Why the ASBR does not generate equal-cost route

Two areas are configured on two devices separately, for example:

SwitchA:
area 0: 10.5.5.5
area 1: 10.4.4.4
SwitchB:
area 0: 10.5.5.6
area 1: 10.4.4.6
Adjacencies are formed on the devices separately.

Thus, the next-hop of a route that SwitchB learns from SwitchA should be 10.5.5.5 or 10.4.4.4. However, the route on SwitchB goes through only 10.4.4.4 in area 1 as the gateway and no load sharing can be performed.

This is because when multiple equal-cost routes exist, an ASBR selects the route with the greatest area ID.

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