[ADMIN] Shutdown Order with Primary/Standby?

Just wondering if there's a best practice in regards to shutdown of primary and standbys, as I approach my first planned maintenance task as a newbie PostgreSQL DBA. I found one older post that suggested doing a fast-mode shutdown on primary first so that all transaction info can be cleanly pushed to standby, then shutdown the standby. Our big app group runs on 9.2.18 and is being upgraded to 9.2.22.

Extending that scenario, if you had a cascading standby, would you go primary -> upstream standby -> downstream standby?

Curious what folks think.

Don.
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