Any time you’re preparing to pass the BSCI Examination and make your CCNP certification, considered one of the most significant difficulties is Mastering BGP. BGP is completely distinct from any protocol you discovered to gain your CCNA certification, and one of the dissimilarities is always that BGP utilizes path attributes to favor a single route over One more when a number of paths to or from a place exist.
Recognize I said “to or from”. In earlier totally free BGP tutorials, I talked over the BGP attributes “bodyweight” https://www.washingtonpost.com/newssearch/?query=먹튀검증 and “community desire”. These characteristics are accustomed to favor one particular path to the vacation spot above Yet another; for instance, if BGP AS one hundred has two paths into a vacation spot in AS 200, both of these characteristics is usually established in AS a hundred to favor a person route in excess of Yet another. But Imagine if AS one hundred needs to inform the routers in AS two hundred as to which route it really should use to succeed in a specified destination in AS 100?
That’s in which the BGP attribute “Multi-Exit Discriminator”, or MED, comes in. The MED price can be set in AS a hundred to tell AS two hundred which path it should use to achieve a offered network in AS one hundred.
As with several BGP attributes, the MED is often established with a route-map. What you have to watch is that there's no “set med” benefit in route maps. To alter the MED of the path, you might want to alter the metric of that path. Permit’s say that there are two entry paths for AS two hundred to make use of to achieve destinations in AS one hundred. You would like AS two hundred to make use of the a hundred.1.one.0/24 path more than the 100.2.two.0/24 path. Initial, determine the two paths with two separate ACLs.
R1(config)#obtain-checklist 22 allow one hundred.1.one.0 0.0.0.255
R1(config)#accessibility-record 23 안전놀이터 allow a hundred.two.two.0 0.0.0.255
Future, publish a route-map that assigns a lower metric to the more-desirable path.
R1(config)#route-map PREFER_PATH permit ten
R1(config-route-map)#match ip deal with 22
R1(config-route-map)#set metric a hundred
R1(config-route-map)#route-map PREFER_PATH permit 20
R1(config-route-map)#match ip tackle 23
R1(config-route-map)#set metric 250
Lastly, utilize the route-map on the neighbor or neighbors.
R1(config-route-map)#router bgp 100
R1(config-router)#neighbor 184.108.40.206 route-map PREFER_PATH out
The real key details to remember is usually that whilst numerous BGP characteristics want a higher worth, the MED is largely an external metric – along with a reduced metric is favored, equally as with the protocols you’ve currently examined to receive your CCNA certification.