标签：system 获取 form sed replica rest 多租户 ESS trie
Postgres-XL是一个基于PostgreSQL数据库的横向扩展开源SQL数据库集群，具有足够的灵活性来处理不同的数据库工作负载,架构如下图所示：
四台机器规划如下图所示：
禁用防火墙、selinux。各个节点通过yum安装以下软件包：
[root@pg01 ~]# yum -y install bzip2 readline-devel flex make gcc rsync另外，各个节点创建postgres用户：
[root@pg01 ~]# groupadd postgres;useradd -g postgres postgres;echo redhat|passwd --stdin postgres用户创建完成后，还需要在各个节点配置postgres用户的免密码登录(略)。然后编辑postgres用户的环境变量，加入如下内容：
[root@pg01 ~]# mkdir /u01;chown postgres:postgres /u01
[root@pg01 ~]# su - postgres
[postgres@pg01 ~]$ vi .bashrc
export PGUSER=postgres
export PGHOME=/usr/local/pgsql
export PGXC_CTL_HOME=/u01/pgxl/pgxc_ctl
export LD_LIBRARY_PATH=$PGHOME/lib
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/lib:/usr/lib:/usr/local/lib
export PATH=$PGHOME/bin:$PATH:$HOME/.local/bin:$HOME/bin在各个节点以root用户进行安装，默认的安装目录是/usr/local/pgsql。
[root@pg01 ~]# wget https://×××w.postgres-xl.org/downloads/postgres-xl-10r1.tar.gz;tar -xzf postgres-xl-10r1.tar.gz;cd postgres-xl-10r1;./configure&&make&&make install
[root@pg01 postgres-xl-10r1]# cd contrib;make && make install在一个节点操作即可。
[postgres@pg01 ~]$ pgxc_ctl
PGXC prepare
PGXC exit编辑生成的配置文件，内容如下：
pgxcInstallDir=/u01
pgxcOwner=$USER
pgxcUser=$pgxcOwner
tmpDir=/tmp
localTmpDir=$tmpDir
#--------GTM Master--------
gtmName=gtm_master
gtmMasterServer=pg01
gtmMasterPort=20001
gtmMasterDir=$pgxcInstallDir/pgxl/nodes/gtm
gtmExtraConfig=none
gtmMasterSpecificExtraConfig=none
#-------GTM Slave---------
gtmSlave=y
gtmSlaveName=gtm_slave
gtmSlaveServer=pg02
gtmSlavePort=20001
gtmSlaveDir=$pgxcInstallDir/pgxl/nodes/gtm_slave
gtmSlaveSpecificExtraConfig=none
#-------GTM Proxy--------
gtmProxyDir=$pgxcInstallDir/pgxl/nodes/gtm_pxy
gtmProxy=y
gtmProxyNames=(gtm_pxy1 gtm_pxy2)
gtmProxyServers=(pg01 pg02)
gtmProxyPorts=(20002 20002)
gtmProxyDirs=($gtmProxyDir $gtmProxyDir)
gtmPxyExtraConfig=none
gtmPxySpecificExtraConfig=(none none)
#-----Coordinators Master----------
coordMasterDir=$pgxcInstallDir/pgxl/nodes/coord
coordSlaveDir=$pgxcInstallDir/pgxl/nodes/coord_slave
coordArchLogDir=$pgxcInstallDir/pgxl/nodes/coord_archlog
coordNames=(coord1 coord2)
coordPorts=(5433 5433)
poolerPorts=(5434 5434)
coordPgHbaEntries=(0.0.0.0/0)
coordMasterServers=(pg01 pg02)
coordMasterDirs=($coordMasterDir $coordMasterDir)
coordMaxWALsernder=5
coordMaxWALSenders=($coordMaxWALsernder $coordMaxWALsernder)
#-----Coordinators Slave----------
coordSlave=y
coordSlaveSync=y
coordSlaveServers=(pg03 pg04)
coordSlavePorts=(5433 5433)
coordSlavePoolerPorts=(5434 5434)
coordSlaveDirs=($coordSlaveDir $coordSlaveDir)
coordArchLogDirs=($coordArchLogDir $coordArchLogDir)
coordExtraConfig=coordExtraConfig
cat > $coordExtraConfig <<EOF
log_destination = ‘stderr‘
logging_collector = on
log_directory = ‘pg_log‘
listen_addresses = ‘*‘
max_connections = 1000
EOF
coordSpecificExtraConfig=(none none)
coordExtraPgHba=none
coordSpecificExtraPgHba=(none none)
#------Datanodes Master----------
datanodeMasterDir=$pgxcInstallDir/pgxl/nodes/dnmaster
datanodeSlaveDir=$pgxcInstallDir/pgxl/nodes/dnslave
datanodeArchLogDir=$pgxcInstallDir/pgxl/nodes/dn_archlog
primaryDatanode=pg03
datanodeNames=(datanode1 datanode2)
datanodePorts=(5436 5436)
datanodePoolerPorts=(5437 5437)
datanodePgHbaEntries=(0.0.0.0/0)
datanodeMasterServers=(pg03 pg04)
datanodeMasterDirs=($datanodeMasterDir $datanodeMasterDir)
datanodeMaxWalSender=0
datanodeMaxWALSenders=($datanodeMaxWalSender $datanodeMaxWalSender)
datanodeSlave=n初始化完成后，会自动启动集群。
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf init all
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
Initialize GTM master
The files belonging to this GTM system will be owned by user "postgres".
This user must also own the server process.
fixing permissions on existing directory /u01/pgxl/nodes/gtm ... ok
creating configuration files ... ok
creating control file ... ok
Success.
Done.
Start GTM master
server starting
Initialize GTM slave
The files belonging to this GTM system will be owned by user "postgres".
This user must also own the server process.
fixing permissions on existing directory /u01/pgxl/nodes/gtm_slave ... ok
creating configuration files ... ok
creating control file ... ok
Success.
Done.
Start GTM slavepgxc_ctl(13032):1811220924_48 server starting
Done.
Initialize all the gtm proxies.
Initializing gtm proxy gtm_pxy1.
Initializing gtm proxy gtm_pxy2.
The files belonging to this GTM system will be owned by user "postgres".
This user must also own the server process.
fixing permissions on existing directory /u01/pgxl/nodes/gtm_pxy ... ok
creating configuration files ... ok
Success.
The files belonging to this GTM system will be owned by user "postgres".
This user must also own the server process.
fixing permissions on existing directory /u01/pgxl/nodes/gtm_pxy ... ok
creating configuration files ... ok
Success.
Done.
Starting all the gtm proxies.
Starting gtm proxy gtm_pxy1.
Starting gtm proxy gtm_pxy2.
server starting
server starting
Done.
Initialize all the coordinator masters.
Initialize coordinator master coord1.
Initialize coordinator master coord2.
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale "en_US.UTF-8".
The default database encoding has accordingly been set to "UTF8".
The default text search configuration will be set to "english".
Data page checksums are disabled.
fixing permissions on existing directory /u01/pgxl/nodes/coord ... ok
creating subdirectories ... ok
selecting default max_connections ... 100
selecting default shared_buffers ... 128MB
selecting dynamic shared memory implementation ... posix
creating configuration files ... ok
running bootstrap script ... ok
performing post-bootstrap initialization ... creating cluster information ... ok
syncing data to disk ... ok
freezing database template0 ... ok
freezing database template1 ... ok
freezing database postgres ... ok
WARNING: enabling "trust" authentication for local connections
You can change this by editing pg_hba.conf or using the option -A, or
--auth-local and --auth-host, the next time you run initdb.
Success.
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale "en_US.UTF-8".
The default database encoding has accordingly been set to "UTF8".
The default text search configuration will be set to "english".
Data page checksums are disabled.
fixing permissions on existing directory /u01/pgxl/nodes/coord ... ok
creating subdirectories ... ok
selecting default max_connections ... 100
selecting default shared_buffers ... 128MB
selecting dynamic shared memory implementation ... posix
creating configuration files ... ok
running bootstrap script ... ok
performing post-bootstrap initialization ... creating cluster information ... ok
syncing data to disk ... ok
freezing database template0 ... ok
freezing database template1 ... ok
freezing database postgres ... ok
WARNING: enabling "trust" authentication for local connections
You can change this by editing pg_hba.conf or using the option -A, or
--auth-local and --auth-host, the next time you run initdb.
Success.
Done.
Starting coordinator master.
Starting coordinator master coord1
Starting coordinator master coord2
2018-11-22 09:24:59.252 CST [13950] LOG: listening on IPv4 address "0.0.0.0", port 5433
2018-11-22 09:24:59.252 CST [13950] LOG: listening on IPv6 address "::", port 5433
2018-11-22 09:24:59.254 CST [13950] LOG: listening on Unix socket "/tmp/.s.PGSQL.5433"
2018-11-22 09:24:59.302 CST [13950] LOG: redirecting log output to logging collector process
2018-11-22 09:24:59.302 CST [13950] HINT: Future log output will appear in directory "pg_log".
2018-11-22 09:24:59.060 CST [13633] LOG: listening on IPv4 address "0.0.0.0", port 5433
2018-11-22 09:24:59.061 CST [13633] LOG: listening on IPv6 address "::", port 5433
2018-11-22 09:24:59.062 CST [13633] LOG: listening on Unix socket "/tmp/.s.PGSQL.5433"
2018-11-22 09:24:59.109 CST [13633] LOG: redirecting log output to logging collector process
2018-11-22 09:24:59.109 CST [13633] HINT: Future log output will appear in directory "pg_log".
Done.
Initialize all the coordinator slaves.
Initialize the coordinator slave coord1.
Initialize the coordinator slave coord2.
Done.
Starting all the coordinator slaves.
Starting coordinator slave coord1.
Starting coordinator slave coord2.
2018-11-22 09:25:05.987 CST [13330] LOG: listening on IPv4 address "0.0.0.0", port 5433
2018-11-22 09:25:05.987 CST [13330] LOG: listening on IPv6 address "::", port 5433
2018-11-22 09:25:05.989 CST [13330] LOG: listening on Unix socket "/tmp/.s.PGSQL.5433"
2018-11-22 09:25:06.039 CST [13330] LOG: redirecting log output to logging collector process
2018-11-22 09:25:06.039 CST [13330] HINT: Future log output will appear in directory "pg_log".
2018-11-22 09:25:05.517 CST [13266] LOG: listening on IPv4 address "0.0.0.0", port 5433
2018-11-22 09:25:05.517 CST [13266] LOG: listening on IPv6 address "::", port 5433
2018-11-22 09:25:05.518 CST [13266] LOG: listening on Unix socket "/tmp/.s.PGSQL.5433"
2018-11-22 09:25:05.567 CST [13266] LOG: redirecting log output to logging collector process
2018-11-22 09:25:05.567 CST [13266] HINT: Future log output will appear in directory "pg_log".
Done
Initialize all the datanode masters.
Initialize the datanode master datanode1.
Initialize the datanode master datanode2.
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale "en_US.UTF-8".
The default database encoding has accordingly been set to "UTF8".
The default text search configuration will be set to "english".
Data page checksums are disabled.
fixing permissions on existing directory /u01/pgxl/nodes/dnmaster ... ok
creating subdirectories ... ok
selecting default max_connections ... 100
selecting default shared_buffers ... 128MB
selecting dynamic shared memory implementation ... posix
creating configuration files ... ok
running bootstrap script ... ok
performing post-bootstrap initialization ... creating cluster information ... ok
syncing data to disk ... ok
freezing database template0 ... ok
freezing database template1 ... ok
freezing database postgres ... ok
WARNING: enabling "trust" authentication for local connections
You can change this by editing pg_hba.conf or using the option -A, or
--auth-local and --auth-host, the next time you run initdb.
Success.
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale "en_US.UTF-8".
The default database encoding has accordingly been set to "UTF8".
The default text search configuration will be set to "english".
Data page checksums are disabled.
fixing permissions on existing directory /u01/pgxl/nodes/dnmaster ... ok
creating subdirectories ... ok
selecting default max_connections ... 100
selecting default shared_buffers ... 128MB
selecting dynamic shared memory implementation ... posix
creating configuration files ... ok
running bootstrap script ... ok
performing post-bootstrap initialization ... creating cluster information ... ok
syncing data to disk ... ok
freezing database template0 ... ok
freezing database template1 ... ok
freezing database postgres ... ok
WARNING: enabling "trust" authentication for local connections
You can change this by editing pg_hba.conf or using the option -A, or
--auth-local and --auth-host, the next time you run initdb.
Success.
Done.
Starting all the datanode masters.
Starting datanode master datanode1.
Starting datanode master datanode2.
2018-11-22 09:25:15.129 CST [13604] LOG: listening on IPv4 address "0.0.0.0", port 5436
2018-11-22 09:25:15.130 CST [13604] LOG: listening on IPv6 address "::", port 5436
2018-11-22 09:25:15.131 CST [13604] LOG: listening on Unix socket "/tmp/.s.PGSQL.5436"
2018-11-22 09:25:15.148 CST [13604] LOG: redirecting log output to logging collector process
2018-11-22 09:25:15.148 CST [13604] HINT: Future log output will appear in directory "pg_log".
2018-11-22 09:25:14.657 CST [13539] LOG: listening on IPv4 address "0.0.0.0", port 5436
2018-11-22 09:25:14.657 CST [13539] LOG: listening on IPv6 address "::", port 5436
2018-11-22 09:25:14.659 CST [13539] LOG: listening on Unix socket "/tmp/.s.PGSQL.5436"
2018-11-22 09:25:14.676 CST [13539] LOG: redirecting log output to logging collector process
2018-11-22 09:25:14.676 CST [13539] HINT: Future log output will appear in directory "pg_log".
Done.
ALTER NODE coord1 WITH (HOST=‘pg01‘, PORT=5433);
ALTER NODE
CREATE NODE coord2 WITH (TYPE=‘coordinator‘, HOST=‘pg02‘, PORT=5433);
CREATE NODE
CREATE NODE datanode1 WITH (TYPE=‘datanode‘, HOST=‘pg03‘, PORT=5436);
CREATE NODE
CREATE NODE datanode2 WITH (TYPE=‘datanode‘, HOST=‘pg04‘, PORT=5436);
CREATE NODE
SELECT pgxc_pool_reload();
pgxc_pool_reload
------------------
t
(1 row)
CREATE NODE coord1 WITH (TYPE=‘coordinator‘, HOST=‘pg01‘, PORT=5433);
CREATE NODE
ALTER NODE coord2 WITH (HOST=‘pg02‘, PORT=5433);
ALTER NODE
CREATE NODE datanode1 WITH (TYPE=‘datanode‘, HOST=‘pg03‘, PORT=5436);
CREATE NODE
CREATE NODE datanode2 WITH (TYPE=‘datanode‘, HOST=‘pg04‘, PORT=5436);
CREATE NODE
SELECT pgxc_pool_reload();
pgxc_pool_reload
------------------
t
(1 row)
Done.
EXECUTE DIRECT ON (datanode1) ‘CREATE NODE coord1 WITH (TYPE=‘‘coordinator‘‘, HOST=‘‘pg01‘‘, PORT=5433)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode1) ‘CREATE NODE coord2 WITH (TYPE=‘‘coordinator‘‘, HOST=‘‘pg02‘‘, PORT=5433)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode1) ‘ALTER NODE datanode1 WITH (TYPE=‘‘datanode‘‘, HOST=‘‘pg03‘‘, PORT=5436)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode1) ‘CREATE NODE datanode2 WITH (TYPE=‘‘datanode‘‘, HOST=‘‘pg04‘‘, PORT=5436)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode1) ‘SELECT pgxc_pool_reload()‘;
pgxc_pool_reload
------------------
t
(1 row)
EXECUTE DIRECT ON (datanode2) ‘CREATE NODE coord1 WITH (TYPE=‘‘coordinator‘‘, HOST=‘‘pg01‘‘, PORT=5433)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode2) ‘CREATE NODE coord2 WITH (TYPE=‘‘coordinator‘‘, HOST=‘‘pg02‘‘, PORT=5433)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode2) ‘CREATE NODE datanode1 WITH (TYPE=‘‘datanode‘‘, HOST=‘‘pg03‘‘, PORT=5436)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode2) ‘ALTER NODE datanode2 WITH (TYPE=‘‘datanode‘‘, HOST=‘‘pg04‘‘, PORT=5436)‘;
EXECUTE DIRECT
EXECUTE DIRECT ON (datanode2) ‘SELECT pgxc_pool_reload()‘;
pgxc_pool_reload
------------------
t
(1 row)
Done.通过查询pgxc_node表可以获取集群节点信息：
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf stop all
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf start all2.4 Posgres-XL集群服务监控
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf monitor all
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
Running: gtm master
Running: gtm slave
Running: gtm proxy gtm_pxy1
Running: gtm proxy gtm_pxy2
Running: coordinator master coord1
Running: coordinator slave coord1
Running: coordinator master coord2
Running: coordinator slave coord2
Running: datanode master datanode1
Running: datanode slave datanode1
Running: datanode master datanode2
Running: datanode slave datanode2创建一张log表，然后插入500条数据，如下：
[postgres@pg01 ~]$ psql -p5433
psql (PGXL 10r1, based on PG 10.5 (Postgres-XL 10r1))
Type "help" for help.
postgres=# CREATE TABLE log (id numeric NOT NULL,stamp timestamp with time zone,user_id numeric);
postgres=# copy log from ‘/u02/tmp/log.csv‘ with csv;
COPY 499可以在协调器节点或者各个数据节点查看，这里使用下面的语句直接统计每个数据节点的表数据分布情况：
postgres=# SELECT xc_node_id, count(*) FROM log GROUP BY xc_node_id;
postgres=# CREATE TABLE log (id numeric NOT NULL,stamp timestamp with time zone,user_id numeric) distribute by hash(id);distribute表数据分布如下图：
postgres=# CREATE TABLE log2 (id numeric NOT NULL,stamp timestamp with time zone,user_id numeric) distribute by replication;
postgres=# copy log2 from ‘/u02/tmp/log.csv‘ with csv;replication表数据分布如下图：
不论在哪个数据节点查询，显示的结果都一样的。
为了提高集群可用性，以下配置数据节点的热备以便进行故障转移切换。
在gtm节点操作，新增两个slave数据节点，如下：
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
PGXC add datanode slave datanode1 pg05 5436 5437 /u01/pgxl/nodes/dnslave /u01/pgxl/nodes/dn_slave_war /u01/pgxl/nodes/dn_archlog
PGXC add datanode slave datanode2 pg06 5436 5437 /u01/pgxl/nodes/dnslave /u01/pgxl/nodes/dn_slave_war /u01/pgxl/nodes/dn_archlog检查所有服务运行正常:
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf monitor all
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
Running: gtm master
Running: gtm slave
Running: gtm proxy gtm_pxy1
Running: gtm proxy gtm_pxy2
Running: coordinator master coord1
Running: coordinator slave coord1
Running: coordinator master coord2
Running: coordinator slave coord2
Running: datanode master datanode1
Running: datanode slave datanode1
Running: datanode master datanode2
Running: datanode slave datanode2当前的主节点是pg03和pg04，如下图：
切换主备节点：
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf monitor all
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
Running: gtm master
Running: gtm slave
Running: gtm proxy gtm_pxy1
Running: gtm proxy gtm_pxy2
Running: coordinator master coord1
Running: coordinator slave coord1
Running: coordinator master coord2
Running: coordinator slave coord2
Running: datanode master datanode1
Running: datanode slave datanode1
Running: datanode master datanode2
Running: datanode slave datanode2
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf failover datanode datanode1 datanode2
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
Failover specified datanodes.
Failover the datanode datanode1.
Failover datanode datanode1 using GTM itself
Actual Command: ssh postgres@pg05 "( pg_ctl promote -Z datanode -D /u01/pgxl/nodes/dnslave ) > /tmp/pg01_STDOUT_4264_0 2>&1" < /dev/null > /dev/null 2>&1
Bring remote stdout: scp postgres@pg05:/tmp/pg01_STDOUT_4264_0 /tmp/STDOUT_4264_1 > /dev/null 2>&1
Actual Command: ssh postgres@pg05 "( pg_ctl restart -w -Z datanode -D /u01/pgxl/nodes/dnslave -o -i; sleep 1 ) > /tmp/pg01_STDOUT_4264_2 2>&1" < /dev/null > /dev/null 2>&1
Bring remote stdout: scp postgres@pg05:/tmp/pg01_STDOUT_4264_2 /tmp/STDOUT_4264_3 > /dev/null 2>&1
2018-11-23 14:52:34.655 CST [26323] LOG: listening on IPv4 address "0.0.0.0", port 5436
2018-11-23 14:52:34.655 CST [26323] LOG: listening on IPv6 address "::", port 5436
2018-11-23 14:52:34.657 CST [26323] LOG: listening on Unix socket "/tmp/.s.PGSQL.5436"
2018-11-23 14:52:34.675 CST [26323] LOG: redirecting log output to logging collector process
2018-11-23 14:52:34.675 CST [26323] HINT: Future log output will appear in directory "pg_log".
ALTER NODE
pgxc_pool_reload
------------------
t
(1 row)
EXECUTE DIRECT
pgxc_pool_reload
------------------
t
(1 row)
EXECUTE DIRECT
pgxc_pool_reload
------------------
t
(1 row)
ALTER NODE
pgxc_pool_reload
------------------
t
(1 row)
Failover the datanode datanode2.
Failover datanode datanode2 using GTM itself
Actual Command: ssh postgres@pg06 "( pg_ctl promote -Z datanode -D /u01/pgxl/nodes/dnslave ) > /tmp/pg01_STDOUT_4264_4 2>&1" < /dev/null > /dev/null 2>&1
Bring remote stdout: scp postgres@pg06:/tmp/pg01_STDOUT_4264_4 /tmp/STDOUT_4264_5 > /dev/null 2>&1
Actual Command: ssh postgres@pg06 "( pg_ctl restart -w -Z datanode -D /u01/pgxl/nodes/dnslave -o -i; sleep 1 ) > /tmp/pg01_STDOUT_4264_6 2>&1" < /dev/null > /dev/null 2>&1
Bring remote stdout: scp postgres@pg06:/tmp/pg01_STDOUT_4264_6 /tmp/STDOUT_4264_7 > /dev/null 2>&1
2018-11-23 14:52:38.607 CST [26317] LOG: listening on IPv4 address "0.0.0.0", port 5436
2018-11-23 14:52:38.607 CST [26317] LOG: listening on IPv6 address "::", port 5436
2018-11-23 14:52:38.609 CST [26317] LOG: listening on Unix socket "/tmp/.s.PGSQL.5436"
2018-11-23 14:52:38.628 CST [26317] LOG: redirecting log output to logging collector process
2018-11-23 14:52:38.628 CST [26317] HINT: Future log output will appear in directory "pg_log".
ALTER NODE
pgxc_pool_reload
------------------
t
(1 row)
EXECUTE DIRECT
pgxc_pool_reload
------------------
t
(1 row)
EXECUTE DIRECT
pgxc_pool_reload
------------------
t
(1 row)
ALTER NODE
pgxc_pool_reload
------------------
t
(1 row)
Done.
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf monitor all
/bin/bash
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Installing pgxc_ctl_bash script as /u01/pgxl/pgxc_ctl_bash.
Reading configuration using /u01/pgxl/pgxc_ctl_bash --home /u01/pgxl --configuration /u01/pgxl/pgxc_ctl/pgxc_ctl.conf
Finished reading configuration.
******** PGXC_CTL START ***************
Current directory: /u01/pgxl
Running: gtm master
Running: gtm slave
Running: gtm proxy gtm_pxy1
Running: gtm proxy gtm_pxy2
Running: coordinator master coord1
Running: coordinator slave coord1
Running: coordinator master coord2
Running: coordinator slave coord2
Running: datanode master datanode1
Running: datanode master datanode2切换完成后，旧的master节点作废，而新建的两个slave节点就转变为master节点角色。
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf remove datanode slave datanode1 clean
[postgres@pg01 ~]$ pgxc_ctl -c /u01/pgxl/pgxc_ctl/pgxc_ctl.conf remove datanode slave datanode2 clean标签：system 获取 form sed replica rest 多租户 ESS trie
原文地址：http://blog.51cto.com/candon123/2322012
