Once you’re making ready to move the BSCI Test and gain your CCNP certification, one of the greatest challenges is Understanding BGP. BGP is totally various from any protocol you discovered to get paid your CCNA certification, and one of the variances is always that BGP makes use of path attributes to favor a single path more than another when a number of paths to or from the location exist.
See I mentioned “to or from”. In before cost-free BGP tutorials, I discussed the BGP characteristics “pounds” and “neighborhood choice”. These characteristics are accustomed to favor a single path to the location over Yet another; as an example, if BGP AS a hundred has two paths to some destination in AS two hundred, both of these attributes might be established in AS a hundred to favor one route over A different. But Imagine if AS a 메이저사이트 hundred would like to inform the routers in AS 200 as to which route it ought to use to succeed in a offered vacation spot in AS one hundred?
That’s where the BGP attribute “Multi-Exit Discriminator”, or MED, comes in. The MED benefit may be set in AS 100 to inform AS two hundred which route it really should use to achieve a given network in AS one hundred.
As with many BGP attributes, the MED is often established using a route-map. What you should enjoy is that there's no “established med” worth in route maps. To alter the MED of a route, you must change the metric of that path. Let’s say there are two entry paths for AS 200 to employ to reach Places in AS 100. You wish AS two hundred to use the 100.1.one.0/24 path in excess of the 100.two.two.0/24 route. Initially, detect the two paths with two separate ACLs.
R1(config)#accessibility-checklist 22 allow one hundred.one.1.0 0.0.0.255
R1(config)#access-record 23 permit one hundred.two.two.0 0.0.0.255
Up coming, create a route-map that assigns a reduced metric to the more-appealing path.
R1(config)#route-map PREFER_PATH allow 10
R1(config-route-map)#match ip deal with 22
R1(config-route-map)#set metric one hundred
R1(config-route-map)#route-map PREFER_PATH allow 20
R1(config-route-map)#match ip handle 23
R1(config-route-map)#established metric 250
Ultimately, apply the route-map into the neighbor or neighbors.
R1(config-route-map)#router bgp one hundred
R1(config-router)#neighbor 22.2.two.two route-map PREFER_PATH out
The crucial element factors to bear in mind is although numerous BGP characteristics http://edition.cnn.com/search/?text=토토사이트 prefer the next benefit, the MED is basically an exterior metric – along with a decreased metric is preferred, equally as With all the protocols you’ve by now studied to make your CCNA certification.