Mikrotik: BGP 2 BGP redistribute 2 OSPF
Ada tiga (3) ISP
ISP1:
IP 192.168.1.1/24 menuju ISP3 IP 192.168.3.1/24 menuju ISP2 AS 10 IP 10.100.100.0/24 IP 10.100.200.0/24
ISP3 (kita)
IP 192.168.1.2/24 - menuju ISP1 IP 192.168.2.2/24 - menuju ISP2 AS 30 IP 10.1.1.0/24 IP 10.1.2.0/24
R4
IP 10.1.1.2/24 menuju ISP3 IP 172.16.1.1 menuju R5 IP 172.16.10.1 LAN IP 172.16.20.1 LAN
R5
IP 10.1.2.2/24 menuju ISP3 IP 172.16.1.2 menuju R4 IP 172.16.100.1/24 LAN IP 172.16.200.1/24 LAN
Sambungan Fisik
ISP1
ISP1 Eth1/0 -> ISP3 Eth1/0 ISP1 Eth1/1 -> ISP2 Eth1/1 ISP2 Eth1/0 -> ISP3 Eth1/1 ISP1 Eth1/2 10.100.100.1/24 ISP1 Eth1/3 10.100.200.1/24 ISP2 Eth1/2 10.10.10.1/24 ISP2 Eth1/3 10.10.20.1/24 ISP3 Eth1/2 10.1.1.1/24 ISP3 Eth1/3 10.1.2.1/24
Setup connection
ISP1
/ip address add address=192.168.1.1/24 interface=ether1 /ip address add address=192.168.3.1/24 interface=ether2 /ip address add address=10.100.100.1/24 interface=ether3 /ip address add address=10.100.200.1/24 interface=ether4
ISP3
/ip address add interface=ether1 address=192.168.1.2/24 /ip address add interface=ether2 address=192.168.2.2/24 /ip address add interface=ether3 address=10.1.1.1/24 /ip address add interface=ether4 address=10.1.2.1/24
R4
/ip address add interface=ether1 address=10.1.1.2/24 /ip address add interface=ether2 address=172.16.1.1/24 /ip address add interface=ether3 address=172.16.10.1/24 /ip address add interface=ether4 address=172.16.20.1/24
R5
/ip address add interface=ether1 address=10.1.2.2/24 /ip address add interface=ether2 address=172.16.1.2/24 /ip address add interface=ether3 address=172.16.100.1/24 /ip address add interface=ether4 address=172.16.200.1/24
BGP Peering
Consider that IP connectivity between ISPs edge routers and Our Core router is already set up and working properly. So we can start to establish BGP peering to both ISPs.
ISP1:
enable
configure terminal
router bgp 10
bgp router-id 192.168.1.1
network 10.100.100.0 mask 255.255.255.0
network 10.100.200.0 mask 255.255.255.0
neighbor 192.168.1.2 remote-as 30
end
#set our AS number /routing bgp instance set default as=10 #add BGP peers /routing bgp peer # add name=toISP2 remote-address=192.168.3.2 remote-as=20 add name=toISP3 remote-address=192.168.1.2 remote-as=30 # jika ingin redistribute default route ke client yang spesifik # add name=toISP2 remote-address=192.168.3.2 remote-as=20 default-originate=if-installed # add name=toISP3 remote-address=192.168.1.2 remote-as=30 default-originate=if-installed # # advertize routing # /routing bgp network add network=10.100.100.0/24 synchronize=no add network=10.100.200.0/24 synchronize=no
Main / Backup Link Setup di ISP3
Lakukan
- accept network kita sendiri
- drop semua tabel IP lainnya, karena kita tidak mau menjadi transit provider
- BGP AS prepend - menaikan AS path ke salah satu ISP (disini ISP1)
ISP3:
enable
configure terminal
router bgp 30
bgp router-id 192.168.1.2
no synchronization
bgp log-neighbor-changes
network 10.1.1.0 mask 255.255.255.0
network 10.1.2.0 mask 255.255.255.0
neighbor 192.168.1.1 remote-as 10
redistribute ospf 3 metric 100
end
OSPF
ISP3
enable configure terminal ! ! area 0 = backbone router ospf 3 network 10.1.1.0 0.0.0.255 area 0.0.0.0 network 10.1.2.0 0.0.0.255 area 0.0.0.0 end
R4
enable configure terminal ! ! area 0 = backbone router ospf 4 network 10.1.1.0 0.0.0.255 area 0.0.0.0 network 172.16.1.0 0.0.0.255 area 0.0.0.0 network 172.16.10.0 0.0.0.255 area 0.0.0.0 network 172.16.20.0 0.0.0.255 area 0.0.0.0 end
R5
enable configure terminal ! ! area 0 = backbone router ospf 5 network 10.1.2.0 0.0.0.255 area 0.0.0.0 network 172.16.1.0 0.0.0.255 area 0.0.0.0 network 172.16.100.0 0.0.0.255 area 0.0.0.0 network 172.16.200.0 0.0.0.255 area 0.0.0.0 end
Cek
/routing filter print /routing bgp instance print /routing bgp peer print status /routing bgp peer print /routing bgp advertisements print /ip route print
Referensi
- https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_bgp/configuration/xe-16/irg-xe-16-book/configuring-a-basic-bgp-network.html
- https://wiki.mikrotik.com/wiki/Manual:Simple_BGP_Multihoming