HowTo: Add a Persistent Static Route in Redhat Enterprise Linux | ItsyourIP.com
How do I create persistent static routes in Red Hat Enterprise Linux 4?
How do I set my static routes in Red Hat Enterprise Linux 2.1?

To add a persistent static route in Redhat Enterprise Linux create a file called route-X in the /etc/sysconfig/network-scripts/ directory

Example:

GATEWAY0=192.168.1.1
NETMASK0=255.255.255.0
ADDRESS0=10.10.10.0

GATEWAY1=192.168.1.1
NETMASK1=255.255.255.0
ADDRESS1=20.20.20.2


To check:
# route (-e or -ee)