Linux环境下MariaDB如何实现负载均衡

在Linux环境下，实现MariaDB的负载均衡可以通过多种方式来完成。以下是一些常见的方法：

1. 使用MySQL Router

MySQL Router是MySQL官方提供的一个轻量级中间件，可以用于实现读写分离和负载均衡。

安装MySQL Router

sudo apt-get update
sudo apt-get install mysql-router

配置MySQL Router

创建一个配置文件/etc/mysql-router.cnf：

Linux MariaDB如何实现负载均衡

[DEFAULT]
bind-address = 0.0.0.0

[routing]
backend = readwrite://user:password@primary-db:3306,user:password@secondary-db:3306

启动MySQL Router：

sudo systemctl start mysql-router

2. 使用ProxySQL

ProxySQL是一个高性能的SQL代理，支持读写分离、负载均衡和自动故障转移。

安装ProxySQL

wget https://github.com/sysown/proxysql/releases/download/v1.7.1/proxysql_1.7.1_linux_release.tar.gz
tar zxvf proxysql_1.7.1_linux_release.tar.gz
cd proxysql_1.7.1
sudo make install

配置ProxySQL

编辑配置文件/etc/proxysql.cnf：

[mysql_servers]
primary-db = {host=primary-db, port=3306, weight=1}
secondary-db = {host=secondary-db, port=3306, weight=1}

[mysql_query_rules]
rule1 = {statement=SELECT  FROM ., destination=secondary-db}
rule2 = {statement=INSERT|UPDATE|DELETE FROM ., destination=primary-db}

[mysql_users]
user = admin
password = admin
host = 127.0.0.1
default_schema = information_schema

[system]
log_level = INFO

启动ProxySQL：

sudo systemctl start proxysql

3. 使用HAProxy

HAProxy是一个高性能的TCP/HTTP负载均衡器，也可以用于MySQL的负载均衡。

安装HAProxy

sudo apt-get update
sudo apt-get install haproxy

配置HAProxy

编辑配置文件/etc/haproxy/haproxy.cfg：

global
    log /dev/log local0
    log /dev/log local1 notice
    daemon
    maxconn 256

defaults
    log global
    mode tcp
    option tcplog
    timeout connect 5000ms
    timeout client 50000ms
    timeout server 50000ms

frontend mysql_front
    bind :3306
    default_backend mysql_back

backend mysql_back
    balance roundrobin
    server primary-db primary-db:3306 check
    server secondary-db secondary-db:3306 check

启动HAProxy：

sudo systemctl start haproxy

4. 使用Keepalived

Keepalived可以用于实现高可用性和负载均衡，结合LVS(Linux Virtual Server)可以实现更复杂的负载均衡策略。

安装Keepalived

sudo apt-get update
sudo apt-get install keepalived

配置Keepalived

编辑配置文件/etc/keepalived/keepalived.conf：

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 42
    }
    virtual_ipaddress {
        192.168.1.100
    }
}

virtual_server 192.168.1.100 3306 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    nat_mask 255.255.255.0
    persistence_timeout 50
    protocol TCP

    real_server 192.168.1.101 3306 {
        weight 1
        TCP_CHECK {
            connect_timeout 10
            connect_port 3306
        }
    }

    real_server 192.168.1.102 3306 {
        weight 1
        TCP_CHECK {
            connect_timeout 10
            connect_port 3306
        }
    }
}

启动Keepalived：

sudo systemctl start keepalived

通过以上方法，你可以在Linux环境下实现MariaDB的负载均衡。选择哪种方法取决于你的具体需求和环境。