MyCat HA Keepalived搭建热备架构 | Eddie'Blog
MyCat HA Keepalived搭建热备架构

MyCat HA Keepalived搭建热备架构

eddie 494 2020-11-10

目录

前言

假如Haproxy崩溃了,自然也是没有用的。所以引入 Keepalived 搭建热备架构

一、前提条件

MyCat Haproxy实践》在此文章中,已经编写了安装HA的流程。所以在 192.168.8.245 服务器上再次安装一遍 HA

序号地址用途
1192.168.8.245:5000Haproxy-B
2192.168.8.247:5000Haproxy-A
3192.168.8.249:6000Keepalived-VIP

二、修改第二台HA的配置文件

[root@localhost ~]# vim /etc/haproxy/haproxy.cfg      
      
#---------------------------------------------------------------------
# Example configuration for a possible web application.  See the
# full configuration options online.
#
#   http://haproxy.1wt.eu/download/1.4/doc/configuration.txt
#
#---------------------------------------------------------------------

#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
    # to have these messages end up in /var/log/haproxy.log you will
    # need to:
    #
    # 1) configure syslog to accept network log events.  This is done
    #    by adding the '-r' option to the SYSLOGD_OPTIONS in
    #    /etc/sysconfig/syslog
    #
    # 2) configure local2 events to go to the /var/log/haproxy.log
    #   file. A line like the following can be added to
    #   /etc/sysconfig/syslog
    #
    #    local2.*                       /var/log/haproxy.log
    #
    log         127.0.0.1 local2

    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon

    # turn on stats unix socket
    stats socket /var/lib/haproxy/stats

#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
    mode                    tcp               #### http change tcp
    log                     global
    option                  tcplog            #### httplog change tcplog
    option                  dontlognull
    #option http-server-close                 #### 屏蔽此行
    #option forwardfor       except 127.0.0.0/8    #### 屏蔽此行
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000

#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend  main *:5000
    #acl url_static       path_beg       -i /static /images /javascript /stylesheets       #### 屏蔽此行
    #acl url_static       path_end       -i .jpg .gif .png .css .js       #### 屏蔽此行

    #use_backend static          if url_static     #### 屏蔽此行
    default_backend             app

#---------------------------------------------------------------------
# static backend for serving up images, stylesheets and such
#---------------------------------------------------------------------
backend static
    balance     roundrobin
    server      static 127.0.0.1:4331 check

#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend app
    balance     roundrobin
    server  app1 192.168.8.245:8066 check   #### server  app1 127.0.0.1:5001 check
    server  app2 182.168.8.246:8066 check   #### server  app2 127.0.0.1:5002 check   
    #server  app3 127.0.0.1:5003 check  #### 屏蔽此行
    #server  app4 127.0.0.1:5004 check  #### 屏蔽此行

2.1 检查与运行

[root@localhost ~]# haproxy -f /etc/haproxy/haproxy.cfg 
[root@localhost ~]# ps -ef | grep hapro                  
haproxy   5868     1  0 14:31 ?        00:00:00 haproxy -f /etc/haproxy/haproxy.cfg
root      5897 28651  0 14:31 pts/0    00:00:00 grep --color=auto hapro

2.2 工具连接

使用 Navicat 连接

三、8.245 安装 Keepalived

yum search keepalived
yum -y install keepalived.x86_64

3.1 修改 8.245 配置

[root@localhost ~]# vim /etc/keepalived/keepalived.conf    

! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   #vrrp_strict    #### 屏蔽此行,会影响到使用虚拟IP
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state MASTER
    interface enp0s3       #### eth0 配置网卡 ip addr
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.8.249     #### 修改成 虚拟IP地址 需要和服务器同网段
    }
}

virtual_server 192.168.8.249 6000 {    ####  虚拟IP地址 和 监听的端口
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.8.245 5000 {   #### HA的地址 和 端口
        weight 1

        #### 下面是心跳检查
        ####  https://keepalived.org/doc/configuration_synopsis.html

        TCP_CHECK {                 #### 使用TCP的心跳检测
            connect_port 5000       #### 监听端口
            connect_timeout 10      #### 心跳超时时间
        }

    }
}

3.2 在 8.247 安装 Keepalived

[root@storage ~]# yum -y install keepalived.x86_64

[root@storage ~]# cd /etc/keepalived/ 
[root@storage keepalived]# ls
keepalived.conf
[root@storage keepalived]# rm -rf keepalived.conf*
[root@storage keepalived]# ls -la
total 12
drwxr-xr-x   2 root root    6 Nov 10 15:05 .
drwxr-xr-x. 85 root root 8192 Nov 10 15:03 ..

[root@storage keepalived]# scp root@192.168.8.245:/etc/keepalived/keepalived.conf .
The authenticity of host '192.168.8.245 (192.168.8.245)' can't be established.
ECDSA key fingerprint is SHA256:VQlowsizcHfSGLTyiPhQ6SQejAzAoKZ+MxOLDwkCh20.
ECDSA key fingerprint is MD5:3e:82:cc:d4:fa:00:96:a3:d8:80:e4:94:e3:26:58:2e.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.8.245' (ECDSA) to the list of known hosts.
root@192.168.8.245's password: 
keepalived.conf                                                                           100% 1347     1.6MB/s   00:00  

3.3 修改 8.247 Keepalived 的配置

[root@storage keepalived]# vim /etc/keepalived/keepalived.conf 
! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   #vrrp_strict    #### 屏蔽此行,会影响到使用虚拟IP
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state BACKUP           #### MASTER change BACKUP
    interface enp0s3       #### eth0 配置网卡 ip addr
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.8.249     #### 修改成 虚拟IP地址 需要和服务器同网段
    }
}

virtual_server 192.168.8.249 6000 {    ####  虚拟IP地址 和 监听的端口
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.8.247 5000 {   #### HA的地址 和 端口
        weight 1

        #### 下面是心跳检查
        ####  https://keepalived.org/doc/configuration_synopsis.html

        TCP_CHECK {                 #### 使用TCP的心跳检测
            connect_port 5000       #### 监听端口
            connect_timeout 10      #### 心跳超时时间
        }

    }
}

3.4 启动两台服务器 keepalived

[root@localhost ~]# keepalived -f /etc/keepalived/keepalived.conf 
[root@localhost ~]# ps -ef | grep keepalived                      
root     21020     1  0 15:14 ?        00:00:00 keepalived -f /etc/keepalived/keepalived.conf
root     21021 21020  0 15:14 ?        00:00:00 keepalived -f /etc/keepalived/keepalived.conf
root     21022 21020  0 15:14 ?        00:00:00 keepalived -f /etc/keepalived/keepalived.conf
root     21049 28651  0 15:14 pts/0    00:00:00 grep --color=auto keepalived

3.5 使用 keepalived 虚拟IP连接

图片.png

3.6 演示抢占VIP

对象:8.245

[root@localhost ~]# ps -ef | grep keepalived   # 查看进程
root      1774 28651  0 08:51 pts/0    00:00:00 grep --color=auto keepalived
root     21020     1  0 Nov10 ?        00:00:04 keepalived -f /etc/keepalived/keepalived.conf
root     21021 21020  0 Nov10 ?        00:00:07 keepalived -f /etc/keepalived/keepalived.conf
root     21022 21020  0 Nov10 ?        00:00:14 keepalived -f /etc/keepalived/keepalived.conf

[root@localhost ~]# kill 21020 21021 21022   # 杀死进程

[root@localhost ~]# ps -ef | grep keepalived   # 查看keepalived是否存在
root      1837 28651  0 08:52 pts/0    00:00:00 grep --color=auto keepalived

[root@localhost ~]# ip add | grep 192.168.8  # 查看VIP是否存在
    inet 192.168.8.245/24 brd 192.168.8.255 scope global noprefixroute enp0s3

对象:8.247

[root@storage keepalived]# ip add | grep 192.168.8
    inet 192.168.8.247/24 brd 192.168.8.255 scope global noprefixroute enp0s3
    inet 192.168.8.249/32 scope global enp0s3

最后运行回 8.245 keepalived

[root@localhost ~]# keepalived -f /etc/keepalived/keepalived.conf
 
[root@localhost ~]# ip add | grep 192.168.8
    inet 192.168.8.245/24 brd 192.168.8.255 scope global noprefixroute enp0s3

备注:当 8.245 的keepalived kill掉情况下, 虚拟IP 8.249 就会自动在 8.247 上出现,尽管 8.245 的keepalived 重新运行,虚拟IP 8.249 依然在 8.247上的服务器。

四、keepalived延伸HA宏机处理情况

4.1 安装 killall 检测插件

yum search killall
yum -y install psmisc.x86_64

8.245 和 8.247 都需要安装

4.2 使用 killall 检测 haproxy

对象 8.245

[root@localhost ~]# vim /etc/keepalived/keepalived.conf    

! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   #vrrp_strict    #### 屏蔽此行,会影响到使用虚拟IP
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_script chk_haproxy {
    script "killall -0 haproxy"  #### 检测 haproxy 是否运行
    interval 2   #### 两秒检测一次
}

vrrp_instance VI_1 {
    state MASTER
    interface enp0s3       #### eth0 配置网卡 ip addr
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.8.249     #### 修改成 虚拟IP地址 需要和服务器同网段
    }
    track_script {
        chk_haproxy  #### 添加检测 haproxy 方法
    }
}

virtual_server 192.168.8.249 6000 {    ####  虚拟IP地址 和 监听的端口
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.8.245 5000 {   #### HA的地址 和 端口
        weight 1
    }
}

--------
[root@localhost ~]# killall -0 haproxy    #### 没有任何提示就是存在,没有则提示"haproxy: no process found"

[root@localhost ~]# echo $?               #### 返回 0 就是存在,若返回 1 可以自行运行 haproxy -f /etc/haproxy/haproxy.cfg 
0

[root@localhost ~]# ps -ef | grep haproxy #### 查看 haproxy 进程是否存在
haproxy  19218     1  0 09:41 ?        00:00:00 haproxy -f /etc/haproxy/haproxy.cfg
root     19514 13983  0 09:42 pts/0    00:00:00 grep --color=auto haproxy

对象 8.247

[root@storage ~]# vim /etc/keepalived/keepalived.conf 

! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   #vrrp_strict    #### 屏蔽此行,会影响到使用虚拟IP
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}


vrrp_script chk_haproxy {
    script "killall -0 haproxy"  #### 检测 haproxy 是否运行
    interval 2   #### 两秒检测一次
}

vrrp_instance VI_1 {
    state BACKUP           #### MASTER change BACKUP
    interface enp0s3       #### eth0 配置网卡 ip addr
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.8.249     #### 修改成 虚拟IP地址 需要和服务器同网段
    }
    track_script {
        chk_haproxy  #### 添加检测 haproxy 方法
    }
}

virtual_server 192.168.8.249 6000 {    ####  虚拟IP地址 和 监听的端口
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.8.247 5000 {   #### HA的地址 和 端口
        weight 1
    }
}

启动流程:

(1)  8.245 和 8.247 都运行 “systemctl stop keepalived.service” 

[root@storage ~]# ps -ef | grep keepalived           
root      1156     1  0 Nov10 ?        00:00:05 keepalived -f /etc/keepalived/keepalived.conf
root      1157  1156  0 Nov10 ?        00:00:08 keepalived -f /etc/keepalived/keepalived.conf
root      1158  1156  0 Nov10 ?        00:00:18 keepalived -f /etc/keepalived/keepalived.conf
root      2634  2521  0 10:03 pts/0    00:00:00 grep --color=auto keepalived

出现这种不行的,如果 stop不行就直接 kill
[root@storage ~]# kill -9 1156 1157 1158 2634

-----------

(2) 8.245 和 8.247 都启动 keepalived  “systemctl start keepalived.service” 

[root@localhost ~]# ps -ef | grep keepalived           
root     26742     1  0 10:02 ?        00:00:00 /usr/sbin/keepalived -D
root     26743 26742  0 10:02 ?        00:00:00 /usr/sbin/keepalived -D
root     26744 26742  0 10:02 ?        00:00:00 /usr/sbin/keepalived -D
root     26747 13983  0 10:02 pts/0    00:00:00 grep --color=auto keepalived

因keepalived操作频繁,出现两台服务器出现8.249这个虚拟IP,Navicat是连接不到的,需要两台服务器都运行 “service network restart” 解决

测试流程:

  1. 前提条件,两台服务器都运行了 keepalived 和 haproxy
  2. 查看虚拟IP在8.247服务器,然后就在此服务器杀死 haproxy 进程,在查看ip addr,虚拟IP不见了
  3. 虚拟IP就迁移到 8.245服务器上

备注:必需有 haproxy 服务运行,不然 keepalived 脚本检测不到,就不会抢虚拟IP

五、命令汇总

systemctl stop keepalived.service
systemctl start keepalived.service
systemctl status keepalived.service
systemctl restart keepalived.service

keepalived -f /etc/keepalived/keepalived.conf
haproxy -f /etc/haproxy/haproxy.cfg  

service network restart

ps -ef | grep haproxy
ps -ef | grep keepalived

参考资料

https://keepalived.org/doc/configuration_synopsis.html

https://www.cnblogs.com/ilurker/p/6464103.html