iproute2 - eth1 'RTNETLINK answers: Invalid argument'

docawk · 08-13-2009, 12:06 PM

I just added another NIC to a machine that I want to connect to a different LAN area. Usually I never had problems setting up routing via iproute2 utilities.
The newly added NIC has eth1 assigned via udev (in boot process eth0 is assigned, but I need that interface name to be associated to the existing internet bound 100mBit line)

I am running Debian 'lenny' with kernel 2.6.30.3 (quite all network options compiled in).

Setting up the interface via /etc/network/interfaces

Code:

iface eth0 inet static
        address XXX.XXX.250.188
        netmask 255.255.255.248
        network XXX.XXX.250.184
        broadcast XXX.XXX.250.191
        gateway XXX.XXX.250.186

auto eth1
iface eth1 inet static
        address 192.168.11.11
        netmask 255.255.255.0
        network 192.168.11.0
        broadcast 192.168.11.255

works fine and shows in 'ip route' properly

XXX.XXX.250.184/29 dev eth0 proto kernel scope link src XXX.XXX.250.188
192.168.11.0/24 dev eth1 proto kernel scope link src 192.168.11.11
default via XXX.XXX.250.186 dev eth0

The way I want to act is introducing the default gateway on eth0 in the main routing table and set up a separate tabel for routing packets destinated to LAN.

Code:

/sbin/ip route flush table main
/sbin/ip route add XXX.XXX.250.186 dev eth0 src XXX.XXX.250.189
/sbin/ip route add 192.168.11.11 dev eth1 src 192.168.11.9
RTNETLINK answers: Invalid argument
/sbin/ip route add default via XXX.XXX.250.186 dev eth0
/sbin/ip route flush cache

So it seems to me to iproute2 eth1 is not valid.
Anybody a suggestion?

Thanks

docawk · 08-13-2009, 02:37 PM

Problem solved. My fault.

wrong way to use ip route. Should add destination with source address on interface, not mixed up.

Code:

/sbin/ip route add XXX.XXX.250.184/29 dev eth0 src XXX.XXX.250.189
/sbin/ip route add 192.168.11.0/24 dev eth1 src 192.168.11.11
/sbin/ip route add default via XXX.XXX.250.186 dev eth0
/sbin/ip route flush cache

works fine;-)

Thanks anyways.

mgautam · 09-24-2009, 08:34 AM

Hi,

I am facing a similar problem. I am using ip utility on Linux 2.6.26 to create a default route. A simple configuration like below is giving me error -RTNETLINK answers: No such process

machine-1
eth0:192.168.1.2

machine-2
eth0:192.168.1.1
eth1: 172.1.1.1

I want to ping 172.1.1.1 from 192.168.1.2 via ip rules only. Main routing table does not contain any entry. Here are the commands that I give on machine-1:

Code:

ip rule add from 192.168.1.2 iif lo table eth0tbl
ip rule add to 192.168.1.2 iif eth0 table eth0tbl

Added route to eth0tbl -

Code:

ip route add 192.168.1.0/24 dev eth0 table eth0tbl

This succeeds.

Now I am trying to add default gw to eth0tbl.

Code:

ip route add default via 192.168.1.1 dev eth0 table eth0tbl
RTNETLINK answers: No such process

I have tried adding default route to the main table but gives same error.

Code:

ip route add default via 192.168.1.1 dev eth0
RTNETLINK answers: No such process

I am not sure what am I doing wrong. Could you help me locate the problem.

Many thanks

mgautam · 09-25-2009, 08:25 AM

Problem solved -

I was flushing the Main table before creating the default gateway.

Perform all the operations first, to enable the gateway reachable via the host network route entry. Then add the default gateway entry in the table you want. And lastly flush the Main and the cache tables.

Thanks