BGP over dynamic IPsec

The following example shows how to create a dynamic IPsec VPN tunnel that allows BGP.

Configuring IPsec on FortiGate 1

1. Go to Policy & Objects > Addresses and select create new Address.

2. Create an Address Group.

3. Go to Dashboard and enter the CLI Console widget.
4. Create phase 1:

config vpn ipsec phase1-interface

edit Dialup

set type dynamic set interface wan1 set mode aggressive set peertype one set mode-cfg enable set proposal 3des-sha1 aes128-sha1 set peerid dial set assign-ip disable set psksecret

next

end

5. Create phase 2:

config vpn ipsec phase2-interface

edit dial_p2

set phase1name Dialup set proposal 3des-sha1 aes128-sha1 set src-addr-type name set dst-addr-type name set src-name all set dst-name VPN_DST

next

end

Configuring BGP on FortiGate 1

1. Go to Network > Interfaces and create a Loopback interface.
2. Set IP/Network Mask to 20.20.20/255.255.255.255.
3. Go to Dashboard and enter the CLI Console widget.
4. Create a BGP route.

config router bgp set as 100 set router-id 1.1.1.1 config neighbor edit 10.10.10.10 set ebgp-enforce-multihop enable set remote-as 200 set update-source loop

next

end

config redistribute connected set status enable

end

end

Adding policies on FortiGate 1

1. Go to Policy & Objects > IPv4 Policy and create a policy allowing BGP traffic from Dialup to loop interfaces. 2. Go to Policy & Objects > IPv4 Policy and create a policy allowing BGP traffic from loop to Dialup interfaces.

Configuring IPsec on FortiGate 2

1. Go to Dashboard and enter the CLI Console widget.
2. Create phase 1:

config vpn ipsec phase1-interface edit Dialup set interface wan1 set mode aggressive set mode-cfg enable

set proposal 3des-sha1 aes128-sha1 set localid dial set remote-gw 172.20.120.22 set assign-ip disable set psksecret

next

end

3. Create phase 2:

config vpn ipsec phase2-interface edit dial_p2 set phase1name Dialup set proposal 3des-sha1 aes128-sha1 set keepalive enable next

end

Configuring BGP on FortiGate 2

1. Go to Network > Interfaces and create a Loopback interface.
2. Set IP/Network Mask to 10.10.10/255.255.255.255.
3. Go to Dashboard and enter the CLI Console
4. Create a BGP route.

config router bgp set as 200 set router-id 1.1.1.2 config neighbor edit 20.20.20.20 set ebgp-enforce-multihop enable set remote-as 100 set update-source loop

next

end

config redistribute connected set status enable

end

end

Adding policies on FortiGate 2

1. Go to Policy & Objects > IPv4 Policy and create a policy allowing BGP traffic from Dialup to loop
2. Go to Policy & Objects > IPv4 Policy and create a policy allowing BGP traffic from loop to Dialup

Adding a static route on FortiGate 2

Go to Network > Static Routes and add a route to the remote Loopback interface via Dialup interface.

Verifying the tunnel is up

Go to Monitor > IPsec Monitor to verify that the tunnel is Up.

Results

1. From FortiGate 1, go to Monitor > Routing Monitor and verify that routes from FortiGate 2 were successfully advertised to FortiGate 1 via BGP.
2. From FortiGate 1, go to Dashboard.
3. Enter the CLI Console widget and type this command to verify BGP neighbors:

get router info bgp summary

4. From FortiGate 2, go to Monitor > Routing Monitor and verify that routes from FortiGate 1 were successfully advertised to FortiGate 2 via BGP.
5. From FortiGate 2, go to Dashboard.
6. Enter the CLI Console widget and type this command to verify BGP neighbors:

get router info bgp summary