Hi guys,
I’m completely new to this Mikrotik stuff. I purchased a RouterBOARD 1000 with RouterOS on it as well as a current Level-6 license to see if it can do what I want them to do. The RouterBOARD runs Version 3.10 of RouterOS and the Level-6 License is the latest Version 3.16. In the first step, I want to setup the following:
+--------------+ +-------+ +-------+ +--------------+
| Customer/ | <--- Ethernet Link ---> | L2TP/ | <==========> | L2TP/ | <--- Ethernet Link ---> | PPPoE Server |
| PPPoE Client | | LAC | | LNS | +--------------+
+--------------+ +-------+ +-------+
The customers have an ethernet connection to the LAC, which in turn got a connection to the internet and got a public IP address. The LNS resides on a data center and also has got a public IP, so they can reach each other using standard IP communication. Similar setups were already discussed in http://forum.mikrotik.com/t/pppoe-over-l2tp/16123/1 and http://forum.mikrotik.com/t/bcp-in-3-0beta10-sample-config/14516/1 but finally without providing a solution or configuration example. Now, I’ll try to do it here…
After getting the above working, the second step would be to aggregate two or more ISP-links (between LAC and LNS) for the L2TP tunnel to get a cheap broadband link. At the moment the LAC is the RouterBOARD 1000 and the LNS a dedicated server running RouterOS.
The third and last step will be to add traffic prioritization to make this setup capable of handling VoIP regardless of bandwidth consumption. But that’s another story, I think. 
Currently my setup on the LNS looks like this:
/ip address add interface=ether1 address=192.168.0.210 netmask=255.255.255.0
/interface bridge add name=lns_bridge0
/interface bridge port add bridge=lns_bridge0 interface=ether2
/ppp profile add name=noipaddr bridge=lns_bridge0
/ppp secret add name=lac_user1 password=secret profile=noipaddr service=l2tp
/interface l2tp-server server set enabled=yes
/interface l2tp-server add user=lac_user1
And on the LAC:
/ip address add interface=ether1 address=192.168.0.211 netmask=255.255.255.0
/interface bridge add name=lac_bridge0
/interface bridge port add bridge=lac_bridge0 interface=ether2
/ppp profile add name=noipaddr bridge=lac_bridge0
/interface l2tp-client add connect-to=192.168.0.210 user=lac_user1 password=secret profile=noipaddr disabled=no
The LAC has the IP address 192.168.0.211 and the LNS gets the IP address 192.168.0.210, later this IP addresses could be the one assigned by the local ISP where the LAC resides and the public IP of the LNS in the data center.
The connection seems to work; on the LAC:
/interface l2tp-client monitor l2tp-out1
status: "connected"
uptime: 3m7s
idle-time: 38s
mtu: 1460
mru: 1460
/interface bridge port print
Flags: X - disabled, I - inactive, D - dynamic
# INTERFACE BRIDGE PRIORITY PATH-COST HORIZON
0 I ether2 lac_bridge0 0x80 10 none
1 D (unknown) lac_bridge0 0x80 10 none
And on the LNS:
/interface l2tp-server print
Flags: X - disabled, D - dynamic, R - running
# NAME USER MTU CLIENT-ADDRESS UPTIME ENCODING
0 R l2tp-in1 lac_user1 1460 192.168.0.211 5m12s
/interface bridge port print
Flags: X - disabled, I - inactive, D - dynamic
# INTERFACE BRIDGE PRIORITY PATH-COST HORIZON
0 ether2 lns_bridge0 0x80 10 none
1 D (unknown) lns_bridge0 0x80 10 none
Looks like half way done for the first step. Just wondering about the “(unknown)” ports on the Ethernet bridges… somebody has an explanation?
Anyway, now I’ll configure a PPPoE server listening on the bridge interface (lns_bridge0) with a sample user on the LNS:
/ip pool add name=pppoe ranges=10.0.0.10-10.0.0.20
/ppp profile set default local-address=10.0.0.1 remote-address=pppoe
/ppp secret add name=customer1 password=customer1 service=pppoe
/interface pppoe-server server add interface=lns_bridge0 default-profile=default disabled=no
Now the PPPoE server is up and running… Connecting a Windows XP laptop to the ether2 interface of the LNS and trying to connect with the built-in PPPoE client succeeds:
/interface pppoe-server print
Flags: X - disabled, D - dynamic, R - running
# NAME USER SERVICE REMOTE-ADDRESS ENCODING UPTIME
0 DR <pp... cus... 00:C0:9F:96:3... 5s
But if I connect the same laptop on the ether2 interface of the LAC, which should tunnel the PPPoE stuff over the L2TP tunnel to the LAC which in turn should finally terminate the PPPoE sessions, fails.
Am I missing something? I think this setup should work like this, shouldn’t it?
Help to get this ready would really be appreciated!
Bye, Robert.