[CentOS] Static routing on CentOS

Wed Feb 26 06:28:01 UTC 2014
Jatin Davey <jashokda at cisco.com>

Hi All

I have two hosts. Host A and Host B

Host A routing table
------------------------
[root at localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
172.29.110.0    172.29.109.1    255.255.255.0   UG    0 0        0 eth0
172.29.109.0    0.0.0.0         255.255.255.0   U     0 0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     0 0        0 eth0
0.0.0.0         172.29.109.1    0.0.0.0         UG    0 0        0 eth0

HOST A IP address : 172.29.109.254



Host B routing table
-------------------------
[jatin at localhost ~]$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
172.29.110.0    0.0.0.0         255.255.255.0   U     1 0        0 eth0
20.20.20.0      0.0.0.0         255.255.255.0   U     0 0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002 0        0 eth0
0.0.0.0         172.29.110.1    0.0.0.0         UG    0 0        0 eth0

HOST B Ip address : 172.29.110.93


Host B basically houses some simulated devices which are configured in 
the ip address range of 20.20.20.1 to 20.20.20.254. The netmask being 
used here is 255.255.255.0

I want to configure a static route on HOST A so that they can reach the 
simulated devices running on HOST B which are in the ip address range 
20.20.20.1-20.20.20.254 , I am trying the following command but it does 
not configure the static route for me.

[root at localhost ~]# route add -net 20.20.20.0 netmask 255.255.255.0 gw 
172.29.110.93
SIOCADDRT: Network is unreachable


Any help is greatly appreciated.

Thanks
Jatin