I have created three instance in openstack . First is source machine , second machine is the machine on which i am running some application and third is destination.

*First machine(source)* details:*

IP ADDRESS:- 172.16.1.11 default gateway:- 172.16.1.1 Floating IP:- 192.168.1.103

Second Machine (on which my application is running) details:

IP ADDRESS:- 172.16.1.12 default gateway:- 172.16.1.1 Floating IP:- 192.168.1.104

Third Machine(Destination) details:

IP ADDRESS:- 172.16.1.13 default gateway:- 172.16.1.1 Floating IP:- 192.168.1.105

I want to send the packet from source to destination through second machine. So I am trying to delete the default gateway of source machine , So that i can add one static route for eg.

On source machine for adding the gateway

route add default gw 172.16.1.12 dev eth0

But when i am trying to delete the default gateway of source machine

i.e route del default gw 172.16.1.1 dev eth0 ,

My instance got hanged and i am not able to do any thing in that instance.

So can you tell me how to set second machine as default gateway , So that packet going from source to destination passes through second machine.