Adding network routes in Windows and Linux

^{Created: 2018-10-03 00:46:56 | Last modified: 2018-12-17 23:34:33} ^{| By: Nova}
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This is how to create a route in Windows and linux and make it persistent

Here are some how-to docs for adding routes into Windows and Linux. Windows is done using the command prompt and Linux using a terminal.

Windows Routes

Open up a command prompt (cmd)

Print a list of routes, persistent routes are under the persistent route section

route print

Add a route. In this example I have a server in a vlan (10.30.0.0/24) which needs to route to another vlan (192.168.0.0), and it will do this via gateway 10.30.0.1

-P at the end is to keep it persistent after a reboot
Check that the route is persistatent once done by running the "route print" command

#Basic Example
route add destination MASK subnetmask gateway -p

#Example
route add 192.168.0.0 MASK 255.255.255.0 10.30.0.1 -p

#Working with a metric and interface
route add destination MASK subnetmask gateway METRIC metric IF interface -p

#Example - Adding with metric and interface
route add 192.168.0.0 MASK 255.255.255.0 10.30.0.2 METRIC 2 IF 2 -p

Testing the route. To test the route, run a tracert to the destination, confirm that the next hop is out of the desired gateway. In this example I will tracert to a destination in the other vlan

tracert destination

#Example
tracert 192.168.0.4

To delete a route (In this example I will delete the 192.168.0.0 destination I added above)

Confirm removed by running the "route print" command

route -p delete destination

#Example
route -p delete 192.168.0.0

Linux Routes

These have been tested in Centos7

To list routes inside Linux

ip route

To add a route in Linux (not persistent)

ip route add 103.99.81.68/32 via 10.30.0.1 dev eth0

To remove a route inside Linux

ip route del 103.99.81.68/32 via 10.30.0.1 dev eth0

To add a default route inside Linux

route add default gw 10.30.0.1

In Centos/Redhat Linux to make the routes persistent you need to create a file 'route-eth0" with the route information in. This is under /etc/sysconfig/network-scripts/ . You would change the -ethX part depending on the interface you are wanting the route in.

vim /etc/sysconfig/network-scripts/route-eth0
103.99.81.68/32 via 10.30.0.1 dev eth0

In Debian, edit the following file and add this under the interface.

vim /etc/network/interfaces
iface eth0 inet static
        address 103.99.81.61
        netmask 255.255.255.0
        network 103.99.81.0
        broadcast 10.9.38.255
        post-up route add -net 10.0.0.0 netmask 255.255.255.0 gw 10.30.0.1

#Example of a delete
post-up route del -net 10.0.0.0 netmask 255.255.255.0 gw 10.30.0.1

You can restart the network to confirm that the route is in place

systemctl restart network
ip route

default via 10.30.0.1 dev eth0 proto static metric 100
103.99.81.68 via 10.30.0.1 dev eth0 proto static metric 102