1. 安装工具和依赖包

    yum install -y curl gcc openssl-devel libnl3-devel net-snmp-devel

  2. yum安装keepalived

    yum install -y keepalived

  3. 源码包安装keepalived

    [root@master src]# pwd
/usr/local/src
[root@master src]# wget https://www.keepalived.org/software/keepalived-2.2.7.tar.gz
[root@master src]# tar xvf keepalived-2.2.7.tar.gz
[root@master src]# cd keepalived-2.2.7
[root@master keepalived-2.2.7]# ./configure --prefix=/usr/local/keepalived
[root@master keepalived-2.2.7]# make && make install

  4. 安装后配置

    • 环境变量文件: /usr/local/etc/sysconfig/keepalived --修改KEEPALIVED_OPTIONS="-f /etc/keepalived/keepalived.conf -D"

    • 执行文件: /usr/local/sbin/keepalived

    • 配置文件: /usr/local/etc/keepalived/ --mv /usr/local/etc/keepalived/keepalived.conf.sample /usr/local/etc/keepalived/keepalived.conf

    keepalived --help
Usage: keepalived [OPTION...]
  -f, --use-file=FILE          Use the specified configuration file
                                default '/usr/local/etc/keepalived/keepalived.conf'
                                     or '/etc/keepalived/keepalived.conf'
  -P, --vrrp                   Only run with VRRP subsystem
  -C, --check                  Only run with Health-checker subsystem
      --all                    Force all child processes to run, even if have no configuration
  -l, --log-console            Log messages to local console
  -D, --log-detail             Detailed log messages
  -S, --log-facility=([0-7]|local[0-7]|user|daemon)
                               Set syslog facility to LOG_LOCAL[0-7], user or daemon (default)
  -G, --no-syslog              Don't log via syslog
  -u, --umask=MASK             umask for file creation (in numeric form)
  -X, --release-vips           Drop VIP on transition from signal.
  -V, --dont-release-vrrp      Don't remove VRRP VIPs and VROUTEs on daemon stop
  -I, --dont-release-ipvs      Don't remove IPVS topology on daemon stop
  -R, --dont-respawn           Don't respawn child processes
  -n, --dont-fork              Don't fork the daemon process
  -d, --dump-conf              Dump the configuration data
  -p, --pid=FILE               Use specified pidfile for parent process
  -r, --vrrp_pid=FILE          Use specified pidfile for VRRP child process
  -T, --genhash                Enter into genhash utility mode (this should be the first option used).
  -c, --checkers_pid=FILE      Use specified pidfile for checkers child process
  -a, --address-monitoring     Report all address additions/deletions notified via netlink
  -s, --namespace=NAME         Run in network namespace NAME (overrides config)
  -m, --core-dump              Produce core dump if terminate abnormally
  -M, --core-dump-pattern=PATN Also set /proc/sys/kernel/core_pattern to PATN (default 'core')
  -e, --all-config             Error if any configuration file missing (same as includet)
  -i, --config-id id           Skip any configuration lines beginning '@' that don't match id
                                or any lines beginning @^ that do match.
                                The config-id defaults to the node name if option not used
      --signum=SIGFUNC         Return signal number for STOP, RELOAD, DATA, STATS, STATS_CLEAR
  -t, --config-test[=LOG_FILE] Check the configuration for obvious errors, output to
                                stderr by default
  -v, --version                Display the version number
  -h, --help                   Display this help message

    可以发现默认有两个配置文件路径 '/usr/local/etc/keepalived/keepalived.conf' or '/etc/keepalived/keepalived.conf'

    但是安装后并没有 /etc/keepalived目录

    稳妥起见,将两个目录进行连接 ln -s /usr/local/etc/keepalived /etc/keepalived

  5. 配置keepalived

    #1号服务器配置
vrrp_script chk_nginx {
        script "/usr/bin/chk_nginx.sh"
        interval 2
}

vrrp_instance VI_1 {
    state MASTER
    nopreempt
    interface ens33
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type AH
        auth_pass 123456
    }
    unicast_src_ip 192.168.175.141
    unicast_peer {
        192.168.175.143
    }

    virtual_ipaddress {
        192.168.175.200
    }
     track_script {
       chk_nginx
    }
}

#2号服务器配置
vrrp_script chk_nginx {
        script "/usr/bin/chk_nginx.sh"
        interval 2
}

vrrp_instance VI_2 {
    state MASTER
    nopreempt
    interface ens33
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type AH
        auth_pass 123456
    }
    unicast_src_ip 192.168.175.143
    unicast_peer {
        192.168.175.141
    }

    virtual_ipaddress {
        192.168.175.200
    }
     track_script {
       chk_nginx
    }
}

    chk_nginx

    #!/bin/bash

# 设置最大重试次数为 5
MAX_RETRIES=5 
RETRY_COUNT=0

# 检查 Nginx 是否在运行中
if [ $(ps -C nginx --no-header |wc -l) -gt 0 ]; then
    echo "Nginx 已经在运行中"
else
    echo "Nginx 未启动，正在启动 Nginx ..."

    # 启动 Nginx
    systemctl start nginx

    # 等待 Nginx 启动完成
    while ! systemctl status nginx.service | grep -q "running"; do
        echo "等待 Nginx 启动完成 ..."
        sleep 1s

        # 检查重试次数是否超过最大重试次数
        RETRY_COUNT=$((RETRY_COUNT + 1))
        if [ $RETRY_COUNT -eq $MAX_RETRIES ]; then
            systemctl stop keepalived.service
            exit 1
        fi
    done
    
    if [ $(ps -C nginx --no-header |wc -l) -gt 0 ]; then
        echo "Nginx 启动完成"
    else
        systemctl stop keepalived.service
        echo "Nginx 启动失败"
    fi
fi

  6. 配置启动服务

    安装后已经配置好了系统服务keepalived.service, 服务位置在/usr/lib/systemd/system目录

    vi /usr/local/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="-f /etc/keepalived/keepalived.conf -D"


    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
Documentation=man:keepalived(8)
Documentation=man:keepalived.conf(5)
Documentation=man:genhash(1)
Documentation=https://keepalived.org

[Service]
Type=forking
PIDFile=/run/keepalived.pid
KillMode=process
# - 表示如果文件不存在则忽略不会报错
EnvironmentFile=-/usr/local/etc/sysconfig/keepalived
# KEEPALIVED_OPTIONS参数在 /usr/local/etc/sysconfig/keepalived文件中配置
ExecStart=/usr/local/sbin/keepalived  $KEEPALIVED_OPTIONS
ExecReload=/bin/kill -HUP $MAINPID

[Install]
WantedBy=multi-user.target

#启动服务
systemctl start keepalived.service 
#设置服务开机启动
systemctl enable keepalived.service

  7. 日志处理

    为keepalived单独写日志文件

    vi /usr/local/etc/sysconfig/keepalived
KEEPALIVED_OPTIONS="-f /etc/keepalived/keepalived.conf -D -S 0"

vi /etc/rsyslog.conf

# rsyslog configuration file

# For more information see /usr/share/doc/rsyslog-*/rsyslog_conf.html
# or latest version online at http://www.rsyslog.com/doc/rsyslog_conf.html 
# If you experience problems, see http://www.rsyslog.com/doc/troubleshoot.html

#### GLOBAL DIRECTIVES ####

# Where to place auxiliary files
global(workDirectory="/var/lib/rsyslog")

# Use default timestamp format
module(load="builtin:omfile" Template="RSYSLOG_TraditionalFileFormat")

#### MODULES ####

module(load="imuxsock" 	  # provides support for local system logging (e.g. via logger command)
       SysSock.Use="off") # Turn off message reception via local log socket; 
			  # local messages are retrieved through imjournal now.
module(load="imjournal" 	    # provides access to the systemd journal
       StateFile="/run/log/imjournal.state") # File to store the position in the journal
#module(load="imklog") # reads kernel messages (the same are read from journald)
#module(load="immark") # provides --MARK-- message capability

$imjournalRatelimitInterval 0

# Include all config files in /etc/rsyslog.d/
include(file="/etc/rsyslog.d/*.conf" mode="optional")
#### RULES ####

# Log all kernel messages to the console.
# Logging much else clutters up the screen.
#kern.*                                                 /dev/console

# Log anything (except mail) of level info or higher.
# Don't log private authentication messages!
*.info;mail.none;authpriv.none;cron.none                /var/log/messages

# The authpriv file has restricted access.
authpriv.*                                              /var/log/secure

# Log all the mail messages in one place.
mail.*                                                  -/var/log/maillog

# Log cron stuff
cron.*                                                  /var/log/cron

# Everybody gets emergency messages
*.emerg                                                 :omusrmsg:*

# Save news errors of level crit and higher in a special file.
uucp,news.crit                                          /var/log/spooler

# Save boot messages also to boot.log
local7.*                                                /var/log/boot.log

# Save keepalived log to keepalived.log
local0.*                                                /var/log/keepalived.log

#重启日志服务: 
systemctl restart rsyslog

#重启keepalived服务 
systemctl restart keepalived.service

#查看日志文件
tail -f /var/log/keepalived.log