View source for Mikrotik: BGP Dua Link main backup - dengan as-path PREPEND dan MD5 Authentication

[[File:Bgp-multihoming.png|center|900px|thumb]]

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

ISP2
 IP 192.168.2.1/24 - menuju ISP3
 IP 192.168.3.2/24 - menuju ISP1
 AS 20
 IP 10.10.10.0/24
 IP 10.10.20.0/24

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 


==Sambungan Fisik==

ISP1
 

 ISP1 ether0 -> ISP3 ether0
 ISP1 ether1 -> ISP2 ether1
 ISP2 ether0 -> ISP3 ether1
 
 ISP1 ether2 10.100.100.1/24
 ISP1 ether3 10.100.200.1/24
 
 ISP2 ether2 10.10.10.1/24
 ISP2 ether3 10.10.20.1/24
 
 ISP3 ether2 10.1.1.1/24
 ISP3 ether3 10.1.2.1/24



==Setup connection==

ISP1

 /ip address add interface=ether1 address=192.168.1.1/24
 /ip address add interface=ether2 address=192.168.3.1/24
 /ip address add interface=ether3 address=10.100.100.1/24
 /ip address add interface=ether3 address=10.100.200.1/24

ISP2

 /ip address add interface=ether1 address=192.168.2.1/24
 /ip address add interface=ether2 address=192.168.3.2/24
 /ip address add interface=ether3 address=10.10.10.1/24
 /ip address add interface=ether4 address=10.10.20.1/24

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

==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:

 #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 tcp-md5-key=$AP7i1
 add name=toISP3 remote-address=192.168.1.2 remote-as=30 tcp-md5-key=$AP7i1
 # 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

ISP2:

 #set our AS number
 /routing bgp instance set default as=20
 #add BGP peers
 /routing bgp peer
 add name=toISP1 remote-address=192.168.3.1 remote-as=10 tcp-md5-key=$AP7i1
 add name=toISP3 remote-address=192.168.2.2 remote-as=30 tcp-md5-key=$AP7i1
 #
 # advertize routing
 #
 /routing bgp network
 add network=10.10.10.0/24 synchronize=no
 add network=10.10.20.0/24 synchronize=no

ISP3:

 #set our AS number
 /routing bgp instance set default as=30
 #add BGP peers
 /routing bgp peer
 add name=toISP1 remote-address=192.168.1.1 remote-as=10 tcp-md5-key=$AP7i1
 add name=toISP2 remote-address=192.168.2.1 remote-as=20 tcp-md5-key=$AP7i1
 #
 # advertize routing
 #
 /routing bgp network
 add network=10.1.1.0/24 synchronize=no
 add network=10.1.2.0/24 synchronize=no

==Main/Backup link setup==

===ISP3===

Lakukan
* accept network kita sendiri
* drop semua tabel IP lainnya, karena kita tidak mau menjadi transit provider
* BGP AS prepend - menaikan AS path

 # setup routing filter
 #
 /routing bgp peer
 set toISP1 in-filter=isp1-in out-filter=isp1-out
 set toISP2 in-filter=isp2-in out-filter=isp2-out
 #
 # Outgoing filter ke ISP1:
 #
 /routing filter
 #accept our networks
 add chain=isp1-out prefix=10.1.1.0/24 action=accept
 add chain=isp1-out prefix=10.1.2.0/24 action=accept
 #discard the rest
 add chain=isp1-out action=discard
 #
 # Outgoing filter ke ISP2:
 #
 /routing filter
 #accept our networks and prepend AS path three times
 add chain=isp2-out prefix=10.1.1.0/24 action=accept set-bgp-prepend=3
 add chain=isp2-out prefix=10.1.2.0/24 action=accept set-bgp-prepend=3
 #discard the rest
 add chain=isp2-out action=discard
 # 
 # ISP1 menjadi main
 # ISP2 menjadi backup
 #
 /routing filter
 add chain=isp1-in action=discard
 add chain=isp2-in action=discard
 #
 /ip route
 add gateway=192.168.1.1 check-gateway=ping
 add gateway=192.168.2.1 distance=30 check-gateway=ping

==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

==Pranala Menarik==

* [[TCP/IP: Advanced Routing]]
* [[Quagga]]
* [[Mikrotik]]
* [[Cisco]]
* [[Juniper]]
* [[BIRD: Routing]]
* [[IPv6]]