Re: streaming replication question

You can combine warm standby and streaming, we do this in our product
database.
When the standby is to far from the master, the slave will try to use
restore_command to restore the database(warm standby), when the standby
catch up the master, the steaming will working again.

BTW: we use ominipitr.

On Fri, Mar 22, 2013 at 2:32 AM, Roberto Scattini <
roberto(dot)scattini(at)gmail(dot)com> wrote:

> hi list,
>
> i'm installing a streaming replication master-slave setup in ubuntu 12.04
> LTS, with postgresql 9.1
>
> the tutorials and the documentation are a very good start point, but i
> have one question related to some fine grained configurations.
>
> it is said that i should stop the master db in order to make de starting
> backup, OR run pg_start_backup and keep the archive files for the slave to
> catch up. if i dont do this, maybe the slave stays far behind the master
> and the wal_segments arent enough to start the replication.
> if I understand this right, i can "combine" the old "warm standby" configs
> of archive_command in the master and restore command in the slave to ensure
> that the slave will have the necessary info to start the replication.
>
>
> i mean, i can have both configurations enabled?
> right now, my streaming replication setup has this configs:
>
> recovery.conf (slave)
> -----------------------------------
> standby_mode = 'on'
> primary_conninfo = 'host=192.168.206.134'
> trigger_file = '/var/lib/postgresql/9.1/sgi/sgi.trigger'
> restore_command = '/usr/lib/postgresql/9.1/bin/pg_standby -d -k 100 -s 20
> -t /var/lib/postgresql/9.1/sgi.trigger /var/lib/postgresql/9.1/archive %f
> %p'
> archive_cleanup_command = '/usr/lib/postgresql/9.1/bin/pg_archivecleanup
> /var/lib/postgresql/9.1/archive %r'
> -----------------------------------
>
> postgresql.conf (master)
> -----------------------------------
> data_directory = '/var/lib/postgresql/9.1/sgi'
> hba_file = '/etc/postgresql/9.1/sgi/pg_hba.conf'
> ident_file = '/etc/postgresql/9.1/sgi/pg_ident.conf'
> external_pid_file = '/var/run/postgresql/9.1-sgi.pid'
> listen_addresses = '*'
> port = 5432
> max_connections = 100
> unix_socket_directory = '/var/run/postgresql'
> ssl = true
> shared_buffers = 24MB
> wal_level = hot_standby
> archive_mode = on
> archive_command = 'rsync -arv %p 192.168.206.133:/var/lib/postgresql/9.1/archive/%f
> </dev/null'
> archive_timeout = 900
> max_wal_senders = 5
> wal_keep_segments = 100
> log_line_prefix = '%t '
> datestyle = 'iso, mdy'
> lc_messages = 'en_US.UTF-8'
> lc_monetary = 'en_US.UTF-8'
> lc_numeric = 'en_US.UTF-8'
> lc_time = 'en_US.UTF-8'
> default_text_search_config = 'pg_catalog.english'
> -----------------------------------
>
> thanks,
>
> --
> Roberto Scattini
>