Re: [HACKERS] [PostgreSQL 10] default of hot_standby should be "on"?

Magnus Hagander <magnus@hagander.net> writes:
> +1. I definitely think we should do it, and 10 would be the time to do it.

Agreed.  It's mainly a historical accident that the default is what it is,
I think.

> I wonder if we should also consider changing the standby error message to
> be a WARNING instead of an ERROR. So that if you try to start up a standby
> with hot_standby=on but master with wal_level=replica it would turn into a
> cold standby.

I'm -1 for that: if you fat-finger the configuration, you should be told
about it, not have the system start up in an unintended mode that lacks
critical functionality.
        regards, tom lane