In networking, a default route is the best way to make sure that packets destined for a particular host reach their destination. Routers use routing tables to keep track of which hosts should receive which packets. If a router doesn’t have information about a route, it will use a default route. The default route usually points to the router itself. In this blog post, we will explore the question of whether or not can be issued on router R2 to verify the propagation of a static default route from R1 to R2.?
If you want to verify that the default route on router R is propagating out to router R, you can issue a static route on router R. This route will be configured as the default route for network N. To do this, use the following command:
R1(config)#ip route 0.0.0.0 0.0.0.0 192.168.1.1
R1 and R2
The answer to this question depends on the configuration of the routers. If both routers have a static default route pointing to R1, then the answer is yes. Conversely, if only Router R has a static default route pointing to R1, then the answer is no; that router will not be able to verify that the default route propagates from R1 to R2.
The Default Router
The default router can be issued on a router R to verify the propagation of a static default route from R to R. When you establish a static default router on R, packets that are destined for any destination outside the router’s local network are forwarded through the router. The following example shows how to set up a static default route on Router R:
Router#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)#router static ip default-route 10.0.0.1 Router(config)#end Router#
In this configuration, Router R has configured a static default route which points to the IP address 10.0.0.1. If you want to verify that the static default route is propagating through the network, you can use the show ip routes command on Router R:
Router#show ip routes Codes: L – local , C – connected , S -static , O – ospf , I – IS-IS , B – BushfireTalk Default Gateway: 10.0.0.1 Primary DNS Server: 220.127.116.11 Secondary DNS Server: 8.8 .4 .4
Verifying Default Route Propagation
Default route propagation is an important topic to understand and verify for any routing configuration. Default route propagation can be verified on router R by issuing the following command:
Router R# show ip route
Codes: C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
Network Next-hop Interface Metric Propagation Type Route 18.104.22.168/24 10.10.10.2 0 Static 22.214.171.124/16 10.10.10.1 0 BGP
Routers R and S are both connected to each other, and both routers have received the same routing information from their upstream routers. Router R has also propagated a default route to router S.
What Is a Static Default Router?
A static default route is a default route that is manually configured on a router. A static default route can be used to verify the propagation of a static default route from one router to another.
How Does a Static Default Route Work?
A static default router is a routing protocol instruction that tells a router to send all packets destined for a certain destination network (the Default Gateway) via the same path. Static routers can be issued on routers in either local or external routing contexts.
When you create or configure a static default router on an interface, the router uses this information to direct packets destined for any destination host connected to that interface through the Default Gateway. If you want to verify whether a static default router has propagated from your router to another router, you can use the show ip route command. The output of this command will list each active static route and its respective metric values. If a static default route exists and has been configured on both routers, the two routers will have different metrics because their routes will go through different gateways.
Can You Issue a Static Default Route on Router R2?
As a network administrator, you may have wondered if it’s possible to issue a static default route on router R2 to verify the propagation of a static default route from R to R. The answer is yes, you can issue a static default route on router R2.
First, determine the IP addresses that need to be routed through router R2. For example, the IP address of server S1 will be 192.168.1.1 and the IP address of server S2 will be 192.168.2.1. Next, issue the following commands on router R2:
Router(config)#ip route 0.0.0.0 0.0.0.0 192.168.1.1
Router(config)#ip route 0.0.0.0 0.0.0.255 192\.168\.1\[masklen] Router(config)#ip default-gateway 192\.168\.1\[masklen]
In this article, we are going to explore the possibility of issuing a router R2 to verify the propagation of a static default route from R1 to R2. We will be using the same network diagram that was used in our previous article on verifying the propagation of a static route. Before we move on, it is important to mention that this article is not intended for experienced users and is meant for those who are new to Cisco RouterOS configuration and troubleshooting. So if you’re not sure whether or not you can handle trying some of the more complicated commands, I would recommend that you skip this article and come back later when you have a bit more experience under your belt.