Greetings, On Mon, Mar 11, 2024 at 13:33 normandavis1990 <normandavis1...@proton.me> wrote:
> > On Monday, March 11th, 2024 at 3:43 PM, Stephen Frost < > sfr...@snowman.net> wrote: > > > Greetings, > > > > * normandavis1990 (normandavis1...@proton.me) wrote: > > > > > I have a master and tow standby servers. I want to create another > one. These servers are made by someone else and I am a newbie in PostgreSQL. > > > I found the following two tutorials: > > > > > > [...] > > > > > A) Which on is better and easier? > > > > > > One referred to 9.2, which is extremly old and no longer supported, and > > the other said it was archived ... so I'm not sure either is really > > great to be used today. > > > > > B) In these articles, to create a Standby server, a user is created in > the database. Because there are already two Standby servers, this user is > probably created. How can I find it? Can I use that user to build a third > server? > > > > > > If those systems are connected to the primary, you can query the view > > pg_stat_replication and see what user they are connected with: > > > > SELECT * FROM pg_stat_replication; > > > > You should be able to use the existing user to create a new standby. > > I'd recommend using pg_basebackup to create it with a command along > > these lines: > > > > pg_basebackup -h existing.server.com -U username -D > /destination/directory -c fast -C -S standbyslotname -R -P -v > > > > Running pg_basebackup this way will: > > - Have pg_basebackup connect to 'existing.server.com' (should be your > > primary) > > - Connect as user 'username' (pull this from the 'usename' field in > > pg_stat_replication) > > - Store the data files for the new system into /destination/directory on > > the system where pg_basebackup is run > > - Start the backup immediately by doing a 'fast' checkpoint > > - Create a replication slot to use to make sure the WAL is kept on the > > primary until the new standby system collects it (you should monitor > > this though- if you destroy this new system, WAL could build up on the > > primary). > > - Use 'standbyslotname' as the name of the slot that's created > > - Instructs pg_basebackup to write out the connection information to > > connect to the primary and start streaming when it starts up. > > - Enabled progress reporting from pg_basebackup > > - Enables verbose mode of pg_basebackup > > > > Full documentation of pg_basebackup is here: > > > > https://www.postgresql.org/docs/current/app-pgbasebackup.html > > > > Thanks! > > > > Stephen > > Hi, > Thank you. > Shoudd I run the following command on the mater? > > $ pg_basebackup -h "Master_IP_Address" -U username -D > /destination/directory -c fast -C -S standbyslotname -R -P -v No, on the system you wish to bring up as another standby. Thanks, Stephen >
