Thanks! On Fri, Dec 15, 2017 at 1:56 PM, Stefano <stefanocire...@gmail.com> wrote:
> For n.2, you can promote the standby to became a standalone (r/w) server. > This may be done via "pg_ctl -D $PGDATA promote" or, if in the > recovery.conf a "triggerfile" definition has been set, touch-ing the > triggerfile. > see https://www.postgresql.org/docs/current/static/standby-settings.html > https://www.postgresql.org/docs/10/static/app-pg-ctl.html > > regards > > 2017-12-15 19:30 GMT+01:00 Tiffany Thang <tiffanyth...@gmail.com>: > >> Thanks Magnus. I did not realize I could use the Hot Standby in read-only >> mode. >> >> For #2, would it be possible to open the Hot Standby in read/write after >> breaking the replication and taking a snapshot or can Hot Standby only be >> open in read/write after a failover? I hoping I can use the same Hot >> Standby for both #1 and #2. >> >> Thanks again. >> >> >> On Fri, Dec 15, 2017 at 12:55 PM, Magnus Hagander <mag...@hagander.net> >> wrote: >> >>> On Fri, Dec 15, 2017 at 6:03 PM, Tiffany Thang <tiffanyth...@gmail.com> >>> wrote: >>> >>>> Hi, >>>> In PostgreSQL, would it be possible to >>>> >>>> 1. set up a read-only slave database? The closest solution I could find >>>> is Hot Standby but the slave would not be accessible until after a >>>> failover. >>>> >>> >>> Hot Standby will give you a standby database that is accessible, but in >>> read-only mode. This sounds like what you're looking for. >>> >>> >>> >>>> 2. temporary convert a read-only slave in read-write mode for testing >>>> read/write workloads? Currently in Oracle, we can temporary open our >>>> read-only standby database in read-write mode to occasionally test our >>>> read-write workloads. We would stop the log apply on the standby database, >>>> convert the read-only database to read-write, >>>> perform our read/write test, discard all the changes after testing and >>>> reopen and resync the standby database in read-only mode. Is there a >>>> similar feature in PostgreSQL or are there ways to achieve something close >>>> to our needs? >>>> >>> >>> No, you can't do this with postgres natively. >>> >>> You could snapshot your filesystem before opening it and then roll back >>> to that snapshot, or something like that, but you cannot do it with just >>> PostgreSQL functionality. >>> >>> -- >>> Magnus Hagander >>> Me: https://www.hagander.net/ <http://www.hagander.net/> >>> Work: https://www.redpill-linpro.com/ <http://www.redpill-linpro.com/> >>> >> >> > > > -- > /* =================================================== */ > > "Il libero scambio รจ come la libera volpe nel libero pollaio" > > Serge Latouche, Bergamo, Maggio 2015 > /* =================================================== */ >
