Taking into account #4552 it is especially important to rewrite the example of granting a privilege to call failover.execute to lua_call, because this way it is possible to switch from tarantool 2.x directly to tarantool 3.x with the failover coordinator (the non-upgraded schema doesn't prevent us from giving the privilege and so the coordinator is able to assign a leader).

The example now is the following:

credentials:
  users:
    replicator:
      password: 'topsecret'
      roles: [ replication ]
      privileges:
      - permissions: [ execute ]
        functions: [ 'failover.execute' ]

Plus a role with box.schema.func.create('failover.execute', {<...>}).

Now, the configuration is the following:

credentials:
  users:
    replicator:
      password: 'topsecret'
      roles: [ replication ]
      privileges:
      - permissions: [ execute ]
        lua_call: [ 'failover.execute' ] # !! changed

And the role is not needed.

It works on 3.2+.

Is works if all the instance are RO on 3.3+ that allows a seamless upgrade from 2.x on 3.3+.