The confusion of configuring cluster.initial_master_nodes

[yc1024]

Unfortunately，i haven't modified it since I configured cluster.initial_master_nodes and discovery.seed_hosts, and this is the first time I started the newly installed cluster.
This is the second time I have encountered this problem.

I once asked such a question：

Why node uuid replace by {bootstrap-placeholder}-{NodeName}

At the time the cluster bootstrapped, it did not know the ID of master 3 so it uses a placeholder that will be replaced with master 3's ID later. This is quite a low-level implementation detail that almost certainly isn't relevant to your problem You did not set cluster.initial_master_nodes to the same value on all three nodes, or you have changed it after the first time you started these nodes. Not obviously, but if you changed cluster.initial_master_nodes then that was wrong.