Network Routing

Configuring Simple Static Route

Static Routes in Cisco Router

Now we will look at the simplest example to configure static routing given the network topology below. Take note that all IP addressing has been configured. So the only things left to do is to configure static routes.

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There are a few check lists before we start the configurations:

This is the syntax for static route in Cisco IOS. There are only 3 parameters needed.

Now we list out all the parameters correspond to each route.

Static Route#1

Understanding Static Routes Commands (from LAN1 to LAN2)

Static Route#2

Understanding Static Routes Command (from LAN2 to LAN1)

What is ‘next hop’ explained

One of the useful trick to configure static IP is to spot the next hop of each route quickly. Remember that we need to specify the Next Hop IP as the third parameter in a static route.

Next Hop refers to the next adjacent router that the local router will forwards the packet to in order to reach the destination network. Next Hop IP is the IP address of the interface of this next hop router that is currently facing towards the local router.

We need to see this from the point of view of a router that we are currently configuring. We refers to this router as the local router. In our example, the local router is Router0; and the remote router is Router1.

Finding the next hop interface in a static route

Suppose that PC1 sends a packet to PC2. This packet will first go to Router0. Then, Router0 will forward it to the next hop router; which is Router1. This packet will arrive at the interface fa1/0 on Router1. Here, the next hop IP is the IP address assigned to the int fa1/0 on Router1 — that is

Note: fa0/0 on Router_1 is not the next hop interface because it is facing towards the internal LAN.