CentOS7配置keepalived(1) 编译安装keepalived

该文档在CentOS7.6系统下进行编译安装keepalived 2.0.20

主机名称	ip地址	操作系统	角色	软件版本	备注
opsproxy-shqs-1	10.99.73.38 (real ip)	CentOS 7.6	keepalived	2.0.20
opsproxy-shqs-1	10.99.73.39 (real ip)	CentOS 7.6	keepalived	2.0.20
	10.99.73.40 (vip)		VIP

备注：
当前最新 版本应该是2.1.3, 在centos7下编译安装后，功能一切正常，就是就是日志配置不生效（还是生成在/var/log/messages下，rsyslog的配置不生效）。
同样的方式编译安装2.0.20以及1系列版本1.4.5日志的配置是生效的。

一、编译安装keepalived

1.1 下载keepalived源码包

wget https://www.keepalived.org/software/keepalived-2.0.20.tar.gz
tar zxvf keepalived-2.0.20.tar.gz

1.2 编译安装keepalived

我的编译软件统一安装在/opt/app/install/目录下面，然后软连接到/opt/app/下面。所以这里设置keepalived的安装目录为/opt/app/install/keepalived

# 准备编译环境
yum install -y ipvsadm popt popt-devel libnl libnl-devel libnl3-devel libnfnetlink libnfnetlink-devel net-snmp-devel openssl openssl-devel

# 切换到keepalived源码根目录
cd keepalived-2.0.20

# 编译
./configure --with-init=systemd --with-systemdsystemunitdir=/usr/lib/systemd/system --prefix=/opt/app/install/keepalived --with-run-dir=/opt/app/install/keepalived/run 

make

# 安装
make install

# 可执行文件拷贝一份到系统执行文件目录，该目录在path变量里面，可以直接使用keepalived命令
cp /opt/app/install/keepalived/sbin/keepalived /usr/sbin/keepalived   
# 或者
# ln -s /opt/app/install/keepalived/sbin/keepalived /usr/sbin/keepalived

# 软连接（这一步谨是我自己对软件目录管理的需求）
ln -s /opt/app/install/keepalived /opt/app/keepalived

# keepalived附加参数文件，为了跟yum安装一致，其实是不用配置的。启动文件指定实际路径就可以了。
ln -s /opt/app/install/keepalived/etc/sysconfig/keepalived /etc/sysconfig/keepalived


# pid文件放置目录,目录可以自己定义在启动脚本里面使用
mkdir /opt/app/install/keepalived/run

1.3 配置system自启动文件

根据上面的编译安装，实际已经生成了启动文件，我们这里进行一些修改。

• 编写配置文件

  vi /usr/lib/systemd/system/keepalived.service
  
  [Unit]
  Description=LVS and VRRP High Availability Monitor
  After=network-online.target syslog.target
  Wants=network-online.target
  
  [Service]
  Type=forking
  PIDFile=/run/keepalived.pid
  KillMode=process
  EnvironmentFile=-/etc/sysconfig/keepalived
  ExecStart=/usr/sbin/keepalived -f /opt/app/keepalived/etc/keepalived/keepalived.conf $KEEPALIVED_OPTIONS 
  ExecReload=/bin/kill -HUP $MAINPID
  
  [Install]
  WantedBy=multi-user.target
  

• 加载文件

  systemctl daemon-reload
  

以上，keepalived主备节点操作相同。

---

1.4 keepalived配置文件

这里仅仅是一个简单的配置文件,在haproxy服务中使用，部署验证这些就够了，更多参数配置需要了在补充吧。
配置文件目录/opt/app/keepalived/etc/keepalived/keepalived.conf

主备节点需要一致的参数:router_id ，virtual_router_id
主备节点优先级可以设置为主高备低：priority

• Master节点

  vi /opt/app/keepalived/etc/keepalived/keepalived.conf
  
  global_defs {
         
     router_id haproxy
  }
  vrrp_script chk_haproxy {
         
      script "/opt/app/keepalived/etc/keepalived/chk_haproxy.sh"
      interval 2
      weight 2
  }
  vrrp_instance VI_1 {
         
      state MASTER
      interface eth0
      virtual_router_id 55
      priority 101
      advert_int 1
      authentication {
         
          auth_type PASS
          auth_pass 1111
      }
      virtual_ipaddress {
         
          10.99.73.40
      }
      track_script {
         
          chk_haproxy
      }
  }
  

• backup节点

  vi /opt/app/keepalived/etc/keepalived/keepalived.conf
  
  global_defs {
         
     router_id haproxy
  }
  vrrp_script chk_haproxy {
         
      script "/opt/app/keepalived/etc/keepalived/chk_haproxy.sh"
      interval 2
      weight 2
  }
  vrrp_instance VI_1 {
         
      state BACKUP
      interface eth0
      virtual_router_id 55
      priority 100 
      advert_int 1
      authentication {
         
          auth_type PASS
          auth_pass 1111
      }
      virtual_ipaddress {
         
          10.99.73.40
      }
      track_script {
         
          chk_haproxy
      }
  }
  

  • 定义haproxy状态监控，如果haproxy没有运行，会监控到并主动拉起haproxy服务。

  vi /opt/app/keepalived/etc/keepalived/chk_haproxy.sh
  #!/bin/bash
  if [ $(ps -C haproxy --no-header | wc -l) -eq 0 ]; then
          systemctl start haproxy
  fi
  
  chmod +x /opt/app/keepalived/etc/keepalived/chk_haproxy.sh
  

• 配置自启动

  systemctl enable keepalived.service
  

• 启动服务

  systemctl start keepalived.service
  systemctl status keepalived.service
  

• 验证VIP的漂移

  #-----------------------------------
  # 1. 初次启动看下VIP
  #-----------------------------------
  # 主节点(master)
  # ip add
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
      link/ether fa:16:3e:5f:60:52 brd ff:ff:ff:ff:ff:ff
      inet 10.99.73.38/24 brd 10.99.73.255 scope global eth0
         valid_lft forever preferred_lft forever
      inet 10.99.73.40/32 scope global eth0                    #这里
         valid_lft forever preferred_lft forever
  # 备节点(backup)
  # ip add
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
      link/ether fa:16:3e:84:54:be brd ff:ff:ff:ff:ff:ff
      inet 10.99.73.39/24 brd 10.99.73.255 scope global eth0
         valid_lft forever preferred_lft forever
  
  #-----------------------------------
  # 2. 关闭主节点keepalived服务
  #-----------------------------------
  # 主节点(master)
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
      link/ether fa:16:3e:5f:60:52 brd ff:ff:ff:ff:ff:ff
      inet 10.99.73.38/24 brd 10.99.73.255 scope global eth0        #可以看到VIP已经漂走了
         valid_lft forever preferred_lft forever
  # 备节点(backup)
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
      link/ether fa:16:3e:84:54:be brd ff:ff:ff:ff:ff:ff
      inet 10.99.73.39/24 brd 10.99.73.255 scope global eth0
         valid_lft forever preferred_lft forever
      inet 10.99.73.40/32 scope global eth0                     #可以看到VIP已经漂过来了，很快很快
         valid_lft forever preferred_lft forever
  
  #-----------------------------------
  # 3. 重新开启主节点keepalived服务，因为我们配置的主节点优先级比较高，虽然备节点正常，但VIP还是会漂过来的。
  #-----------------------------------
  # 主节点(master)
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
      link/ether fa:16:3e:5f:60:52 brd ff:ff:ff:ff:ff:ff
      inet 10.99.73.38/24 brd 10.99.73.255 scope global eth0
         valid_lft forever preferred_lft forever
      inet 10.99.73.40/32 scope global eth0
  # 备节点(backup)
  2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
      link/ether fa:16:3e:84:54:be brd ff:ff:ff:ff:ff:ff
      inet 10.99.73.39/24 brd 10.99.73.255 scope global eth0
         valid_lft forever preferred_lft forever
  

• 验证监控脚本会自动拉起haproxy

  # 查看当前haproxy状态，确认启动时间以及PID
  systemctl status haproxy|grep -A 1 Active
     Active: active (running) since Fri 2020-07-03 16:11:25 CST; 4min 27s ago
   Main PID: 3942 (haproxy)
  
  # 执行关闭haproxy，查看是否被自动拉起服务
  systemctl stop haproxy
  systemctl status haproxy|grep -A 1 Active
     Active: active (running) since Fri 2020-07-03 16:16:47 CST; 601ms ago
   Main PID: 8382 (haproxy)
  

  可以看到haproxy被keepalived自动拉起来了，验证完成。

1.5 日志配置

• 编辑启动环境变量文件，将日志配置到local[0-7]中的一个，这里配置到local1 （因为我已经将haproxy的日志配置到local0）

vi /opt/app/install/keepalived/etc/sysconfig/keepalived
# Options for keepalived. See `keepalived --help' output and keepalived(8) and
# keepalived.conf(5) man pages for a list of all options. Here are the most
# common ones :
#
# --vrrp               -P    Only run with VRRP subsystem.
# --check              -C    Only run with Health-checker subsystem.
# --dont-release-vrrp  -V    Dont remove VRRP VIPs & VROUTEs on daemon stop.
# --dont-release-ipvs  -I    Dont remove IPVS topology on daemon stop.
# --dump-conf          -d    Dump the configuration data.
# --log-detail         -D    Detailed log messages.
# --log-facility       -S    0-7 Set local syslog facility (default=LOG_DAEMON)
#

KEEPALIVED_OPTIONS="-D -d -S 1"

• 配置rsyslog

vi /etc/rsyslog.d/keepalived.conf
$ModLoad imudp
$UDPServerRun 514
local1.* /var/log/keepalived.log

• 重启rsyslog，然后重启keepalived

systemctl restart rsyslog
systemctl restart keepalived

systemctl status keepalived
● keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; enabled; vendor preset: disabled)
   Active: active (running) since Sun 2020-07-05 00:55:27 CST; 427ms ago
  Process: 32314 ExecStart=/usr/sbin/keepalived -f /opt/app/keepalived/etc/keepalived/keepalived.conf $KEEPALIVED_OPTIONS (code=exited, status=0/SUCCESS)
 Main PID: 32315 (keepalived)
    Tasks: 2
   Memory: 704.0K
   CGroup: /system.slice/keepalived.service
           ├─32315 /usr/sbin/keepalived -f /opt/app/keepalived/etc/keepalived/keepalived.conf -D -d -S 1
           └─32316 /usr/sbin/keepalived -f /opt/app/keepalived/etc/keepalived/keepalived.conf -D -d -S 1

可以看到配置已经生效了。

tail -f  /var/log/keepalived.log
...<省略>