Table of Contents
What is backup static route?
A floating static route is used as a backup route. It has a manually configured administrative distance greater than that of the primary route and therefore would not be in the routing table until the primary route fails. You will test failover to the backup route, and then restore connectivity to the primary route.
What is the administrative distance of a static route?
1
Static routes have a default administrative distance of 1. A router prefers a static route to a dynamic route because the router considers a route with a low number to be the shortest.
What is the default administrative distance for a static route to a next hop address?
By default, OSPF has a default administrative distance of 110 and RIP has a default administrative distance of 120….Cisco.
| Routing protocol | Administrative distance |
|---|---|
| Next Hop Resolution Protocol (NHRP) | 250 |
| Default static route learned via DHCP | 254 |
| Unknown and unused | 255 |
What is the administrative distance of BGP routes?
Routing protocols with lower administrative distances are given priority over routing protocols with higher administrative distances. EBGP has an administrative distance of 20. OSPF has an administrative distance of 110.
What is back door in BGP?
The term “backdoor” is a very controversial term when it comes to privacy and security. However, when it comes to BGP, it is a well-known feature that is used to change the administrative distance of eBGP in order for an interior gateway routing protocol (IGP) to take precedence over an eBGP route.
What is the main advantage of static routes?
Static routing provides some advantages over dynamic routing, including: Static routes are not advertised over the network, resulting in better security. Static routes use less bandwidth than dynamic routing protocols, as routers do not exchange routes. No CPU cycles are used to calculate and communicate routes.
What are the disadvantages of static route?
The disadvantages of static routing include:
- They are not easy to implement in a large network.
- Managing the static configurations can become time consuming.
- If a link fails, a static route cannot reroute traffic.
Which routing protocol has the most preferable administrative distance?
EIGRP has an administrative distance of 90, whereas RIP has an administrative distance of 120. Therefore, EIGRP is deemed more trustworthy than RIP. Table 11.1. Cisco default administrative distances.
How does BGP choose the best path?
BGP Table path selection
- Prefer the highest local-preference value.
- Prefer the shortest AS-path length.
- Prefer the lowest origin value.
- Prefer the lowest MED value.
- Prefer routes learned from an EBGP peer over an IBGP peer.
- Prefer best exit from AS.
- For EBGP-received routes, prefer the current active route.
Does static route override OSPF?
By default, static route has an admin distance of 10 and OSPF Int and OSPF Ext have admin distances of 30 and 110 respectively. To set OSPF to take precedence over the static route, increase the admin distance of the static route accordingly, depending upon the route being an OSPF external or OSPF internal.
What are two advantages of static routing over dynamic?
Static routing is more secure because it does not advertise over the network. Static routing scales well with expanding networks. Static routing requires very little knowledge of the network for correct implementation. Static routing uses fewer router resources than dynamic routing.
What is a backup static default route in BGP?
The backup static default route is the only remaining default route. Therefore, the router will install the floating default route into its routing table, and subsequently redistribute it into the IGP. The backup edge router of the ISP can also use floating static routes, which are redistributed into the ISP BGP process.
Can the backup Edge router of the ISP use floating static routes?
The backup edge router of the ISP can also use floating static routes, which are redistributed into the ISP BGP process. 5-34 Configuring BGP on Cisco Routers (BGP) v3.1 Copyright © 2004, Cisco Systems, Inc.
What is the difference between the backup Edge Router and IGP?
The backup edge router is also redistributing the default route into the IGP. However, the static route that is used is a floating static route, which is assigned a high administrative distance (AD), higher than the AD of the customer IGP.
How to have backup routes using static routing?
So to summarize, if you want to have backup routes using static routing, you can play with Administrative distance of the static routes. This is all I have for you in this article, if you have any question just leave it in the comment part.