How to make my default gateway permanent in CentOS? So that after a reboot it does not get lost

Question

I have a CentOS running. It is important to have my CentOS available when I am remotely connected to a VPN router. I tried to add a default gateway to the VPN router, but after reboot it goes away. How can i put this as permanent?

ip route add 192.168.2.3 via 10.0.0.1 dev eth0

Answer 1

If i've read your question right, i think you want to add

GATEWAY=192.168.2.3

into /etc/sysconfig/network then reboot or do service network restart to test it.

Although i'm not entirely sure from your question that you do actually want a default gateway at all. I think you may just want to make a static route permanent ?

Answer 2

If anyone is running CentOS with multiple NICs, only 1 is connected to the Internet and you want to make that particular interface to take all the Internet traffic, then add following line in to your /etc/sysconfig/network file:

GATEWAYDEV=network_interface
GATEWAY=default_gateway_ip

Save and restart your network services. This worked for me and nothing else was working.

Answer 3

Just realized, to add below to the /etc/sysconfig/network-scripts/route-your_interface_name doesn't work, must be on the ifcfg file:

default via x.x.x.x dev y

Answer 4

You may be able to add that line to the appropriate /etc/ifconfig.INT (where "INT" represents the appropriate interface), just like we do with dhclient sometimes (notice the leading explanation point inserted as the first character):

!ip route add 192.168.2.3 via 10.0.0.1 dev eth0

(I haven't tried CentOS, but I'm assuming this mechanism should essentially be the same as it is on NetBSD.)