Using caddy proxy to access another caddy proxy

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3

Thanks for making this post because I was searching for the answers and beyond. I did find this post too: Running a Caddy server behind another [SOLVED]

I would like to know on which instance (front or back) I should put all the directives in? Does it matter at all?

front instance facing public internet

subdomain.domain.tld {

    reverse_proxy http://192.168.1.50

    basic_auth {

        <username> <hash>

    }

}

back instance 192.168.1.50 facing private subnet

http://subdomain.domain.tld {

    reverse_proxy <docker-container>:<port>

}