Community discussions

 
ibm
Member
Member
Topic Author
Posts: 301
Joined: Mon May 12, 2014 5:16 pm

OSPF and choice of addressing

Thu Feb 12, 2015 12:20 pm

Hi, I'm planning a routed OSPF network with the following addressing and I would know if it's a good choice to put also the BTS router with the AP attached in OSPF routing and also if the addresses are correctly choosen.
The L indicates the Loopback.
I would also access to the bridged router that have the radio for PTP but I don't want to add them in OSPF area, how I can reach them?
Image
 
ibm
Member
Member
Topic Author
Posts: 301
Joined: Mon May 12, 2014 5:16 pm

Re: OSPF and choice of addressing

Fri Feb 13, 2015 11:05 am

I tested redistribute connected and redistribute static and it worked, but now I don't know why if I redistribute also default route the router from the first to last hop can't reach the internet.
 
ibm
Member
Member
Topic Author
Posts: 301
Joined: Mon May 12, 2014 5:16 pm

Re: OSPF and choice of addressing

Thu Feb 26, 2015 2:10 pm

Anyone?
 
User avatar
ScottReed
Member Candidate
Member Candidate
Posts: 111
Joined: Thu Sep 24, 2009 9:47 pm
Location: Montana / Western Massachusetts

Re: OSPF and choice of addressing

Thu Feb 26, 2015 3:55 pm

Hey @ibm -

Sorry if I'm missing something here but which router is your core where your internet connection ties into your network?

I'm assuming you're running a single OSPF instance all in the backbone area?

The router which maintains the default route to the internet should be the only router and only OSPF instance set to "Distribute Default Route" in your backbone area. This core router should also only specify the /32 loopback(s) and /30 link network(s) in /routing ospf network

The other routers should be specifying the /32 loopback network and /30 link network(s) in /routing ospf network. These routers should (could) be set to "Redistribute Connected".

Again, I am making some assumptions so the above might be wrong. But, I hope it gives you some pointers. Let me know.

And to end, I would recommend you add a link in your network to close off a loop and create redundancy. Say BTSB to BTSC ??
 
ibm
Member
Member
Topic Author
Posts: 301
Joined: Mon May 12, 2014 5:16 pm

Re: OSPF and choice of addressing

Thu Feb 26, 2015 5:47 pm

Hey @ibm -

Sorry if I'm missing something here but which router is your core where your internet connection ties into your network?

I'm assuming you're running a single OSPF instance all in the backbone area?

The router which maintains the default route to the internet should be the only router and only OSPF instance set to "Distribute Default Route" in your backbone area. This core router should also only specify the /32 loopback(s) and /30 link network(s) in /routing ospf network

The other routers should be specifying the /32 loopback network and /30 link network(s) in /routing ospf network. These routers should (could) be set to "Redistribute Connected".

Again, I am making some assumptions so the above might be wrong. But, I hope it gives you some pointers. Let me know.

And to end, I would recommend you add a link in your network to close off a loop and create redundancy. Say BTSB to BTSC ??
Thanks a lot for the answer.
The router that have internet connectivity is the PPPoE server, so only it have redistribute-default enabled.
Actually the connectivity isn't really necessary on the core routers because on the endpoint routers there is a eoip tunnel that allows pppoe to server.
For the loop to redound the network is there any precaution to be taken (I mean the cost and priority settings)?
I post you the export, can you give a check also to the MTU?

This is the PPPoE server test configuration:
/interface bridge
add mtu=1554 name=bridge_pppoe
add mtu=1554 name=bridge_wan
add mtu=1500 name=lo
/interface wireless
set [ find default-name=wlan1 ] band=2ghz-b/g/n disabled=no frequency=2422 l2mtu=2290 mode=station-bridge ssid="test" tx-power=14 tx-power-mode=all-rates-fixed
/interface ethernet
set [ find default-name=ether2 ] mtu=1554
/interface eoip
add !keepalive mac-address=XX:XX:XX:XX:71:7E mtu=1512 name=eoip-tunnel1 remote-address=10.1.0.6 tunnel-id=0
/ppp profile
set 0 dns-server=10.1.0.1 local-address=10.128.0.1 use-compression=no use-mpls=no use-vj-compression=no
set 1 dns-server=10.1.0.1 local-address=10.128.0.1 use-compression=no use-mpls=no use-vj-compression=no
/routing ospf instance
set [ find default=yes ] redistribute-static=as-type-1 router-id=10.101.0.1
/interface bridge port
add bridge=bridge_wan interface=wlan1
add bridge=bridge_wan interface=ether1
add bridge=bridge_pppoe interface=eoip-tunnel1
/interface pppoe-server server
add authentication=chap,mschap2 disabled=no interface=bridge_pppoe max-mru=1500 max-mtu=1500 service-name=service1
/ip address
add address=10.1.0.1/30 interface=ether2 network=10.1.0.0
add address=10.101.0.1/32 interface=lo network=10.101.0.1
/ip dhcp-client
add dhcp-options=hostname,clientid interface=bridge_wan
add default-route-distance=0 dhcp-options=hostname,clientid disabled=no interface=wlan1
/ip firewall nat
add action=masquerade chain=srcnat out-interface=bridge_wan
/ip route
add disabled=yes distance=1 dst-address=192.168.0.190/32 gateway=bridge_wan
/ppp secret
add name=test password=test profile=default-encryption remote-address=10.1.0.200 service=pppoe
/routing ospf interface
add authentication=md5 authentication-key=test interface=ether2 network-type=broadcast
/routing ospf network
add area=backbone network=10.1.0.0/30
add area=backbone network=10.1.0.4/30
This is the AP1:
/interface bridge
add mtu=1554 name=bridge1
add mtu=1500 name=lo
/interface wireless
set [ find default-name=wlan1 ] l2mtu=2290
/interface ethernet
set [ find default-name=ether2 ] mtu=1554
/interface eoip
add !keepalive mac-address=XX:XX:XX:XX:XX:9B mtu=1512 name=eoip1 \
    remote-address=10.1.0.1 tunnel-id=0
/interface pppoe-client
add disabled=no interface=bridge1 max-mru=1500 max-mtu=1500 mrru=1600 name=\
    pppoe-out1 password=test profile=default-encryption user=test
/routing ospf instance
set [ find default=yes ] redistribute-connected=as-type-1 \
    redistribute-static=as-type-1 router-id=10.101.0.6
/interface bridge port
add bridge=bridge1 interface=eoip1
/ip address
add address=10.1.0.6/30 interface=ether2 network=10.1.0.4
add address=10.101.0.6/32 interface=lo network=10.101.0.6
/ip route
add distance=1 gateway=pppoe-out1
/routing ospf interface
add authentication=md5 authentication-key=test interface=ether2 network-type=\
    broadcast
/routing ospf network
add area=backbone network=10.1.0.4/30
 
User avatar
ScottReed
Member Candidate
Member Candidate
Posts: 111
Joined: Thu Sep 24, 2009 9:47 pm
Location: Montana / Western Massachusetts

Re: OSPF and choice of addressing

Thu Feb 26, 2015 6:03 pm

The IP addresses in your config don't match up to the IP's on your diagram for PPPoE Server and AP1. Also, you show no config for Router BTSC. Also, you specify a loopback (lo) but you never add its subnet to /routing ospf network. You should, as it will tie the lo interface to the default instance and prevent the instance from going down in the case of a link failure.

If you are doing EoIP you need to form EoIP from PPPoE Server to Router BTSC and then to AP1.

Also, bear in mind that because EoIP is bridging a flat layer2 network, you cannot introduce loops in it.

I use MTU 1530 on any EoIP tunnels that I create in my network. However, I do not know about or use PPPoE but I do know there are some MTU regulations on that.

In regards to forming redundancy from BTSB to BTSC, you shouldn't need to change the path cost on the OSPF Interfaces. The default is 10 and the costs should calculate accordingly. However, if you wish to force traffic to flow a certain direction than you do need to modify path cost.

As for priority, the router with the higher priority (higher number) will take precedence in being the DR (designated router).

I will pull some config snippets from my network where I have EoIP running 3 hops out from my core router. Don't have time to do it right now.
 
ibm
Member
Member
Topic Author
Posts: 301
Joined: Mon May 12, 2014 5:16 pm

Re: OSPF and choice of addressing

Thu Feb 26, 2015 6:13 pm

Sorry I forgot to say that I refer to AP1 connected to router BTSA (the upper in diagram).
Why have I set EoIP tunnel on BTS Routers? I need PPPoE client only on AP.

Who is online

Users browsing this forum: No registered users and 19 guests