PolarDB安装

1、关闭透明大页

cat /sys/kernel/mm/transparent_hugepage/enabled

如返回结果为always madvise [never]则表示已关闭透明大页。

否则执行以下操作以关闭透明大页。

echo never > /sys/kernel/mm/transparent_hugepage/enabled

2、安装主程序

root@standby PolarDB\]# yum -y install t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64.rpm Loaded plugins: ulninfo Examining t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64.rpm: t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64 Marking t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64.rpm to be installed Resolving Dependencies --\> Running transaction check ---\> Package t-polardbx-engine.x86_64 0:8.4.19-20250825_17558853.el7 will be installed --\> Finished Dependency Resolution Dependencies Resolved ===================================================================================================================================================================================== Package Arch Version Repository Size ===================================================================================================================================================================================== Installing: t-polardbx-engine x86_64 8.4.19-20250825_17558853.el7 /t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64 2.8 G Transaction Summary ===================================================================================================================================================================================== Install 1 Package Total size: 2.8 G Installed size: 2.8 G Downloading packages: Running transaction check Running transaction test Transaction test succeeded Running transaction Installing : t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64 1/1 Copying /u01/xcluster80_20250825_current to /u01/xcluster80 Copying /u01/xcluster80_20250825_current to /u01/xcluster80_20250825 Verifying : t-polardbx-engine-8.4.19-20250825_17558853.el7.x86_64 1/1 Installed: t-polardbx-engine.x86_64 0:8.4.19-20250825_17558853.el7 Complete! 注：安装完成后，默认会创建/u01/目录，可以在u01目录下看到对应的数据库二进制文件，如下。 \[root@standby PolarDB\]# cd /u01/ \[root@standby u01\]# ll drwxr-xr-x 11 root root 4096 Apr 14 11:59 xcluster80 drwxr-xr-x 11 root root 4096 Apr 14 11:59 xcluster80_20250825 **3、创建并切换到 polardbx 用户** useradd -ms /bin/bash polardbx echo "polardbx:polardbx" \| chpasswd echo "polardbx ALL=(ALL) NOPASSWD: ALL" \>\> /etc/sudoers su - polardbx **4、配置初始化参数** 确认当前操作系统用户是 polardbx 用户，而不是 root 用户。 准备文件目录： mkdir polardbx-engine cd polardbx-engine \&\& mkdir log mysql run data tmp 准备配置文件（/home/polardbx/polardbx-engine/my.cnf），创建文件 touch my.cnf，并粘贴如下文本： $ cat my.cnf \[mysqld

basedir = /u01/xcluster80

datadir = /home/polardbx/polardbx-engine/data

tmpdir = /home/polardbx/polardbx-engine/tmp

socket = /home/polardbx/polardbx-engine/tmp/mysql.sock

log_error = /home/polardbx/polardbx-engine/log/alert.log

port = 4886

default_authentication_plugin = mysql_native_password

lower_case_table_names = 1

gtid_mode = ON

enforce_gtid_consistency = ON

log_bin = 1

sync_binlog=1

innodb_flush_log_at_trx_commit=1

log_error_verbosity = 3

mysqlx=0

enable_polarx_rpc=0

loose-mysqlx-ssl=DISABLED

ssl=0

cluster_id = 1749112302

cluster_info = 192.168.142.14:14886@1

server_id = 1001

mysqld_safe

pid_file = /home/polardbx/polardbx-engine/run/mysql.pid

5、初始化数据文件

初始化

/u01/xcluster80/bin/mysqld --defaults-file=my.cnf --initialize-insecure

检查初始化是否成功

ls -al data/* | grep lizard

...

-rw-r----- 1 polardbx polardbx 12582912 Apr 14 12:50 lizard.ibd

...

初始化正常后，可以启动或停止（以下命令使用的路径均为相对路径，请在 /home/polardbx/polardbx-engine 目录或实际 my.cnf 所在目录下执行，否则请将所有相对路径替换为绝对路径）。

启动

/u01/xcluster80/bin/mysqld_safe --defaults-file=my.cnf &

可以检查日志输出是否正常

tail -n 200 log/alert.log

停止，通过mysqladmin触发mysqld_safe和mysqld停止

/u01/xcluster80/bin/mysqladmin --defaults-file=my.cnf --socket=tmp/mysql.sock -p shutdown

6、登录数据库，验证状态（单节点启动，本机就是leader）

/u01/xcluster80/bin/mysql -h127.0.0.1 -P4886 -uroot

查询本机的paxos角色

mysql> SELECT * FROM INFORMATION_SCHEMA.ALISQL_CLUSTER_LOCAL \G

*************************** 1. row ***************************

SERVER_ID: 1

CURRENT_TERM: 2

CURRENT_LEADER: 192.168.142.14:14886

COMMIT_INDEX: 1

LAST_LOG_TERM: 2

LAST_LOG_INDEX: 1

ROLE: Leader

VOTED_FOR: 1

LAST_APPLY_INDEX: 1

SERVER_READY_FOR_RW: Yes

INSTANCE_TYPE: Normal

DISABLE_ELECTION: No

APPLY_RUNNING: No

LEADER_IP:

LEADER_PORT: 0

1 row in set (0.00 sec)

查询集群所有机器的paxos角色

mysql> SELECT * FROM INFORMATION_SCHEMA.ALISQL_CLUSTER_GLOBAL \G

*************************** 1. row ***************************

SERVER_ID: 1

IP_PORT: 192.168.142.14:14886

MATCH_INDEX: 1

NEXT_INDEX: 0

ROLE: Leader

HAS_VOTED: Yes

FORCE_SYNC: No

ELECTION_WEIGHT: 5

LEARNER_SOURCE: 0

APPLIED_INDEX: 1

PIPELINING: No

SEND_APPLIED: No