管理し、単一障害点やスプリットブレインの起きない堅牢なクラスタを運用することが可能です。
</para>
<para>
- この設定例では<productname>PostgreSQL</productname> 14を使っていますが、
+ この設定例では<productname>PostgreSQL</productname> 15を使っていますが、
各種スクリプトは<productname>PostgreSQL</productname> 10以降での動作確認を行っています。
</para>
<sect2 id="example-cluster-requirement">
<tbody>
<row>
<entry>PostgreSQLバージョン</entry>
- <entry>14.0</entry>
+ <entry>15.0</entry>
<entry>-</entry>
</row>
<row>
</row>
<row>
<entry>$PGDATA</entry>
- <entry>/var/lib/pgsql/14/data</entry>
+ <entry>/var/lib/pgsql/15/data</entry>
<entry>-</entry>
</row>
<row>
<entry>有効</entry>
<entry>-</entry>
</row>
- <row>
- <entry>自動起動</entry>
- <entry>有効</entry>
- <entry>-</entry>
- </row>
</tbody>
</tgroup>
</table>
<entry>有効</entry>
<entry>ハートビート方式</entry>
</row>
- <row>
- <entry>自動起動</entry>
- <entry>有効</entry>
- <entry>-</entry>
- </row>
</tbody>
</tgroup>
</table>
</para>
<programlisting>
[全サーバ]# yum install -y https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm
-[全サーバ]# yum install -y postgresql14-server
+[全サーバ]# yum install -y postgresql15-server
</programlisting>
<para>
exclude=pgpool*
+[pgdg15]
+...
+exclude=pgpool*
+
[pgdg14]
...
exclude=pgpool*
[pgdg10]
...
-exclude=pgpool*
-
-[pgdg96]
-...
exclude=pgpool*
</programlisting>
<productname>Pgpool-II</productname>をインストールします。
</para>
<programlisting>
-[全サーバ]# yum install -y https://www.pgpool.net/yum/rpms/4.3/redhat/rhel-7-x86_64/pgpool-II-release-4.3-1.noarch.rpm
-[全サーバ]# yum install -y pgpool-II-pg14-*
+[全サーバ]# yum install -y https://www.pgpool.net/yum/rpms/4.4/redhat/rhel-7-x86_64/pgpool-II-release-4.4-1.noarch.rpm
+[全サーバ]# yum install -y pgpool-II-pg15-*
</programlisting>
</sect2>
</para>
<programlisting>
[server1]# su - postgres
-[server1]$ /usr/pgsql-14/bin/initdb -D $PGDATA
+[server1]$ /usr/pgsql-15/bin/initdb -D $PGDATA
</programlisting>
<para>
[全サーバ]# firewall-cmd --reload
</programlisting>
</listitem>
-
- <listitem>
- <para>
- <productname>Pgpool-II</productname>の自動起動設定を全てのサーバで行います。
- </para>
- <programlisting>
-[全サーバ]# systemctl enable pgpool.service
- </programlisting>
-
- <note>
- <para>
- <productname>Pgpool-II</productname>を自動起動にした場合、
- サーバ起動後に<productname>PostgreSQL</productname>を起動できるだけの時間を
- <xref linkend="guc-search-primary-node-timeout">に設定してください。
- <literal>search_primary_node_timeout</literal>の間にバックエンドの
- <productname>PostgreSQL</productname>に接続できない場合、
- <productname>Pgpool-II</productname>は<productname>PostgreSQL</productname>に接続できなくなります。
- </para>
- </note>
-
- </listitem>
</itemizedlist>
</sect2>
backend_hostname0 = 'server1'
backend_port0 = 5432
backend_weight0 = 1
-backend_data_directory0 = '/var/lib/pgsql/14/data'
+backend_data_directory0 = '/var/lib/pgsql/15/data'
backend_flag0 = 'ALLOW_TO_FAILOVER'
backend_hostname1 = 'server2'
backend_port1 = 5432
backend_weight1 = 1
-backend_data_directory1 = '/var/lib/pgsql/14/data'
+backend_data_directory1 = '/var/lib/pgsql/15/data'
backend_flag1 = 'ALLOW_TO_FAILOVER'
backend_hostname2 = 'server3'
backend_port2 = 5432
backend_weight2 = 1
-backend_data_directory2 = '/var/lib/pgsql/14/data'
+backend_data_directory2 = '/var/lib/pgsql/15/data'
backend_flag2 = 'ALLOW_TO_FAILOVER'
</programlisting>
<programlisting>
[全サーバ]# vi /etc/pgpool-II/failover.sh
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
[全サーバ]# vi /etc/pgpool-II/follow_primary.sh
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
</programlisting>
<para>
これらのファイルをプライマリサーバ(<literal>server1</literal>)のデータベースクラスタ配下に配置します。
</para>
<programlisting>
-[server1]# cp -p /etc/pgpool-II/sample_scripts/recovery_1st_stage.sample /var/lib/pgsql/14/data/recovery_1st_stage
-[server1]# cp -p /etc/pgpool-II/sample_scripts/pgpool_remote_start.sample /var/lib/pgsql/14/data/pgpool_remote_start
-[server1]# chown postgres:postgres /var/lib/pgsql/14/data/{recovery_1st_stage,pgpool_remote_start}
+[server1]# cp -p /etc/pgpool-II/sample_scripts/recovery_1st_stage.sample /var/lib/pgsql/15/data/recovery_1st_stage
+[server1]# cp -p /etc/pgpool-II/sample_scripts/pgpool_remote_start.sample /var/lib/pgsql/15/data/pgpool_remote_start
+[server1]# chown postgres:postgres /var/lib/pgsql/15/data/{recovery_1st_stage,pgpool_remote_start}
</programlisting>
<para>
基本的には<emphasis>PGHOME</emphasis>を環境に合わせて変更すれば、動作します。
</para>
<programlisting>
-[server1]# vi /var/lib/pgsql/14/data/recovery_1st_stage
+[server1]# vi /var/lib/pgsql/15/data/recovery_1st_stage
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
-[server1]# vi /var/lib/pgsql/14/data/pgpool_remote_start
+[server1]# vi /var/lib/pgsql/15/data/pgpool_remote_start
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
</programlisting>
<programlisting>
wd_lifecheck_method = 'heartbeat'
- # Method of watchdog lifecheck ('heartbeat' or 'query' or 'external')
- # (change requires restart)
wd_interval = 10
- # lifecheck interval (sec) > 0
- # (change requires restart)
</programlisting>
<para>
<xref linkend="guc-wd-lifecheck-method">が<literal>heartbeat</literal>に設定されている場合、
</para>
<programlisting>
heartbeat_hostname0 = 'server1'
- # Host name or IP address used
- # for sending heartbeat signal.
- # (change requires restart)
heartbeat_port0 = 9694
- # Port number used for receiving/sending heartbeat signal
- # Usually this is the same as heartbeat_portX.
- # (change requires restart)
heartbeat_device0 = ''
- # Name of NIC device (such like 'eth0')
- # used for sending/receiving heartbeat
- # signal to/from destination 0.
- # This works only when this is not empty
- # and pgpool has root privilege.
- # (change requires restart)
heartbeat_hostname1 = 'server2'
heartbeat_port1 = 9694
</para>
<programlisting>
wd_heartbeat_keepalive = 2
- # Interval time of sending heartbeat signal (sec)
- # (change requires restart)
wd_heartbeat_deadtime = 30
- # Deadtime interval for heartbeat signal (sec)
- # (change requires restart)
</programlisting>
<para>
<application>Watchdog</application>プロセスが異常終了した場合に、
</para>
<programlisting>
wd_escalation_command = '/etc/pgpool-II/escalation.sh'
- # Executes this command at escalation on new active pgpool.
- # (change requires restart)
</programlisting>
<para>
サンプルスクリプト<ulink url="https://git.postgresql.org/gitweb/?p=pgpool2.git;a=blob_plain;f=src/sample/scripts/escalation.sh.sample;hb=refs/heads/V4_4_STABLE">escalation.sh</ulink>は
</para>
<programlisting>
[server1]# su - postgres
-[server1]$ /usr/pgsql-14/bin/pg_ctl start -D $PGDATA
+[server1]$ /usr/pgsql-15/bin/pg_ctl start -D $PGDATA
</programlisting>
<para>
<literal>server1</literal>、<literal>server2</literal>、<literal>server3</literal>で
フェイルオーバするかどうか確認してみます。
</para>
<programlisting>
-[server1]$ pg_ctl -D /var/lib/pgsql/14/data -m immediate stop
+[server1]$ pg_ctl -D /var/lib/pgsql/15/data -m immediate stop
</programlisting>
<para>
<literal>ノード1</literal>を停止後、フェイルオーバが発生し、<literal>server2</literal>が
servers to create a robust cluster system and avoid the single point of failure or split brain.
</para>
<para>
- <productname>PostgreSQL</productname> 14 is used in this configuration example.
+ <productname>PostgreSQL</productname> 15 is used in this configuration example.
All scripts have been tested with <productname>PostgreSQL</productname> 10 and later.
</para>
<sect2 id="example-cluster-requirement">
<tbody>
<row>
<entry>PostgreSQL Version</entry>
- <entry>14.0</entry>
+ <entry>15.0</entry>
<entry>-</entry>
</row>
<row>
</row>
<row>
<entry>$PGDATA</entry>
- <entry>/var/lib/pgsql/14/data</entry>
+ <entry>/var/lib/pgsql/15/data</entry>
<entry>-</entry>
</row>
<row>
<entry>Enable</entry>
<entry>-</entry>
</row>
- <row>
- <entry>Start automatically</entry>
- <entry>Enable</entry>
- <entry>-</entry>
- </row>
</tbody>
</tgroup>
</table>
<entry>on</entry>
<entry>Life check method: heartbeat</entry>
</row>
- <row>
- <entry>Start automatically</entry>
- <entry>Enable</entry>
- <entry>-</entry>
- </row>
</tbody>
</tgroup>
</table>
</para>
<programlisting>
[all servers]# yum install -y https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm
-[all servers]# yum install -y postgresql14-server
+[all servers]# yum install -y postgresql15-server
</programlisting>
<para>
Since <productname>Pgpool-II</productname> related packages are also included in <productname>PostgreSQL</productname> YUM repository,
...
exclude=pgpool*
+[pgdg15]
+...
+exclude=pgpool*
+
[pgdg14]
...
exclude=pgpool*
[pgdg10]
...
-exclude=pgpool*
-
-[pgdg96]
-...
exclude=pgpool*
</programlisting>
Install <productname>Pgpool-II</productname> from Pgpool-II YUM repository.
</para>
<programlisting>
-[all servers]# yum install -y https://www.pgpool.net/yum/rpms/4.3/redhat/rhel-7-x86_64/pgpool-II-release-4.3-1.noarch.rpm
-[all servers]# yum install -y pgpool-II-pg14-*
+[all servers]# yum install -y https://www.pgpool.net/yum/rpms/4.4/redhat/rhel-7-x86_64/pgpool-II-release-4.4-1.noarch.rpm
+[all servers]# yum install -y pgpool-II-pg15-*
</programlisting>
</sect2>
</para>
<programlisting>
[server1]# su - postgres
-[server1]$ /usr/pgsql-14/bin/initdb -D $PGDATA
+[server1]$ /usr/pgsql-15/bin/initdb -D $PGDATA
</programlisting>
<para>
[all servers]# firewall-cmd --reload
</programlisting>
</listitem>
-
- <listitem>
- <para>
- We set <productname>Pgpool-II</productname> to start automatically on all servers.
- </para>
- <programlisting>
-[all servers]# systemctl enable pgpool.service
- </programlisting>
-
- <note>
- <para>
- If you set the auto-start of <productname>Pgpool-II</productname>, you need to
- change the <xref linkend="guc-search-primary-node-timeout"> to an appropriate
- value that you can start the <productname>PostgreSQL</productname> after the
- server has been started.
- <productname>Pgpool-II</productname> will fail if it can't connect to the
- <productname>PostgreSQL</productname> on the backend during the
- <literal>search_primary_node_timeout</literal>.
- </para>
- </note>
-
- </listitem>
</itemizedlist>
</sect2>
backend_hostname0 = 'server1'
backend_port0 = 5432
backend_weight0 = 1
-backend_data_directory0 = '/var/lib/pgsql/14/data'
+backend_data_directory0 = '/var/lib/pgsql/15/data'
backend_flag0 = 'ALLOW_TO_FAILOVER'
backend_hostname1 = 'server2'
backend_port1 = 5432
backend_weight1 = 1
-backend_data_directory1 = '/var/lib/pgsql/14/data'
+backend_data_directory1 = '/var/lib/pgsql/15/data'
backend_flag1 = 'ALLOW_TO_FAILOVER'
backend_hostname2 = 'server3'
backend_port2 = 5432
backend_weight2 = 1
-backend_data_directory2 = '/var/lib/pgsql/14/data'
+backend_data_directory2 = '/var/lib/pgsql/15/data'
backend_flag2 = 'ALLOW_TO_FAILOVER'
</programlisting>
<para>
<programlisting>
[all servers]# vi /etc/pgpool-II/failover.sh
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
[all servers]# vi /etc/pgpool-II/follow_primary.sh
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
</programlisting>
are installed in <filename>/etc/pgpool-II/</filename>. Copy these files to the data directory of the primary server (server1).
</para>
<programlisting>
-[server1]# cp -p /etc/pgpool-II/sample_scripts/recovery_1st_stage.sample /var/lib/pgsql/14/data/recovery_1st_stage
-[server1]# cp -p /etc/pgpool-II/sample_scripts/pgpool_remote_start.sample /var/lib/pgsql/14/data/pgpool_remote_start
-[server1]# chown postgres:postgres /var/lib/pgsql/14/data/{recovery_1st_stage,pgpool_remote_start}
+[server1]# cp -p /etc/pgpool-II/sample_scripts/recovery_1st_stage.sample /var/lib/pgsql/15/data/recovery_1st_stage
+[server1]# cp -p /etc/pgpool-II/sample_scripts/pgpool_remote_start.sample /var/lib/pgsql/15/data/pgpool_remote_start
+[server1]# chown postgres:postgres /var/lib/pgsql/15/data/{recovery_1st_stage,pgpool_remote_start}
</programlisting>
<para>
Basically, it should work if you change <emphasis>PGHOME</emphasis> according to PostgreSQL installation directory.
</para>
<programlisting>
-[server1]# vi /var/lib/pgsql/14/data/recovery_1st_stage
+[server1]# vi /var/lib/pgsql/15/data/recovery_1st_stage
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
-[server1]# vi /var/lib/pgsql/14/data/pgpool_remote_start
+[server1]# vi /var/lib/pgsql/15/data/pgpool_remote_start
...
-PGHOME=/usr/pgsql-14
+PGHOME=/usr/pgsql-15
...
</programlisting>
</para>
<programlisting>
wd_lifecheck_method = 'heartbeat'
- # Method of watchdog lifecheck ('heartbeat' or 'query' or 'external')
- # (change requires restart)
wd_interval = 10
- # lifecheck interval (sec) > 0
- # (change requires restart)
</programlisting>
<para>
Specify all <productname>Pgpool-II</productname> nodes information for sending and receiving heartbeat signal.
</para>
<programlisting>
heartbeat_hostname0 = 'server1'
- # Host name or IP address used
- # for sending heartbeat signal.
- # (change requires restart)
heartbeat_port0 = 9694
- # Port number used for receiving/sending heartbeat signal
- # Usually this is the same as heartbeat_portX.
- # (change requires restart)
heartbeat_device0 = ''
- # Name of NIC device (such like 'eth0')
- # used for sending/receiving heartbeat
- # signal to/from destination 0.
- # This works only when this is not empty
- # and pgpool has root privilege.
- # (change requires restart)
-
heartbeat_hostname1 = 'server2'
heartbeat_port1 = 9694
heartbeat_device1 = ''
</para>
<programlisting>
wd_heartbeat_keepalive = 2
- # Interval time of sending heartbeat signal (sec)
- # (change requires restart)
wd_heartbeat_deadtime = 30
- # Deadtime interval for heartbeat signal (sec)
- # (change requires restart)
</programlisting>
<para>
</para>
<programlisting>
wd_escalation_command = '/etc/pgpool-II/escalation.sh'
- # Executes this command at escalation on new active pgpool.
- # (change requires restart)
</programlisting>
<para>
The sample script <ulink url="https://git.postgresql.org/gitweb/?p=pgpool2.git;a=blob_plain;f=src/sample/scripts/escalation.sh.sample;hb=refs/heads/V4_4_STABLE">escalation.sh</ulink> is installed in <filename>/etc/pgpool-II/</filename>.
</para>
<programlisting>
[server1]# su - postgres
-[server1]$ /usr/pgsql-14/bin/pg_ctl start -D $PGDATA
+[server1]$ /usr/pgsql-15/bin/pg_ctl start -D $PGDATA
</programlisting>
<para>
Then let's start <productname>Pgpool-II</productname> on <literal>server1</literal>,
<literal>server1</literal>, and verify automatic failover.
</para>
<programlisting>
-[server1]$ pg_ctl -D /var/lib/pgsql/13/data -m immediate stop
+[server1]$ pg_ctl -D /var/lib/pgsql/15/data -m immediate stop
</programlisting>
<para>
After stopping <productname>PostgreSQL</productname> on <literal>server1</literal>,
projects / pgpool2.git / commitdiff