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BGP

12

BGP .

Merion Academy


 BGP

BGP:

  1. BGP
  2. BGP
  3. BGP
  4. NLRI BGP

BGP

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1: BGP

ATL1(config)#router bgp 200
ATL1( config-router)#neiqhbor 10.30.30.5 remote-as 200    
ATL1( config-router)#neiqhbor 10.30.30.5 update- source lo0 
ATL1( config= router)#neiqhbor 10.30 .30.5 password S34Dfr112s1WP 
ATL1(config-router)#neiqhbor 10.40.40.4 remote-as 200
ATL1( config-router)#neiqhbor 10.40.40 .4 update- source lo0
ATL1(config-router)#neiqhbor 10.40.40.4 password S34Dfr112s1WP

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2: BGP

ATL2 (config)#router bgp 200
ATL2 (config-router)#neighbor MYPEERGR1 peer-group
ATL2 (config-router)#neighbor MYPEERGR1 remote-as 200 
ATL2 (config-router)#neighbor MYPEERG1l update-source lo0 
ATL2(config-router)#neighbor MYPEERGRl next-hop-self
ATL2 (config-router)#neighbor 10.40.40 .4 peer-group MYPEERGR1
ATL2 (config-router)#neighbor 10.50.50 .5 peer-group MYPEERGR1

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3: BGP

ATL2#conf t
Enter configuration commands, one per line. End with CNTL/Z. 
ATL2 (config)#router bgp 200
ATL2 (config-router)#template peer- session MYNAME
ATL2 (config-router-stmp)#inherit peer- session MYOTHERNAME
ATL2 (config- router-stmp )#remote-as 200
ATL2(config-router-stmp )#password MySecrectPass123
ATL2 (config-router-stmp )#exit-peer-session
ATL2 (config-router)#neiqhbor 10.30.30 .10 inherit peer-session MYNAME
ATL2 (config-router)#end
ATL2#

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4 BGP.

4: BGP

ATL2#conf t
Enter configuration commands, one per line. End with CNTL/Z. 
ATL2 (config)#router bgp 200
ATL2(config-router)#template peer-policy MYPOLICYNAME
ATL2 (config-router-ptmp )#next-hop-self
ATL2 (config-router-ptmp )#route-map MYMAP out
ATL2 (config-router-ptmp )#allowas-in
ATL2 (config-router-ptmp )#exit-peer-policy
ATL2 (config-router)#neighbor 10.40.40.10 remote-as 200
ATL2 (config-router)#neighbor 10.40.40.10 inherit peer-policy MYNAME
ATL2 (config-router)#end 
ATL2#

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(split-horizon rule) IBGP, , IBGP. router reflector.

. 1: router reflector

  router reflector

router reflector , router reflector (R3). route reflector R4, R5 R6. IBGP R3 . 5 router reflector. , router reflector.

5: BGP ROUTE REFLECTOR

R3#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
 R3 (config)#router bgp 200
R3 (config-router)#neighbor 10.50.50.10 remote -as 200
R3 (config-router)#neighbor 10.50.50.10 route-reflector-client
R3 (config-router)#end	
R3#		

Route reflector (ID) , , route reflector. Cisco . 32- , BGP route reflector.

Route reflector , IBGP. , Route reflector (, R4), R3 (R5 R6), (R1 R2). , IBGP , .

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6 BGP.

R3#configure terminal
Enter configuration commands, one per line. End with CNTL/Z. 
R3 (config)#router bgp	65501
R3(config-router)#bgp confederation identifier 100
R3 (config-router)#bgp confederation peers 65502
R3 (config-router)#neighbor 10 .20.20.1 remote-as 65502
R3 (config-router)#end 
R3#

. , , (community). , , . 32- ( ), , .

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. :

  • Decimal - 0 to 4294967200 ( )
  • Hexadecimal 0x0 to 0xffffffa0 ( )

:

  • AA:NN

AA - 16- , AS, 16- , AS. , AS 100 100:101, 101- , .

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  • No-export - AS. , AS. ( AS) .
  • Local-AS - AS
  • No-advertise -

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  • 65535:4294967295

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7: BGP

R3#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
R3(config)#ip prefix-list MYLIST permit 172.16.0.0/16 le 32
R3(config)#route-map SETCOMM permit 10
R3(config-route-map)#match ip address prefix-list MYLIST
R3(config-route-map)#set community no-export
R3(config-route-map)#route-map SETCOMM permit 20
R3(config)#router bgp 100
R3(config-router)#neighbor 10.20.20.1 route-map SETCOMM out
R3 (config-router)#neighbor 10.20.20.1 send-community
R3(config-router)#end
R3#

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