Static and Floating Static routes configuration Explained | The ip route command | CCNA Video -8

#ccna, #ccna_certification, #ccna200_301, #routing, #static_routing #networkingtutorial #ip_route_command #router

This video explains static and floating static route configuration in the routing table. This video is based on the following tutorials.
https://www.computernetworkingnotes.com/ccna-study-guide/ip-route-command-explained-with-examples.html
https://www.computernetworkingnotes.com/ccna-study-guide/static-routing-configuration-guide-with-examples.html
https://www.computernetworkingnotes.com/ccna-study-guide/static-and-floating-static-routes-explained.html

[Video description]
Routers use the routing table to make forwarding decisions. When a router receives a data packet, it compares its destination address with the routes available in the routing table. If it finds a match, it uses that to forward the data packet. If not, it discards the packet.

There are three ways to add and manage routing information in the routing table: automatic, static, and dynamic.
In the automatic method, the router automatically adds and manages the routing information based on the IP configuration we assign to its interfaces.
In the static method, we manually add and manage routing information on all routers.
In the dynamic method, a routing protocol does the same thing.
Static and dynamic routing work with automatic routing. If routes are available on local interfaces, the router automatically adds using automatic routing.

If we manually add routes, it is called the static routing method. If we use a routing protocol, it is called the dynamic routing method. In this network, we will use the static routing method. This method can add three types of routes: static, floating static, and default.

A static route is the single best route for the destination. If we configure it, the router adds it to the routing table and uses it to reach the destination.
A floating static route is a backup route for the second-best route for the destination. If the primary route fails, the router dynamically adds it to the routing table. If the primary route becomes available again, the router removes the backup route and adds the primary route again.
A default route represents all networks. The router uses it only when no other route to the destination is available.
To enable communication between LAN networks available on different routers, we must add their routes to the routing table of all routers. The ip route command in global configuration mode adds a static route.
It accepts five arguments: destination network, subnet mask, next hop IP address or exit interface, administrative distance, and permanent keyword.
The value of these arguments classifies the added route as static, floating static, or default route.

If we specify the network or host address of a particular IP subnet, it is called a static route.
If we use an address that belongs to all IP addresses, it is called a default route.
If we configure administrative distance, it is called a floating static route.

Floating static
A floating static route is a backup route. We use it when the primary route is down. If we use dynamic routing, the routing protocol automatically manages routes in the routing table. For example, if a destination has two routes, the routing protocol compares both routes and adds only the best route to the routing table. It keeps the second route in its own table as the backup route. If the primary route fails, it immediately adds the backup route to the routing table. If the primary route comes online again, the backup route will be removed and added to the primary route again.
In static routing, we have to do all these things manually. We have to define which route is the best and which is the backup route. If we add the second route without specifying its priority, the router uses it for load balancing.
Adding multiple static routes with the same priority for the same destination is useful when you use them for load balancing. However, if you want to use them for backup, define their priority.
Routers use AD values to define priority for routes. An AD value is the trustworthiness of the source. It is a unique number on a scale of 0 to 255. A router can learn routes from many sources. It assigns a unique AD value to each source.

The default AD value of a static route is 1. Use the value 5 for the backup route. With this configuration, Router2 will use the backup route only when the primary route fails. It keeps the primary route in the routing table and the backup route in memory.
A static route with a custom AD value is called a floating static route. A router uses it only when no other route with a lower AD value is available.
Now, let us add this link again. It brings the primary up. As soon as the primary route comes online, the router removes the backup route and adds the primary route again.

Видео Static and Floating Static routes configuration Explained | The ip route command | CCNA Video -8 канала ComputerNetworkingNotes