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centos different subnets problem

Hello i have 2 centos machines but i have a problem with this both machine

my machines has different subnets with their gateway i mean machines ip addresses
188.72.xxx.188
188.72.xxx.189

and my gateway is :

217.20.xxx.1

so i have added this lines to route-eth0 :

ADDRESS0=217.20.117.1
NETMASK0=255.255.255.255

so i do not need to write
route add -net 217.20.117.1 netmask 255.255.255.255 dev eth0
but i still need to write :
route add default gw 217.20.117.1
manually how could i do this automagically
only there is a triick if i write it to network scripts it is loading before route-eth0 so it returns me unknown host or unreachable machine

Thank you

Martin_J_Parker

Just add to your route-eth0:
GATEDWAY0=217.20.117.1

CahitEy

ASKER

nope i have tryed not workd my netstat -rn must look like this (as seen on code file )

and i have not seen only the last line automagicaly

Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
217.20.117.1    0.0.0.0         255.255.255.255 UH        0 0          0 eth0
188.72.xxx.0     0.0.0.0         255.255.255.0   U         0 0          0 eth0
0.0.0.0         217.20.117.1    0.0.0.0         UG        0 0          0 eth0

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Martin_J_Parker

Have you restarted the eth0 ethernet since you changed the file?

CahitEy

ASKER

yes exactly :) if i add the line as :
GATEWAY0=217.20.117.1

then my netstat table seems like
217.20.117.1 217.20.117.1 255.255.255.255 UH 0 0

and my service network restart is returning unknown gateway :) unfortunately i have to route gateway at the end of all operations

Martin_J_Parker

What version of CentOS is it?

CahitEy

ASKER

5.4 latest version also i have tryed for 4.8 and ubuntu that is only working correctly and automagically on fedora 12 all the other linux versions needs to make it manually

Martin_J_Parker

On RedHat Enterprise Linux 5.3 (which is meant to be the same base code as CentOS 5.3) my default route is set in /etc/sysconfig/network, which contains the following 4 lines:

NETWORKING=yes
NETWORKING_IPV6=yes
HOSTNAME=myhostname.mydomain.com
GATEWAY=10.1.1.1

so it might be worth seeing if setting the gateway in that file does the trick for you.

CahitEy

ASKER

i have tryed this also
it is ignoring this on all linux dists exept fedora 12 so fedora is working like a charm just when i set it on network adapter settings

Martin_J_Parker

Hmmm - one of those should work - you could put a script in /etc/rc3.d so it sets the route at startup (a bit of a kludge but effective) but that doesn't explain why the other files aren't affecting things.
Do you know about how the /etc/rc?.d directories work?

CahitEy

ASKER

nope :(

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Martin_J_Parker

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Martin_J_Parker

By the way, S10myscript would run before S10network because it comes first alphabetically - that's why I chose S11myscript.

You may need to add the path to the route command into the script as I'm not 100% sure what the PATH will be set to at that point!

arnold

You need to add a default gateway for each segment.
using the metric you can adjust the weight through.

Why/how does your eth0 interface have two separate segments that are completely different from the default gateway segment?
217.20.117.1 is no where near the 188..x.x.x/24 network.

The description in your question is missing some detail.
you can use the route add directive as martin_J_par posted. The problem is that the traffic might not find itself back or the 188.x.x.x Ip will not be the source of the packets sent from your system.