Whenever you’re planning to go the BSCI Examination and earn your CCNP certification, one of the greatest challenges is Mastering BGP. BGP is completely unique from any protocol you discovered to make your http://edition.cnn.com/search/?text=토토사이트 CCNA certification, and one of several dissimilarities is the fact BGP employs path characteristics to favor one route about An additional when many paths to or from a location exist.
Notice I mentioned “to or from”. In previously cost-free BGP tutorials, I talked over the BGP characteristics “pounds” and “local preference”. These characteristics are accustomed to favor one route into a location in excess of A different; by way of example, if BGP AS 100 has two paths to the destination in AS 200, these two attributes might be set in AS a hundred to favor a person path in excess of Yet another. But what if AS 100 wishes to inform the routers in AS 200 concerning which path it should really use to reach a offered location in AS 100?
That’s exactly where the BGP attribute “Multi-Exit Discriminator”, or MED, comes in. The MED worth may be set in AS a hundred to tell AS 200 which route it must use to reach a given community in AS a hundred.
As with lots of BGP characteristics, the MED is usually set which has a route-map. What you'll want to view is that there is no “established med” value in route maps. To change the MED of a path, you should alter the metric of that path. Permit’s say there are two entry paths for AS two hundred to make use of to reach destinations in AS a hundred. You need AS 200 to utilize the one hundred.one.one.0/24 path about the 100.2.2.0/24 path. First, determine the two paths with two independent ACLs.
R1(config)#entry-record 22 allow one hundred.1.one.0 0.0.0.255
R1(config)#obtain-list 23 allow a hundred.2.two.0 0.0.0.255
Subsequent, write a route-map that assigns a decreased metric to the greater-fascinating route.
R1(config)#route-map PREFER_PATH permit ten
R1(config-route-map)#match ip address 22
R1(config-route-map)#set metric one hundred
R1(config-route-map)#route-map PREFER_PATH permit twenty
R1(config-route-map)#match ip address 23
R1(config-route-map)#set metric 250
Eventually, utilize the route-map into the neighbor or neighbors.
R1(config-route-map)#router bgp one hundred
R1(config-router)#neighbor 22.two.2.2 route-map PREFER_PATH out
The important thing points to bear in mind is always that when a lot of BGP attributes desire an increased benefit, the MED is essentially an exterior metric – as well as a lower metric is desired, just as Along with the 안전놀이터 protocols you’ve presently examined to generate your CCNA certification.