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Database-Postgresql-Centos 7安装citus集群

• 第一步：扩展依赖安装：
• 第二步：安装citus源：
• 第三步：配置postgresql源：
• 第四步：安装citus和postgresql10、postgis2.5
• 第五步：initialize a database
• 第六步：Configure connection and authentication：
• 第七步：Start database servers, create Citus and Postgis extension
• 第八步：Add worker node information
• 第九步：Verify that installation has succeeded
• 示例：

安装基于postgresql10的citus集群
三个节点，centos7.4，一个coordinator，两个worker
基础环境（ip、selinux、ssh互信等已完成）

第一步：扩展依赖安装：

yum install -y epel-release && yum update -y

第二步：安装citus源：

curl https://install.citusdata.com/community/rpm.sh | sudo bash

第三步：配置postgresql源：

vi /etc/yum.repos.d/pgdg-11-centos.repo
将11都改为10

第四步：安装citus和postgresql10、postgis2.5

#yum install -y citus74_10 此命令将安装postgresql10
#yum install -y postgis25_10 安装postgis

第五步：initialize a database

#initialize system database (using RHEL 6 vs 7 method as necessary)
sudo service postgresql-10 initdb || sudo /usr/pgsql-10/bin/postgresql-10-setup initdb
#preload citus extension
echo “shared_preload_libraries = ‘citus’” | sudo tee -a /var/lib/pgsql/10/data/postgresql.conf

第六步：Configure connection and authentication：

sudo vi /var/lib/pgsql/10/data/postgresql.conf
#Uncomment listen_addresses for the changes to take effect
listen_addresses = ‘*’

sudo vi /var/lib/pgsql/10/data/pg_hba.conf
#Allow unrestricted access to nodes in the local network. The following ranges
#correspond to 24, 20, and 16-bit blocks in Private IPv4 address spaces.
host all all 10.0.0.0/8 trust

#Also allow the host unrestricted access to connect to itself
host all all 127.0.0.1/32 trust
host all all ::1/128 trust

该实验在pg_hba.cong只执行
echo “host all all 0.0.0.0/0 trust” | sudo tee -a /var/lib/pgsql/10/data/pg_hba.conf

第七步：Start database servers, create Citus and Postgis extension

service postgresql-10 restart
chkconfig postgresql-10 on

sudo -i -u postgres psql -c “CREATE EXTENSION citus;”
sudo -i -u postgres psql -c “CREATE EXTENSION postgis;”
sudo -i -u postgres psql -c “alter user postgres with password ‘postgres’;”

以下只在coordinator节点执行

第八步：Add worker node information

sudo -i -u postgres psql -c “SELECT * from master_add_node(‘worker1’, 5432);”
sudo -i -u postgres psql -c “SELECT * from master_add_node(‘worker2’, 5432);”

第九步：Verify that installation has succeeded

[root@coordinator ~]# sudo -i -u postgres psql -c “SELECT * FROM master_get_active_worker_nodes();”
node_name | node_port
-----------±----------
worker2 | 5432
worker1 | 5432
(2 rows)

示例：

1、连接postgresql数据库，创建一张表test_table
2、配置分片策略：
SELECT master_create_distributed_table(‘test_table’, ‘id’, ‘hash’);
3、配置分片操作（将表分为2片，每个分片有两个副本）
SELECT master_create_worker_shards(‘test_table’, 2, 2);
4、装载数据
5、查看分片
SELECT * from pg_dist_shard;
6、查看分片分布
SELECT * from pg_dist_shard_placement order by shardid, placementid;