Mikrotik: IPSec VPN with Dynamic Routing / Mikrotik and Cisco
https://wiki.mikrotik.com/wiki/IPSec_VPN_with_Dynamic_Routing_/_Mikrotik_and_Cisco
This example shows how to setup an IPSec VPN using dynamic routing protocol (RIP), it can be used with another protocol. In this example you can find a setup between Mikrotik and Cisco routers, but it can be done just between Mikrotik routers, but to be more colorfull I decided to use Mikrotik and Cisco. Below are the steps to complete the configuration of IPSec VPN with Dynamic Routing.
Mikrotik RouterOS
If you are using ROS v3.x or above, be sure to check the end of this list to see a list of necessary mod.
First should configure a Tunnel Interface:
/ interface ipip add name="Tunnel1" mtu=1480 local-address=10.10.1.100 remote-address=10.10.1.200 comment="" disabled=no
After that all interfaces are configured, than should asign IP addresses for interfaces:
/ ip address add address=10.10.1.100/24 network=10.10.1.0 broadcast=10.10.1.255 interface=WAN comment="" disabled=no add address=192.168.1.1/24 network=192.168.1.0 broadcast=192.168.1.255 interface=LAN comment="" disabled=no add address=172.16.0.1/30 network=172.16.0.0 broadcast=172.16.0.3 interface=Tunnel1 comment="" disabled=no
Enable Routing in Mikrotik Router, in this case RIP:
/ routing rip set redistribute-static=no redistribute-connected=no redistribute-ospf=no redistribute-bgp=no metric-static=1 \ metric-connected=1 metric-ospf=1 metric-bgp=1 update-timer=30s timeout-timer=3m garbage-timer=2m / routing rip interface add interface=Tunnel1 receive=v2 send=v2 authentication=none authentication-key="" prefix-list-in="" prefix-list-out="" / routing rip neighbor add address=172.16.0.2 / routing rip network add address=192.168.1.0/24 add address=172.16.0.0/30
In v3.x the bolded line will change on:
/ routing rip interface add interface=Tunnel1 receive=v2 send=v2 authentication=none authentication-key="" in-prefix-list="" out-prefix-list=""
IPSec setup, here should be defined the ipsec policy, peer and proposal. Make sure that policy should not have enabled option tunnel, in this case tunel should be set to NO, because it will be used the transport mode of IPSec not the tunnel mode:
/ ip ipsec proposal add name="IPSec" auth-algorithms=md5 enc-algorithms=3des lifetime=30m lifebytes=0 pfs-group=modp1024 disabled=no / ip ipsec peer add address=10.10.1.200 secret="ipsec" generate-policy=no exchange-mode=main send-initial-contact=yes \ proposal-check=obey hash-algorithm=md5 enc-algorithm=3des dh-group=modp1024 lifetime=1d lifebytes=0 disabled=no / ip ipsec policy add src-address=10.10.1.100/32:any dst-address=10.10.1.200/32:any protocol=all action=encrypt level=require \ ipsec-protocols=esp tunnel=no sa-src-address=10.10.1.100 sa-dst-address=10.10.1.200 \ proposal=IPSec manual-sa=none dont-fragment=clear disabled=no
In v3.x the bolded line will change on:
/ ip ipsec proposal add name="IPSec" auth-algorithms=md5 enc-algorithms=3des lifetime=30m pfs-group=modp1024 disabled=no / ip ipsec peer add address=10.10.1.200/32:500 secret="ipsec" generate-policy=no exchange-mode=main send-initial-contact=yes \ proposal-check=obey hash-algorithm=md5 enc-algorithm=3des dh-group=modp1024 lifetime=1d lifebytes=0 disabled=no / ip ipsec policy add src-address=10.10.1.100/32:any dst-address=10.10.1.200/32:any protocol=all action=encrypt level=require \ ipsec-protocols=esp tunnel=no sa-src-address=10.10.1.100 sa-dst-address=10.10.1.200 \ proposal=IPSec manual-sa=none disabled=no
Cisco IOS
Cisco Interfaces and addresses:
FastEthernet 0/0 description *** WAN *** ip address 10.10.1.200 255.255.255.0 crypto map vpn
FastEthernet 0/1 description *** LAN *** ip address 192.168.2.1 255.255.255.0
Cisco Tunnel Interface:
interface Tunnel1 description **Cisco Peer** ip address 172.16.0.2 255.255.255.252 no ip redirects no ip unreachables no ip proxy-arp ip mtu 1480 ip rip v2-broadcast ip tcp adjust-mss 1400 load-interval 30 tunnel source 10.10.1.200 tunnel destination 10.10.1.100 tunnel mode ipip hold-queue 1024 in hold-queue 1024 out
Routing in Cisco:
router rip version 2 timers basic 30 60 90 90 redistribute connected metric 1 route-map connected-to-rip redistribute static metric 5 route-map static-to-rip network 172.16.0.2 network 192.168.2.0 distribute-list prefix LAN out no auto-summary
Setup the prefix-list to match the Local subnet:
ip prefix-list LAN seq 10 permit 192.168.2.0/24
Setup route-maps to match interfaces to be advertised by RIP:
route-map connected-to-rip permit 10 match interface FastEthernet0/0 ! route-map static-to-rip permit 10 match ip address prefix-list LAN
IPSec and Crypto setup in Cisco, also here trasnport mode of IPSec should be setup:
! crypto isakmp policy 1 encr 3des hash md5 authentication pre-share group 2 ! crypto isakmp key ipsec address 0.0.0.0 0.0.0.0 ! crypto ipsec security-association idle-time 600 ! crypto ipsec transform-set vpn esp-3des esp-md5-hmac mode transport ! crypto map vpn 1 ipsec-isakmp description **To Mikrotik Peer** set peer 10.10.1.100 set transform-set vpn set pfs group2 match address mikrotik_peer !
Setup access-list to match the IPSec peer:
ip access-list extended mikrotik_peer permit ipinip host 10.10.1.200 host 10.10.1.100
Type this in "enable" mode to view your routing table (after succesfull RIP update):
sh ip route
or
sh ip rip database
This example can be implemented also with another routing protocol like OSPF, and also very simply we can setup here a failover connection. Regarding the failover, the setup is very easy, all that we need is to create another set of tunnels via another ISP or gateway, but again the remote peer is the same router. Instead of the routing protocol for the second set of tunnels, it needs static routes to be configured, only that the static routes should have higher distance than the dynamic protocol. The idea is that, when the primary link will go down (dynamic routing distance=120) than the backup link becomes active (static routes distance=200), as soon as the primary link will come up, it will put the failover link in inactive mode.Titolo del collegamento