Open access from clearly-defined host (staging) to replica db (read-only)

Most probably, one firewall rule needs to be opened to allow this.

12:44 <+olasd> I think it makes sense to open read only access (so, punch a hole in the firewall, and update pg_hba.conf to allow staging hosts to connect as the guest user)

Plan, something along the line of:

• fw: Open rule to allow access
• postgres instance: Allow staging host the connection (pg_hba.conf)
• Update clearly-defined node to integrate the new db access

---

Migrated from T2932 (view on Phabricator)