Обсуждение: [GENERAL] hot standby questions
Hi Just trying to put together the hot_standby setup All docs I read are pointing to use as prefered method to use pg_basebackup to set the base So far so good But psql postgres -c "select pg_start_backup('backup')" pg_basebackup -D /var/lib/pgsql/sample -Ft -z -P psql postgres -c "select pg_stop_backup()" will get me on target < 2017-08-02 22:09:45.348 CDT >LOG: database system was interrupted; last known up at 2017-08-02 22:06:28 CDT < 2017-08-02 22:09:45.353 CDT >LOG: entering standby mode < 2017-08-02 22:09:45.353 CDT >LOG: invalid primary checkpoint record < 2017-08-02 22:09:45.353 CDT >LOG: invalid secondary checkpoint record < 2017-08-02 22:09:45.353 CDT >PANIC: could not locate a valid checkpoint record < 2017-08-02 22:09:45.523 CDT >LOG: startup process (PID 10895) was terminated by signal 6: Aborted < 2017-08-02 22:09:45.523 CDT >LOG: aborting startup due to startup process failure where as psql postgres -c "select pg_start_backup('backup')" pg_basebackup -D /var/lib/pgsql/sample -Ft -z -P -x psql postgres -c "select pg_stop_backup()" I am good to go Pretty much every where I looked at -x is not mentioned to be used So what gives ? What did I miss ? It's gotta be soomething Thanks Armand
On Wed, Aug 2, 2017 at 8:19 PM, armand pirvu <armand.pirvu@gmail.com> wrote:
Hi
Just trying to put together the hot_standby setup
All docs I read are pointing to use as prefered method to use pg_basebackup to set the base
So far so good
But
psql postgres -c "select pg_start_backup('backup')"
pg_basebackup -D /var/lib/pgsql/sample -Ft -z -P
psql postgres -c "select pg_stop_backup()"
pg_basebackup does the equivalent of pg_start_backup and pg_stop_backup for you. It is not helpful, and might even sometimes be harmful, to do them yourself when using pg_basebackup.
Pretty much every where I looked at -x is not mentioned to be used
So what gives ? What did I miss ? It's gotta be soomething
That certainly isn't my experience. If you find sites that don't mention -x, -X, or --xlog-method, then I would be reluctant to take any of that site's other advice seriously.
But note that in version 10, -x will go away and the default will be changed so that not specifying anything will be the same as -X stream. perhaps you are reading advice aimed at a future version.
Cheers,
Jeff
2017-08-04 5:58 GMT+12:00 Jeff Janes <jeff.janes@gmail.com>:
On Wed, Aug 2, 2017 at 8:19 PM, armand pirvu <armand.pirvu@gmail.com> wrote:
Hi
Just trying to put together the hot_standby setup
All docs I read are pointing to use as prefered method to use pg_basebackup to set the base
So far so good
But
psql postgres -c "select pg_start_backup('backup')"
pg_basebackup -D /var/lib/pgsql/sample -Ft -z -P
psql postgres -c "select pg_stop_backup()"pg_basebackup does the equivalent of pg_start_backup and pg_stop_backup for you. It is not helpful, and might even sometimes be harmful, to do them yourself when using pg_basebackup.
Pretty much every where I looked at -x is not mentioned to be used
So what gives ? What did I miss ? It's gotta be soomethingThat certainly isn't my experience. If you find sites that don't mention -x, -X, or --xlog-method, then I would be reluctant to take any of that site's other advice seriously.But note that in version 10, -x will go away and the default will be changed so that not specifying anything will be the same as -X stream. perhaps you are reading advice aimed at a future version.Cheers,Jeff
I use pg_basebackup every day and the way I do is:
pg_basebackup -D /destination --checkpoint=fast --xlog-method=stream
The --xlog-method=stream option will copy the wal_files as well (to pg_xlogs directory).
That works pretty well for me. You can either add the compress option too. Hope this was helpful.
Cheers,
Lucas
Thank you guys
I think I kinda shot myself in the foot. I took a look at the wiki and I put in -x and so far so good
— Armand
On Aug 3, 2017, at 11:03 PM, Lucas Possamai <drum.lucas@gmail.com> wrote:2017-08-04 5:58 GMT+12:00 Jeff Janes <jeff.janes@gmail.com>:On Wed, Aug 2, 2017 at 8:19 PM, armand pirvu <armand.pirvu@gmail.com> wrote:
Hi
Just trying to put together the hot_standby setup
All docs I read are pointing to use as prefered method to use pg_basebackup to set the base
So far so good
But
psql postgres -c "select pg_start_backup('backup')"
pg_basebackup -D /var/lib/pgsql/sample -Ft -z -P
psql postgres -c "select pg_stop_backup()"pg_basebackup does the equivalent of pg_start_backup and pg_stop_backup for you. It is not helpful, and might even sometimes be harmful, to do them yourself when using pg_basebackup.
Pretty much every where I looked at -x is not mentioned to be used
So what gives ? What did I miss ? It's gotta be soomethingThat certainly isn't my experience. If you find sites that don't mention -x, -X, or --xlog-method, then I would be reluctant to take any of that site's other advice seriously.But note that in version 10, -x will go away and the default will be changed so that not specifying anything will be the same as -X stream. perhaps you are reading advice aimed at a future version.Cheers,JeffI use pg_basebackup every day and the way I do is:pg_basebackup -D /destination --checkpoint=fast --xlog-method=streamThe --xlog-method=stream option will copy the wal_files as well (to pg_xlogs directory).That works pretty well for me. You can either add the compress option too. Hope this was helpful.Cheers,Lucas