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Why are my ECMP routes not working?

Why are my ECMP routes not working?

ECMP routes may not work when advertised to your direct link or transit gateway.

Two ECMP routes in different zones that are advertised to your direct link or transit gateway are not working as ECMP routes.

It is not possible to have two ECMP routes in different zones.

Create the two ECMP routes in the same zone.