Default route to external (or internet) not exist in OSPF routing
Hello all,
In my lab test, I discovered that the default route to the external network (or, in my case, to the Internet) does not exist in OSPF routing in TP-Link ER8411. I'm configuring a Cisco router, a Mikrotik router, and a TP-Link ER8411 (as a main gateway router) using OSPF. Although TP-Link ER8411 has 'basic' OSPF routing, it works fine with other third-party routers except for the default route to the internet (or external network). The route appeared in the routing table of the TP-Link ER8411 but not in the OSPF routing table. The default route does not exist in Mikrotik and Cisco's OSPF routing tables, which (by right) it should have since all three routers shares similar routing entries via OSPF protocol. There is no option to 'inject' the static default route into OSPF routing; I think it should have it. This route injection in a dynamic routing protocol such as OSPF is known as 'redistribute routing information'. This means that any external routing (static or dynamic) is 'injected' into the dynamic routing protocol (OSPF), making the external routes available to the rest of the routers. I think this feature should be available.
The only workaround for this is to set a default static route (0.0.0.0 0.0.0.0 gateway) from the adjacent router (in my lab test, Cisco and Mikrotik) to TP-Link ER8411 (the main gateway router).
Thanks.
Hello @Clive_A
Here is my network diagram based on my lab test on OSPF routing. It would be best if you zoomed in to see the details. As I mentioned earlier, OSPF works in this scenario, but the default route on the TP-Link ER8411 does not 'inject' or 'share' the default route into the OSPF routing domain, although the default route (in Routing Table) exists. The TP-Link MR200 has access to the Internet. The routing configuration on all devices is purely OSPF with no static routes. From the PC part, the traceroute is reachable till 192.168.168.1 (the MR200) but not beyond.
Unless I declare a static route from Mikrotik and Cisco router towards TP-Link ER8411. It is unable to reach the internet space.
Kindly advise.
Thank you very much