setup replica master slave in AWS Linux 2

Is there a document on how to set up a replication master-slave in AWS Linux 2?  Is it the same as in Linux Redhat?

When I install and initdb in AWS Linux 2, it's already created postgres os user.  I can't establish from one server to another.  There's a ECDSA to the list of known host.  Permission denied (publickey, gssapi-keyex, gssapi-with-mic)

Bach-Nga

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