# Adjacency Required for Learning Routes?

**URL:** https://forum.networklessons.com/t/adjacency-required-for-learning-routes/51515
**Category:** OSPF
**Created:** [August 22, 2024, 2:42am UTC](https://forum.networklessons.com/t/adjacency-required-for-learning-routes/51515 "2024-08-22T02:42:44Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![bkcashman](https://cdn-forum.networklessons.com/letter_avatar_proxy/v4/letter/b/85e7bf/32.png) [@bkcashman](https://forum.networklessons.com/u/bkcashman)
#### Post date: [August 22, 2024, 2:42am UTC](https://forum.networklessons.com/t/adjacency-required-for-learning-routes/51515/1 "2024-08-22T02:42:44Z")

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Hi,  
Hoping you can help understand what is happening in the following case. I have 4 Juniper routers connected in a ring by GRE tunnels. So router A ↔ B ↔ C ↔ D ↔ A. I’m using OSPF with interface type point to point. I am exporting the loopback addr of each router into OSPF with an export policy. What I was trying to do is have each router have 2 ways to get to any other router (clockwise or counterclockwise around the ring). What actually happens is that Router A has 2 routes to Router C, but only one route to Router B and to Router D. Router A to C makes sense because Router A has adjacency with Router B and Router D via point to point, and C has adjacency with B (learns one route to A), and D also has adjacency with C (so C learns a second route to A). If C knows 2 routes back to A, why doesn’t that information propagate to B? All the routers are in the same area. I think I need to fully mesh so that all the routers are adjacent to each other, but why doesn’t OSPF just handle this case?  
Thanks!  
Bill C