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初期設定
iosv-0
en
terminal length 0
conf t
hostname iosv-0
line console 0
logging synchronous
exit
!
int lo0
ip address 1.1.1.1 255.255.255.255
!
int gi0/0
ip address 192.168.12.1 255.255.255.0
ip ospf 1 area 0
no shut
exit
!
router bgp 100
neighbor 192.168.23.3 remote-as 100
neighbor 192.168.23.3 update-source gi0/0
end
!
iosv-1
en
terminal length 0
conf t
hostname iosv-1
line console 0
logging sychronous
exit
!
int gi0/0
ip address 192.168.12.2 255.255.255.0
ip ospf 1 area 0
no shut
!
int gi0/1
ip address 192.168.23.2 255.255.255.0
ip ospf 1 area 0
no shut
exit
!
iosv-2
en
terminal length 0
conf t
hostname iosv-2
line console 0
logging synchronous
exit
!
int lo0
ip address 3.3.3.3 255.255.255.255
!
int gi0/0
ip address 192.168.23.3 255.255.255.0
ip ospf 1 area 0
no shut
exit
!
router bgp 100
neighbor 192.168.12.1 remote-as 100
neighbor 192.168.12.1 update-source gi0/0
end
!
transport connection-mode passive
iosv-0(config-router)#neighbor 192.168.12.2 transport connection-mode passive
iosv-1(config-router)#neighbor 192.168.12.2 transport connection-mode passive
iosv-0(config-router)#do sh ip bgp sum | b activity
BGP activity 12/10 prefixes, 13/12 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
192.168.12.2 4 100 0 0 1 0 0 00:00:28 Idle
192.168.23.3 4 200 0 0 1 0 0 never Idle両方passiveにするとピアリングできない（そらそう）。
iosv-0(config-router)#neighbor 192.168.12.2 transport connection-mode active
iosv-0(config-router)#do sh ip bgp sum
BGP activity 13/11 prefixes, 14/12 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
192.168.12.2 4 100 5 5 3 0 0 00:00:09 1
192.168.23.3 4 200 0 0 1 0 0 never Idle片方activeにするとピアリングできる（そらそう）。
とりたてて難しい話ではないけれども、トラブルシューティングの手札として覚えておく。