Once you’re preparing to go the BSCI Examination and get paid your CCNP certification, amongst the largest issues is Studying BGP. BGP is totally distinctive from any protocol you discovered to earn your CCNA certification, and one of several dissimilarities is always that BGP takes advantage of path characteristics to favor a person route in excess of One more when many paths to or from the desired destination exist.
See I claimed “to or from”. In before cost-free BGP tutorials, I talked about the BGP characteristics “pounds” and “regional desire”. These characteristics are used to favor a person path to your place around A different; as an example, if BGP AS one hundred has two paths to a desired destination in AS two hundred, these two characteristics might be established in AS 100 to favor just one route 트랜드판 around Yet another. But Imagine if AS 100 wants to tell the routers in AS 200 regarding which route it should really use to reach a provided vacation spot in AS a hundred?
That’s in which the BGP attribute “Multi-Exit Discriminator”, or MED, comes in. The MED value is usually set in AS 100 to tell AS two hundred which path it must use to achieve a specified network in AS one hundred.
Just like many BGP characteristics, the MED could be set which has a route-map. What you need to watch is that there is no “established med” value in route maps. To alter the MED of a path, you have to alter the metric of that path. Enable’s say https://www.washingtonpost.com/newssearch/?query=토토사이트 that there are two entry paths for AS 200 to employ to achieve Locations in AS a hundred. You'd like AS two hundred to make use of the 100.1.one.0/24 route over the a hundred.two.two.0/24 path. First, detect the two paths with two individual ACLs.
R1(config)#obtain-list 22 permit one hundred.one.1.0 0.0.0.255
R1(config)#obtain-list 23 allow one hundred.2.two.0 0.0.0.255
Up coming, generate a route-map that assigns a decreased metric to the greater-fascinating path.
R1(config)#route-map PREFER_PATH permit ten
R1(config-route-map)#match ip deal with 22
R1(config-route-map)#established metric a hundred
R1(config-route-map)#route-map PREFER_PATH allow 20
R1(config-route-map)#match ip address 23
R1(config-route-map)#established metric 250
Ultimately, apply the route-map to your neighbor or neighbors.
R1(config-route-map)#router bgp one hundred
R1(config-router)#neighbor 22.2.2.two route-map PREFER_PATH out
The true secret factors to keep in mind is that though quite a few BGP characteristics desire a better benefit, the MED is basically an external metric – plus a lessen metric is preferred, just as Along with the protocols you’ve now researched to gain your CCNA certification.