How to prevent loops in the OSPF backbone 0 area?
Routers in an OSPF autonomous system do not directly transmit routing information to maintain the routing table. They exchange link state information (LSA), and each router maintains a unified link state database.
Each router uses itself as the root node based on the LSDB information and calculates the link cost (cost) to obtain its own routing table.
Because the LSDB is consistent, no routing loop occurs.
Solution 1:
The loop does not need to be explained. Three connected equal areas or devices, A sends to B, B sends to C, and C sends a loop to A.
There are many ways to solve a loop, the most typical of which is this primary method.
STP also uses this method to maintain order and avoid loops.
The OSPF area is maintained by the AREA0.
Solution 2:
Do you think that all networks are connected to the backbone network and are forwarded by the backbone network? Can a loop be formed? The answer is not, but if the backbone network is not connected to the backbone network, a loop may occur.
Solution 3:
OSPF uses the SPF algorithm. The principle is that data can be forwarded to the destination only through the backbone area.