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QIDAR588 - serbancalin - 08-15-2025
Hello,
I think this matter would be solved with GRE between S0/0 and S0/0.
Virtual link, in this case do not respect the core purpose.(Create virtual link between back bone area and a area which is not direct connected to backbone)
Thanks!
RE: QIDAR588 - help_desk - 08-16-2025
When the DCI (Area-0) link fails, the OSPF backbone becomes partitioned. OSPF requires a contiguous Area-0. An OSPF virtual link through the common non-backbone Area-110 stitches the two Area-0 halves back together without ISP changes
A GRE tunnel between S0/0–S0/0 could also carry Area-0, but it’s a workaround. You must build and maintain a tunnel, handle MTU, overhead, and run OSPF over it. The virtual link needs no new interfaces and uses the existing OSPF adjacency in Area-110.