OSPF between FGT and Meraki MX - how? why no neighbor?

[scheuri]

Hi all

I am supposed to configure OSPF peering between a Fortigate and a Meraki Hub (MX?).

Unfortunately there is not much to configure on Meraki side (it has the correct ospf ID and an unique router ID and identical Hello and Dead timeouts). So I suppose I need to do that on my site on the FGT.

Has someone an idea why the meraki does not show up on my neighbor list?

Information I have:

• I made a new OSPF subarea ID (1.1.1.17) which is configured on Fortigate and MX
• They are connected to the same LAN 10.x.x.x/23 and FGT can ping the MX (and vice versa)
• Both devices send out proto 89 packets to 224.0.0.5
• The LAN segment is on port1 of the Fortigate
• I added that port1 as OSPF interface (which I guess is correct)
• The OSPF interface is on network-type broadcast at the moment
• The OSPF interface (port1) is coming up as in area 0.0.0.0 instead of 1.1.1.17 according to "get router info ospf interface port1" (see [2])
• The reason might be, as the network 10.x.x.x/23 is already configured in "config router ospf - config network" and is in area 0.0.0.0 (because I want this network range to be advertise into area 0.0.0.0).
• I guess the above point is bad, right? Because I want another neighbor for area 1.1.1.17 in this network area which already is in 0.0.0.0

How would I advertise 10.x.x.x/23 into all other OSPF areas while still be able to put in 1.1.1.17 in order to do some broadcast OSPF neigbhouring?

[2]

port1 is up, line protocol is up

Internet Address 10.21.204.1/23, Area 0.0.0.0, MTU 1500

Process ID 0, VRF 0, Router ID 10.21.204.1, Network Type POINTOPOINT, Cost: 1

Transmit Delay is 1 sec, State Point-To-Point

Timer intervals configured, Hello 10.000, Dead 40, Wait 40, Retransmit 5

Hello due in 00:00:02

Neighbor Count is 0, Adjacent neighbor count is 0

Crypt Sequence Number is 21

Hello received 0 sent 1055356, DD received 0 sent 0

LS-Req received 0 sent 0, LS-Upd received 0 sent 0

LS-Ack received 0 sent 0, Discarded 0

Thanks a lot for your help

[srajeswaran · Accepted solution]

Your understanding is correct, you cannot put 10.x.x.x/23 under 2 different areas, but you don't have to worry about this subnet getting advertised to different areas. By default OSPF will database will get this information as a summary route.

in otherwords, if you put 10.x.x.x/23 in 1.1.1.17 , area 0 will be aware about this as a summary route and other OSPF neighbors connected to area 0 will also get the same.

[scheuri]

Thank you very much for your reply - that worked without issues.

I changed the network 10.x.x.x/23 to the new (sub)area and it was a) still advertised via 0.0.0.0 and b) the neighbor peering with Meraki came up as "full"!

Thank you again!