OSPF routing links and notes
- This is not a explanation of ospf, just interesting notes.
sham-links -> ospf + mpls-mp-bgp
- The problem
- When using a providers mpls network to connect site, ospf is redistributed into bgp and back out to ospf at the other sites.
- The problem is that the routes are redistributed back to ospf as inter-area(From another area)
- this causes ospf to ignore the route, if there is any other intra-area(Same area) links available.
- Solution
- sham-links changes the behavior on PE routers
- Config of sham links
- Each PE needs loopback in same vrf as sham endpoints, e.g. 99.99.99.1, should be able to ping loopbacks in vrf from PE to PE
- Under PE ospf add sham link
SPEDGE1(config)#router ospf 2 vrf CUSTOMER SPEDGE1(config-router)#area 0 sham-link 99.99.99.1 99.99.99.2 !
- The problem
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