OSPF default route

RouterOS Forwarding Protocols
1

Hey everyone,

I’m trying to setup an one are OSPF configuration with 3 routers and a backup Internet access.
1 router (HOP) have no Internet access without the OSPF (working)
1 router (CMC) have an Internet access without the OSPF (working)
1 router (PTR) have an Internet access and a 4G backup Internet access (working)
If the Internet access of one router break the other is working as a intermediary. (working)

I would like the 4G backup access to activate if the twos links break.

What’s happening:
If the link on PTR breaks the router is reaching Internet via the backup link and not using the link from CMC.
I’ve tried to play with the cost, but if the cost of my backup is higher than the OSPF one’s, the router is trying to reach Internet via the OSPF links, which is good if the link on CMC is okay, but not working if the link is down…

If you have any idea or any questions, don’t hesitate!

Best regards

2

Checkout “originate-default” in “help.mikrotik.com/docs/display/ROS/OSPF”. It can also be combined with routing filters.

3

Hey @Larsa

I agree with the idea, but if I configure, for example on PTR, my ospf port to never originate-default, if the Internet link break the local LAN will access Internet via the 4G backup link and not the CMC link or they will have no Internet access if the Internet link and the 4G backup link break.
A solution would be to connect my backup port on a intermediate router which would have Internet access. Then configure OSPF on the backup port with a higher cost. But I don’t like this solution.

Regards

4

Now I get it. I completely missed the part that CMC wasn’t configured with OSPF.