部署tomcat单机多实例，keepalived+mysql的互为主从高可用，mysql+keepalived高可用

部署tomcat单机多实例

在Tomcat中部署单机多实例是一种常见的做法，它允许您在同一台服务器上运行多个独立的Tomcat实例，每个实例都有自己的配置、日志和应用程序。

安装jdk环境

首先配置java环境
[root@tomcat ~]# tar xf  jdk-8u211-linux-x64.tar.gz -C /usr/local改名，设置环境变量
[root@tomcat ~]# cd /usr/local
[root@tomcat local]# mv jdk1.8.0_211/ java
[root@tomcat local]# vim  /etc/profile.d/java.shJAVA_HOME=/usr/local/java
PATH=$PATH:$JAVA_HOME/bin重载环境变量
[root@tomcat local]# source /etc/profile.d/java.sh 
查看jdk是否安装成功
[root@tomcat local]# java -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)

安装tomcat

解压 
[root@tomcat ~]# tar xf apache-tomcat-8.5.92.tar.gz -C /usr/local进入
[root@tomcat ~]# cd /usr/local
改名
[root@tomcat local]# mv  apache-tomcat-8.5.92 tomcat复制
[root@tomcat local]# cp -r tomcat tomcat-2
[root@tomcat local]# cp -r tomcat tomcat-3

配置文件

tomcat

修改配置文件
tomcat
[root@tomcat local]# vim ./tomcat/conf/server.xml

tomcat-2

[root@tomcat local]# vim ./tomcat-2/conf/server.xml

tomcat-3

[root@tomcat local]# vim ./tomcat-3/conf/server.xml

启动tomcat

[root@tomcat local]# ./tomcat/bin/startup.sh 
Using CATALINA_BASE:   /usr/local/tomcat
Using CATALINA_HOME:   /usr/local/tomcat
Using CATALINA_TMPDIR: /usr/local/tomcat/temp
Using JRE_HOME:        /usr/local/java
Using CLASSPATH:       /usr/local/tomcat/bin/bootstrap.jar:/usr/local/tomcat/bin/tomcat-juli.jar
Using CATALINA_OPTS:   
Tomcat started.[root@tomcat local]# ./tomcat-2/bin/startup.sh 
Using CATALINA_BASE:   /usr/local/tomcat-2
Using CATALINA_HOME:   /usr/local/tomcat-2
Using CATALINA_TMPDIR: /usr/local/tomcat-2/temp
Using JRE_HOME:        /usr/local/java
Using CLASSPATH:       /usr/local/tomcat-2/bin/bootstrap.jar:/usr/local/tomcat-2/bin/tomcat-juli.jar
Using CATALINA_OPTS:   
Tomcat started.[root@tomcat local]# ./tomcat-3/bin/startup.sh 
Using CATALINA_BASE:   /usr/local/tomcat-3
Using CATALINA_HOME:   /usr/local/tomcat-3
Using CATALINA_TMPDIR: /usr/local/tomcat-3/temp
Using JRE_HOME:        /usr/local/java
Using CLASSPATH:       /usr/local/tomcat-3/bin/bootstrap.jar:/usr/local/tomcat-3/bin/tomcat-juli.jar
Using CATALINA_OPTS:   
Tomcat started.

查看端口

[root@tomcat local]# ss -nplt
State       Recv-Q Send-Q                                        Local Address:Port                                                       Peer Address:Port              
LISTEN      0      128                                                       *:22                                                                    *:*                   users:(("sshd",pid=920,fd=3))
LISTEN      0      100                                               127.0.0.1:25                                                                    *:*                   users:(("master",pid=1148,fd=13))
LISTEN      0      1                                        [::ffff:127.0.0.1]:8005                                                               [::]:*                   users:(("java",pid=1902,fd=61))
LISTEN      0      1                                        [::ffff:127.0.0.1]:8006                                                               [::]:*                   users:(("java",pid=2043,fd=61))
LISTEN      0      1                                        [::ffff:127.0.0.1]:8007                                                               [::]:*                   users:(("java",pid=2095,fd=61))
LISTEN      0      80                                                     [::]:3306                                                               [::]:*                   users:(("mysqld",pid=1004,fd=29))
LISTEN      0      100                                                    [::]:8080                                                               [::]:*                   users:(("java",pid=1902,fd=52))
LISTEN      0      100                                                    [::]:8081                                                               [::]:*                   users:(("java",pid=2043,fd=52))
LISTEN      0      100                                                    [::]:8082                                                               [::]:*                   users:(("java",pid=2095,fd=52))
LISTEN      0      128

访问实例

keepalived+mysql互为主从的高可用

IP1：10.36.192.223 安装msyql

IP2：10.36.192.222 安装mysql

首先做IP1为主，IP2为从

IP1的操作

IP1的操作
[root@IP1 ~]# mkdir /var/log/mysql
[root@IP1 ~]# chown  -R mysql.mysql /var/log/mysqlvim /etc/my.cnf
###
log-bin=/var/log/mysql/mysql-bin       #启用二进制文件日志记录
server-id=1 
###
重启mysql
# systemctl restart mysqld

登录数据库
创建主从登录的用户
mysql> grant replication slave on *.* to  'zc'@'%' identified by 'Qianfeng@123';刷新
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)查看二进制日志
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      587 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

IP2的操作

[root@IP2 ~]# mkdir /var/log/mysql
[root@IP2 ~]# chown  -R mysql.mysql /var/log/mysqlvim /etc/my.cnf
###
server-id=2重启msyql
# systemctl restart mysqld
登录数据库
mysql> CHANGE MASTER TO->   MASTER_HOST='10.36.192.223',->   MASTER_USER='zc',->   MASTER_PASSWORD='Qianfeng@123',->   MASTER_PORT=3306,->   MASTER_LOG_FILE='mysql-bin.000001',->   MASTER_LOG_POS=587,->   MASTER_CONNECT_RETRY=10;
Query OK, 0 rows affected, 2 warnings (0.01 sec)mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)启动主从，查看主从状态
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)mysql> show slave status\G;
*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 10.36.192.223Master_User: zcMaster_Port: 3306Connect_Retry: 10Master_Log_File: mysql-bin.000001Read_Master_Log_Pos: 587Relay_Log_File: slave-relay-bin.000002Relay_Log_Pos: 320Relay_Master_Log_File: mysql-bin.000001Slave_IO_Running: YesSlave_SQL_Running: Yes

做IP2为主，IP1为从

IP2的操作

vim /etc/my.cnf
###
添加第二行
[mysqld]
log-bin=/var/log/mysql/mysql-bin       #启用二进制文件日志记录重启mysql
# systemctl restart mysqld登录数据库创建主从登录的用户
mysql> grant replication slave on *.* to  'zxd'@'%' identified by 'Qianfeng@123';
Query OK, 0 rows affected, 1 warning (0.00 sec)mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)查看二进制日志坐标
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      154 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

IP1的操作

mysql> CHANGE MASTER TO->   MASTER_HOST='10.36.192.222',->   MASTER_USER='zxd',->   MASTER_PASSWORD='Qianfeng@123',->   MASTER_PORT=3306,->   MASTER_LOG_FILE='mysql-bin.000001',->   MASTER_LOG_POS=154,->   MASTER_CONNECT_RETRY=10;
Query OK, 0 rows affected, 2 warnings (0.01 sec)刷新
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)启动主从
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)查看主从状态
mysql> show slave status\G;
*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 10.36.192.222Master_User: zxdMaster_Port: 3306Connect_Retry: 10Master_Log_File: mysql-bin.000001Read_Master_Log_Pos: 154Relay_Log_File: master-relay-bin.000002Relay_Log_Pos: 320Relay_Master_Log_File: mysql-bin.000001Slave_IO_Running: YesSlave_SQL_Running: Yes

互为主从成功配置

在IP1的数据库创库，IP2也可以看到

IP1
mysql> create database zhangxiaodong;
Query OK, 1 row affected (0.00 sec)mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| zhangxiaodong      |
+--------------------+
5 rows in set (0.00 sec)IP2
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| zhangxiaodong      |
+--------------------+
5 rows in set (0.00 sec)

安装keepalived

IP1  IP2都操作
# yum -y install keepalived

编写当某一台的MySQL停掉以后，就自动停掉那台机器的keepalived服务的脚本

cd /etc/keepalived
[root@IP1 keepalived]# cat keepalived_check_mysql.sh 
#!/bin/bash
/usr/bin/mysql -uroot -p'Qianfeng@123' -e "show status" &>/dev/null
if [ $? -ne 0 ] ;then
#	service keepalived stopsystemctl stop keepalived
ficd /etc/keepalived
[root@IP2 keepalived]# cat keepalived_check_mysql.sh 
#!/bin/bash
/usr/bin/mysql -uroot -p'Qianfeng@123' -e "show status" &>/dev/null
if [ $? -ne 0 ] ;then
#	service keepalived stopsystemctl stop keepalived
fi

给脚本执行权限

chmod a+x keepalived_check_mysql.sh

在keepalived的配置文件中引用脚本

IP1
[root@IP1  keepalived]# cat keepalived.conf 
! Configuration File for keepalivedglobal_defs {router_id directory1 
}
vrrp_script check_run {script "/etc/keepalived/keepalived_check_mysql.sh"interval 5
}vrrp_instance VI_1 {state MASTERinterface ens33virtual_router_id 66priority 100advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {10.36.192.233/24}track_script {check_run}
}
IP2
[root@IP2 keepalived]# cat keepalived.conf 
! Configuration File for keepalivedglobal_defs {router_id directory2
}
vrrp_script check_run {script "/etc/keepalived/keepalived_check_mysql.sh"interval 5
}vrrp_instance VI_1 {state BACKUPnopreemptinterface ens33virtual_router_id 66priority 50advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {10.36.192.233/24}track_script {#check_runcheck_run}
}

启动keepqlived

#systemctl start keepalived

[root@IP1 keepalived]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:99:b8:b4 brd ff:ff:ff:ff:ff:ffinet 10.36.192.223/24 brd 10.36.192.255 scope global noprefixroute dynamic ens33valid_lft 255232sec preferred_lft 255232secinet 10.36.192.233/24 scope global secondary ens33valid_lft forever preferred_lft forever

此时的虚拟IP为10.36.192.233，在IP1上，但由于互为主从，因此查到数据相同

在那俩台数据库都创建可以允许远程登录数据库的用户

IP1
mysql> grant all on *.* to 'malong'@'%' identified by 'Qianfeng@123!';
Query OK, 0 rows affected, 1 warning (0.00 sec)IP2
mysql> grant all on *.* to 'malong'@'%' identified by 'Qianfeng@123!';
Query OK, 0 rows affected, 1 warning (0.00 sec)

准备另一台机器，做测试实验

[root@mysql ~]# mysql -umalong -pQianfeng@123! -h10.36.192.233 
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 15
Server version: 5.7.42-log MySQL Community Server (GPL)Copyright (c) 2000, 2023, Oracle and/or its affiliates.Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| zhangxiaodong      |
+--------------------+
5 rows in set (0.00 sec)

经过测试发现，当IP1的数据库停掉以后，keepalived也会停掉，此时虚拟IP会飘向IP2的机器上，但是由于俩台数据库是互为主从，因此测试机器登上去查看到的数据是相同的.这样可以保证数据库的高可用.

MySQL+keepalived高可用

实验机器IP
master（干净机器）10.36.192.223        
slave （干净机器）10.36.192.222
测试（已有MySQL）10.36.192.199

俩台服务器都安装mysql，keepalived，并修改mysql初始密码

[root@master ~]# yum install -y mysql-server keepalived[root@master ~]# systemctl restart mysqld[root@master ~]# grep "password" /var/log/mysqld.log2023-11-02T07:46:28.937422Z 1 [Note] A temporary password is generated for root@localhost: fB#sVi1UyRW;[root@master ~]# mysqladmin -uroot -p'fB#sVi1UyRW;' password 'Qianfeng@123'
[root@slave ~]# yum install -y mysql-server keepalived[root@slave ~]# systemctl restart mysqld[root@slave ~]# grep "password" /var/log/mysqld.log2023-11-02T07:46:28.937422Z 1 [Note] A temporary password is generated for root@localhost: ?Huo=g>tQ9tn;[root@slave ~]# mysqladmin -uroot -p'?Huo=g>tQ9tn' password 'Qianfeng@123'

登录俩台数据库创建允许远程登录的用户

[root@master ~]# mysql -uroot -p'Qianfeng@123'
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
...mysql> grant all on *.* to 'malong'@'%' identified by 'Qianfeng@123!';
Query OK, 0 rows affected, 1 warning (0.00 sec)mysql> \q
Bye[root@slave ~]# mysql -uroot -p'Qianfeng@123'
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
...mysql> grant all on *.* to 'malong'@'%' identified by 'Qianfeng@123!';
Query OK, 0 rows affected, 1 warning (0.00 sec)mysql> \q
Bye

在master的数据库创建一个库

create database dbtest；

master配置keepalived

[root@master ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalivedglobal_defs {router_id directory1 
}
vrrp_instance VI_1 {state MASTERinterface ens33virtual_router_id 66priority 100advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {10.36.192.233/24   ###虚拟的IP}
}

slave配置keepalived

[root@slave ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {router_id directory2
}
vrrp_instance VI_1 {state BACKUPnopreemptinterface ens33virtual_router_id 66priority 50advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {10.36.192.233/24}
}

配置数据库检查脚本

[root@master keepalived]# cat keepalived_check_mysql.sh 
#!/bin/bash
/usr/bin/mysql -uroot -p'Qianfeng@123' -e "show status" &>/dev/null
if [ $? -ne 0 ] ;then
#	service keepalived stopsystemctl stop keepalived
fi[root@slave keepalived]# cat keepalived_check_mysql.sh 
#!/bin/bash
/usr/bin/mysql -uroot -p'Qianfeng@123' -e "show status" &>/dev/null
if [ $? -ne 0 ] ;then
#	service keepalived stopsystemctl stop keepalived
fi

记得给脚本执行权限

chmod a+x keepalived_check_mysql.sh

在配置文件中引用脚本

[root@master  keepalived]# cat keepalived.conf 
! Configuration File for keepalivedglobal_defs {router_id directory1 
}
vrrp_script check_run {script "/etc/keepalived/keepalived_check_mysql.sh"interval 5
}vrrp_instance VI_1 {state MASTERinterface ens33virtual_router_id 66priority 100advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {10.36.192.233/24}track_script {check_run}
}

[root@slave keepalived]# cat keepalived.conf 
! Configuration File for keepalivedglobal_defs {router_id directory2
}
vrrp_script check_run {script "/etc/keepalived/keepalived_check_mysql.sh"interval 5
}vrrp_instance VI_1 {state BACKUPnopreemptinterface ens33virtual_router_id 66priority 50advert_int 1authentication {auth_type PASSauth_pass 1111}virtual_ipaddress {10.36.192.233/24}track_script {#check_runcheck_run}
}

启动keepalived

systemctl start keepalived

在master端查看到虚拟IP

[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:99:b8:b4 brd ff:ff:ff:ff:ff:ffinet 10.36.192.223/24 brd 10.36.192.255 scope global noprefixroute dynamic ens33valid_lft 250228sec preferred_lft 250228secinet 10.36.192.233/24 scope global secondary ens33valid_lft forever preferred_lft forever

在测试机器测试

[root@mysql ~]# mysql -umalong -pQianfeng@123! -h10.36.192.233 
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 635
Server version: 5.7.42 MySQL Community Server (GPL)Copyright (c) 2000, 2023, Oracle and/or its affiliates.Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| dbtest             |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
5 rows in set (0.00 sec)

此时查看的是master端的数据库

停掉master端的msyql

[root@master ~]# systemctl stop mysqld[root@master ~]# systemctl status keepalived
● keepalived.service - LVS and VRRP High Availability MonitorLoaded: loaded (/usr/lib/systemd/system/keepalived.service; disabled; vendor preset: disabled)Active: inactive (dead)此时的虚拟ip在slave端
[root@slave ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:9f:83:60 brd ff:ff:ff:ff:ff:ffinet 10.36.192.222/24 brd 10.36.192.255 scope global noprefixroute dynamic ens33valid_lft 258272sec preferred_lft 258272secinet 10.36.192.233/24 scope global secondary ens33valid_lft forever preferred_lft forever

使用测试机子登录远程MySQL

[root@mysql ~]# mysql -umalong -pQianfeng@123! -h10.36.192.233 -P 3306
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
...
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.01 sec)

此时查看到的是slave机器的数据库

此时先启动master端的数据库，与keepalived，顺序不能乱

[root@master ~]# systemctl start mysqld
[root@master ~]# systemctl start keepalived查看此时的虚拟IP 在master端上
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:99:b8:b4 brd ff:ff:ff:ff:ff:ffinet 10.36.192.223/24 brd 10.36.192.255 scope global noprefixroute dynamic ens33valid_lft 257980sec preferred_lft 257980secinet 10.36.192.233/24 scope global secondary ens33valid_lft forever preferred_lft forever

测试机查看到数据库此时是master端的数据库

[root@mysql ~]# mysql -umalong -pQianfeng@123! -h10.36.192.233 -P 3306
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
...
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| dbtest             |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
5 rows in set (0.01 sec)

也就是当master，slave端的MySQL与keepalived同时开启时，虚拟IP会在master端，此时测试机远程登录的MySQL也是master端的

当master端的MySQL与keepalived停掉后，虚拟IP会飘向slave端，此时测试机远程登录的MySQL是slave端的。

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