.