一、环境介绍：
1.1服务器角色配置：
mysql-master 10.0.0.101(外) 172.168.1.101(内)
mysql-slave 10.0.0.103 (外) 172.168.1.103(内)
mysql-router01 10.0.0.102 (外) 172.168.1.102(内)
mysql-router02 10.0.0.104 (外) 172.168.1.104(内)
jumpserver 10.0.0.128 (外) 172.168.1.128(内)1.2配置数据库的一主两从库
Slave01 和master都是允许读写的，slave02提供只读
同时MySQL的主从复制都是事先配置成功的(此环境是开启GTID模式的复制)
1.3部署web应用jumpserver
jumpserver web 10.0.0.128(外) 172.168.1.128（内）
jumpsever配置文件如下：
[root@localhost jumpserver]# cat /opt/jumpserver/jumpserver.conf
[base]
url = http://10.0.0.128
key = f1tty6elu8h03x2k
ip = 0.0.0.0 ###默认监听任何IP
port = 8000 ###为jumpsever的默认的web端口
log = debug
[db]
engine = mysql
host = 172.168.1.20 ####为虚拟VIP
port = 7001 ####为mysqlroute读写模式的默认端口
####jumpserver的连接数据库的地址
user = jumpserver
password = jumpserver
database = jumpserver
[mail]
mail_enable = 1
email_host = [email protected]
email_port = 25
email_host_user = [email protected]
email_host_password = weuidnre
email_use_tls = False
email_use_ssl = False
[connect]
nav_sort_by = ip启动jumpsever服务：
[root@localhost jumpserver]# /opt/jumpserver/service.sh stop
[root@localhost jumpserver]# /opt/jumpserver/service.sh start
[root@localhost jumpserver]# /opt/jumpserver/service.sh status
jumpserver is running... [ OK ]
[root@localhost jumpserver]#
[root@localhost jumpserver]# ps -ef|grep python
root 2443 2441 0 May14 ? 00:00:00 /bin/bash -c ulimit -S -c 0 >/dev/null 2>&1 ; python ./run_server.py
root 2444 2443 0 May14 ? 00:00:04 python ./run_server.py
root 9081 8974 0 14:50 pts/0 00:00:00 grep python1.4安装keepalived和mysql-router
mysql-router01 10.0.0.102 mysql-router02 10.0.0.104
在10.0.0.102 机器上安装keepalived 和mysql-router
在10.0.0.104 机器上安装keepalived 和mysql-router
[root@master01 ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
slave01 172.168.1.103
master01 172.168.1.101
router01 172.168.1.102
router02 172.168.1.104
slave02 172.168.1.105重要提示：
为快速实现环境达到演示效果，建议6台台虚拟机先关闭selinux和iptables，保证服务器的系统时间都是一致的，必须保证iptables不是开机自启动，安装keepalived和mysql-router后，要保证这2个服务是开启自启动的。
二、keepalived相关原理介绍：
Keepalived 是一种高性能的服务器高可用或热备解决方案，Keepalived可以用来防止服务器单点故障(单点故障是指一旦某一点出现故障就会导致整个系统架构的不可用)的发生，通过配合Nginx可以实现web前端服务的高可用。以下本文会介绍keepalived结合mysql-router实现数据库得高可用
Keepalived实现的基础是VRRP协议，Keepalived就是巧用VRRP协议来实现高可用性(HA)的.
VRRP(Virtual Router Redundancy Protocol)协议是用于实现路由器冗余的协议，VRRP协议将两台或多台路由器设备虚拟成一个设备，对外提供虚拟路由器IP(一个或多个)，而在路由器组内部，如果实际拥有这个对外IP的路由器如果工作正常的话就是MASTER，或者是通过算法选举产生，MASTER实现针对虚拟路由器IP的各种网络功能，如ARP请求，ICMP，以及数据的转发等；其他设备不拥有该IP，状态是BACKUP，除了接收MASTER的VRRP状态通告信息外，不执行对外的网络功能。当主机失效时，BACKUP将接管原先MASTER的网络功能。
VRRP协议使用多播数据来传输VRRP数据，VRRP数据使用特殊的虚拟源MAC地址发送数据而不是自身网卡的MAC地址，VRRP运行时只有MASTER路由器定时发送VRRP通告信息，表示MASTER工作正常以及虚拟路由器IP(组)，BACKUP只接收VRRP数据，不发送数据，如果一定时间内没有接收到MASTER的通告信息，各BACKUP将宣告自己成为MASTER，发送通告信息，重新进行MASTER选举状态。
三．Mysql-router相关原理介绍：
3.1.什么是mysql route
MySQL Router是处于应用client和dbserver之间的轻量级代理程序，它能检测，分析和转发查询到后端数据库实例，并把结果返回给client。是mysql-proxy的一个替代品。其架构图和功能如下：
（1）Router实现读写分离，程序不是直接连接数据库IP，而是固定连接到mysql router。MySQL Router对前端应用是透明的。应用程序把MySQL Router当作是普通的mysql实例，把查询发给MySQL Router,而MySQL Router会把查询结果返回给前端的应用程序。
（2）从数据库服务器故障，业务可以正常运行。由MySQL Router来进行自动下线不可用服务器。程序配置不需要任何修改。
（3）主数据库故障，由MySQL Router来决定主从自动切换，业务可以正常访问。程序配置不需要做任何修改。
3.2.读写分离原理
MySQL Router接受前端应用程序请求后，根据不同的端口来区分读写，把连接读写端口的所有查询发往主库，把连接只读端口的select查询以轮询方式发往多个从库，从而实现读写分离的目的。读写返回的结果会交给MySQL Router,由MySQL Router返回给客户端的应用程序。
3.3.Mysql router用途
MySQL Router的主要用途是读写分离，主主故障自动切换，负载均衡，连接池等。
3.4.Mysql router主主故障自动切换的坑
Mysql router主主故障切换功能经过测试没有问题，但是有一个比较大的坑需要注意
Mysql router的主主故障切换如果是运行在一主一从的情况下，从库作为主库的备份，这种情况是使用mysql router主主故障切换是没有问题的，但是在一主多从的情况下使用主主故障切换就会处在如下问题：mysql主库挂掉了，从库slave01和slave02却一直是同步的原来的主库master的IP地址，导致slave上的IO线程一直是connecting状态,导致slave02复制失败。
四．软件具体安装部署
10.0.0.102机器上安装mysql-router 和keepalived
此机器上的keepalived是主
yum -y install openssl-devel
wget http://www.keepalived.org/software/keepalived-1.4.0.tar.gz
tar xf keepalived-1.4.0.tar.gz -C /usr/local/
cd /usr/local/keepalived-1.4.0/
./configure
make
make install
mkdir /etc/keepalived
find /usr/local/keepalived-1.4.0/ -name "keepalived.conf"
cp /usr/local/keepalived-1.4.0/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
find / -name "keepalived"
cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
cp /usr/local/keepalived-1.4.0/keepalived/etc/init.d/keepalived /etc/init.d/
chmod +x /etc/init.d/keepalived
chkconfig keepalived on
cp /usr/local/sbin/keepalived /usr/sbin/
which keepalived
cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.ori下面的配置文件是master主keepalived的配置文件
vim /etc/keepalived/keepalived.conf
[root@master01 ~]# cat /etc/keepalived/keepalived.conf
global_defs {
notification_email {
[email protected]
}
notification_email_from [email protected]
smtp_server 192.168.200.1
smtp_connect_timeout 30
**router_id LVS_01**
}
vrrp_instance VI_1 {
** state MASTER**
**interface eth1**
virtual_router_id 51
**priority 120**
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
**172.168.1.20/24**
}
}
/etc/init.d/keepalived status
/etc/init.d/keepalived start同样的方式在10.0.0.104机器上安装mysql-router 和keepalived
此机器上的keepalived是从
下面是从keepalived机器的配置文件介绍：
[root@router02 ~]# cat /etc/keepalived/keepalived.conf
global_defs {
notification_email {
[email protected]
}
notification_email_from [email protected]
smtp_server 192.168.200.1
smtp_connect_timeout 30
** router_id LVS_02**
}
vrrp_instance VI_1 {
** state BACKUP
interface eth1**
virtual_router_id 51
** priority 80**
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
** 172.168.1.20/24**
}
}主从keepalived参数介绍：
先是主keepalived服务器：
global_defs
{
notification_email #通知email，根据实际情况配置
{
[email protected]
}
notification_email_from [email protected]
smtp_server 127.0.0.1
stmp_connect_timeout 30
router_id node1 #节点名标识，主要用于通知中
}
vrrp_instance VI_NODE {
state MASTER #配置为主服务器
interface eth0 #通讯网卡
virtual_router_id 100 #路由标识
priority 200 #优先级，0-254
advert_int 5 #通知间隔，实际部署时可以设置小一点，减少延时
authentication {
auth_type PASS
auth_pass 123456 #验证密码，用于通讯主机间验证
}
virtual_ipaddress {
192.168.1.206 #虚拟ip，可以定义多个
}
}接下是从服务器设置：
global_defs {
notification_email {
[email protected]
}
notification_email_from [email protected]
smtp_server 127.0.0.1
stmp_connect_timeout 30
router_id node2
}
vrrp_instance VI_NODE {
state BACKUP #与主服务器对应
interface eth0 #从服务器的通信网卡
virtual_router_id 100 #路由标识，和主服务器相同
priority 100 #优先级，小于主服务器即可
advert_int 5 #这里是接受通知间隔，与主服务器要设置相同
authentication {
auth_type PASS
auth_pass 123456 #验证密码，与主服务器相同
}
virtual_ipaddress {
192.168.1.206 #虚拟IP，也要和主服务器相同
}
}上面的设置是最基础的设置，实现的功能是如果主服务器的Keepalived停止服务（一般情况下服务器宕机），则将虚拟IP切换至从服务器，主服务器恢复后从新切换回主服务器。
4.1、Keepalived的配置文件介绍来实现虚拟VIP漂移
注意：1、两个keepalived.conf配置文件中添加的虚拟网卡要一样，并且不要和已使用服务器的内外网卡一样这样就实现不了心跳了。
可以是同一网段局域内网卡，也可以是同一网段外网网卡
2、当主keepalived应用开启的时候，是可以看到虚拟IP地址的
[root@router01 ~]# ps -ef|grep keepalived
root 9265 1 0 07:24 ? 00:00:00 keepalived -D
root 9267 9265 0 07:24 ? 00:00:00 keepalived -D
root 9268 9265 0 07:24 ? 00:00:05 keepalived -D
root 9517 9492 0 10:02 pts/3 00:00:00 grep keepalived
[root@router01 ~]# ip addr|grep 172.168.1.20
inet 172.168.1.20/24 scope global secondary eth1这时从keepalived程序也开启，但是在从本地是grep不到虚拟IP地址的
[root@router02 ~]# ps -ef|grep keepalived
root 13115 1 0 07:08 ? 00:00:00 keepalived -D
root 13117 13115 0 07:08 ? 00:00:00 keepalived -D
root 13118 13115 0 07:08 ? 00:00:01 keepalived -D
root 13271 13232 0 10:02 pts/2 00:00:00 grep keepalived
[root@router02 ~]# ip a|grep 172.168.1.20
[root@router02 ~]#一旦主keepalived程序关闭或者是服务器挂掉，这时虚拟VIP就可以实现跳跃到从keepalived机器上。
[root@router01 ~]# /etc/init.d/keepalived stop
Stopping keepalived: [ OK ]
[root@router01 ~]# ps -ef|grep keepalived
root 9540 9492 0 10:21 pts/3 00:00:00 grep keepalived
[root@router01 ~]#
[root@router02 ~]# ip a|grep 172.168.1.20
inet 172.168.1.20/24 scope global secondary eth1
[root@router02 ~]#提示：
如果从负载均衡服务器grep不到虚拟网卡原因有：
1、本地服务器keepalived程序可能关闭，得restart从启才行，才能实现虚拟网卡的跳跃。
2、就是主负载均衡服务器keepalived程序没有关闭而导致
3、主负载均衡服务器只要keepalived服务启动就不会出现上述的问题。
4.服务器的iptables没关闭导致，或者是selinxu没关闭也有可能导致
4.2．安装mysql-router
10.0.0.102 10.0.0.104两个机器安装mysql-router
采用二进制安装mysql-router：
tar xf mysql-router-2.1.6-linux-glibc2.12-x86-64bit.tar.gz -C /usr/local/
cd /usr/local/
ln -s mysql-router-2.1.6-linux-glibc2.12-x86-64bit mysql-router
mkdir /etc/mysql-route/
mkdir /data/log/mysql-route -p
cp /usr/local/mysql-router/share/doc/mysqlrouter/sample_mysqlrouter.conf /etc/mysql-route/mysqlrouter.conf
cp /etc/mysql-route/mysqlrouter.conf /etc/mysql-route/mysqlrouter.conf.ori4.3配置文件介绍如下：
[root@router01 mysql-route]# cat mysqlrouter.conf
[DEFAULT]
##日志存放目录
logging_folder = /data/log/mysql-route
##插件存放目录
plugin_folder = /usr/local/mysql-router/lib/mysqlrouter
###配置文件存放目录
config_folder = /etc/mysql-route
###运行目录
runtime_folder = /var/run
[logger]
###日志运行级别
level = INFO
#[fabric_cache]
#address = your_fabric_node.example.com:32275
#user =
###主节点故障转移
[routing:basic_failover]
#To be more transparent, use MySQL Server port 3306
##写节点地址
bind_address=172.168.1.20 ##{此IP地址为虚拟VIP}
##写节点端口
bind_port = 7001
##主库为读写模式
mode = read-write
###172.168.1.101为mysql 主 172.168.1.103为mysql从
#### 主节点地址：默认情况下第一台主数据库为写主库，当第一台主数据库DOWN机后，第二台数据库被提升为主库
destinations = 172.168.1.101:3306,172.168.1.103:3306
[routing:balancing]
bind_address=172.168.1.20
bind_port = 7002
connect_timeout = 3
max_connections = 1024
###为mysql从库（此处只负责读）
destinations = 172.168.1.105:3306
mode = read-only
#[routing:homepage_reads_fabric]
#bind_port = 7002
#destinations = fabric+cache:///group/homepage_group?allow_primary_reads=yes
#mode = read-only
#If no plugin is configured which starts a service, keepalive
#will make sure MySQL Router will not immediately exit. It is
#safe to remove once Router is configured.
[keepalive]
interval = 60启动mysqlrouter服务
/usr/local/mysql-router/bin/mysqlrouter -c /etc/mysql-route/mysqlrouter.conf &
关闭iptables 保证mysql-router开机自启动
[root@router01 ~]# chkconfig --list|grep iptables
iptables 0:off 1:off 2:off 3:off 4:off 5:off 6:off
[root@router01 ~]# chkconfig iptables off
[root@router01~]# vim /etc/rc.local
#!/bin/sh
touch /var/lock/subsys/local
/usr/local/mysql-router/bin/mysqlrouter -c /etc/mysql-route/mysqlrouter.conf &
[root@router02 ~]# chkconfig --list|grep iptables
iptables 0:off 1:off 2:off 3:off 4:off 5:off 6:off
[root@router02 ~]# chkconfig iptables off
[root@router02 ~]# vim /etc/rc.local
#!/bin/sh
touch /var/lock/subsys/local
/usr/local/mysql-router/bin/mysqlrouter -c /etc/mysql-route/mysqlrouter.conf &4.4创建测试账户进行测试：
登录mysql master主库进行创建后，账户会同步到各个slave上
mysql> grant all on jumpserver.* to jumpserver@'172.168.1.%' identified by 'jumpserver';
[root@master01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |
[root@router01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |
[root@slave01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |4.4.1第一台主库DOWN后，MySQL Router如何处理？
当第一台主数据库DOWN机后，第二台slave备份数据库被提升为主库，所以此时查看到的主机名字变为了slave01
[root@master01 ~]# /etc/init.d/mysql stop
Shutting down MySQL.............. SUCCESS!
[root@master01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+---------+
| Variable_name | Value |
+---------------+---------+
| hostname | slave01 |
+---------------+---------+
[root@master01 ~]#
[root@router02 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+---------+
| Variable_name | Value |
+---------------+---------+
| hostname | slave01 |
+---------------+---------+
[root@router02 ~]#
[root@router01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
+---------------+---------+
| Variable_name | Value |
+---------------+---------+
| hostname | slave01 |
+---------------+---------+
[root@router01 ~]#4.4.2.稍后如果第一台主库被修复重启后，连接的数据库又会是那个呢？
如果第一台主库被修复重启后，那么默认仍然连接第二台为主库进行读写，不会自动切回到第一台主库。
重新启动主库master测试：
[root@master01 ~]# /etc/init.d/mysql start
Starting MySQL.................... SUCCESS!
[root@master01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+---------+
| Variable_name | Value |
+---------------+---------+
| hostname | slave01 |
+---------------+---------+4.4.3.如果第一台主数据库被修复后，又希望切换回第一台主库，怎么办？
可以重启MySQL Router 此时需要把router01和router02机器上的mysql-router服务都重新启动下，才可以切换回原来的主库
[root@router01 ~]# kill -9 9598
[root@router01 ~]# /usr/local/mysql-router/bin/mysqlrouter -c /etc/mysql-route/mysqlrouter.conf &
[1] 9791
[root@router02 ~]# kill -9 13571
[1]+ Killed /usr/local/mysql-router/bin/mysqlrouter -c /etc/mysql-route/mysqlrouter.conf
[root@router02 ~]# /usr/local/mysql-router/bin/mysqlrouter -c /etc/mysql-route/mysqlrouter.conf &
[1] 13627
[root@router02 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |
+---------------+----------+
[root@router02 ~]#
[root@router01 ~]#
[root@router01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |
+---------------+----------+五、通过jumpserver的web页面程序演示
5.1首先是安装完成jumpserver后要能够正常的登录
5.2关闭10.0.0.102keepalive主机器router01测试高可用
VIP172.168.1.20飘到10.0.0.104机器上
[root@router02 ~]# ip a|grep 172.168.1.20
inet 172.168.1.20/24 scope global secondary eth1
[root@router02 ~]#
root@router02 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
mysql: [Warning] Using a password on the command line interface can be insecure.
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |
+---------------+----------+此时访问jumpserver web看是否可以正常登录？
经测试是没问题的，jumpserver web可以正常打开的
重启10.0.0.102机器mysql-router01
VIP再次又票到10.0.0.102 机器上
[root@router01 ~]# ip a|grep 172.168.1.20
inet 172.168.1.20/24 scope global secondary eth1
[root@router01 ~]# mysql -h172.168.1.20 -P7001 -ujumpserver -pjumpserver -e "show variables like 'hostname';"
+---------------+----------+
| Variable_name | Value |
+---------------+----------+
| hostname | master01 |
+---------------+----------+
[root@router01 ~]#Jumpserver web依然可以继续打开
到此处，基于mysql的一主多从的高可用演示完毕，当然此方案和MHA相比，还没完全做到MHA的智能高可用