BGP OSPF Questions: Difference between revisions

= BGP =

 

*If we turned on the synchronisation BGP router will not advertize the route learned from IBGP PEER to EBGP Peer unless that route is learned through IGP.

*Split horizon rule -Routes larn though IBGp nei will not be advertized to other IBGP nei .

but on the intraconfedration EBGP session parmaters for IBGP are still preserved. (like next hop self, metric, preference)

 

 

*MED Vs AS path prepend - MED doesnot goes beyond neibor As while As path prepeend goes beyond that.

bgp dmzlink-bw

neighbor ip-address dmzlink-bw

 

*Aggreagate with AS set command - normal aggregation with summary command advertise the summary prefix only and suppress all the specific routes, so router which is performing the aggreagation will include its own AS while sending the update.

 

*Attribute map -can be used to modify the community received in aggregation router to none.(command) MAP. When particular is sending the prefix to router performing aggregation with community like no export attached, Aggregate router will inherit the communtiy and can cause issue to aggregate prefix while propagating, To avoid it we can modifiy the community to none using atrribute map command (aggrgate address x.x.x.x .x.x.x as-set summary only attribute map)

 

*BGP Backdor link - used to modifiy the AD for external route from 20 to 200 so that IGP learned route can be prefered over EBGP.