应用场景：使用Keepalived + Nginx，搭建两台（主、备）软负载服务器。

脚本功能：

1）磁盘分区，创建PV、VG、LV，磁盘格式化，文件系统挂载；

2）安装依赖包；

3）安装和配置（提前配置好的文件）Nginx、Keepalived；

4）启动相关服务；

测试环境：

1）虚拟机单独挂载了一块/dev/vdb的独立磁盘（50GB）作为数据盘，与系统盘分开；

2）系统提前挂载了在线的yum源；

3）提前准备好相关的配置文件，如：nginx.conf、keepalived.conf、chk_nginx.sh；

#! /bin/bash

####################################################
#
# Function: install nginx and keepalived
# version: 1.0
# Date: 2022/11/9
#
####################################################

echo "=============================="
PS3="chose which disk you want to create:"
select W in `ls /dev/vd*|grep -o 'vd[b-z]'|uniq` quit
do
        case $W in
        vda)
            fdisk -l /dev/vda
            break;;
        vd[b-z])
             echo "n
                     p



                        t
                         8e
                           w" | fdisk /dev/$W
        break;;
        quit)
        break;;
        *)
        echo "Wrong disk choice, check again!";;
        esac
done

pvcreate /dev/vdb1
vgcreate vg /dev/vdb1
lvcreate -L 49.9G -n data vg
mke2fs -t ext4 -b 4096 /dev/vg/data
cd /
mkdir data
mount  /dev/vg/data /data

cat >> /etc/fstab << EOF
/dev/mapper/vg-data      /data                  ext4      defaults        0 0
EOF

echo "Start to install dependent rpms by on-line yum."
yum install -y curl gcc gcc-c++ libnl libnl-devel libnl3-devel libnfnetlink-devel net-snmp-devel openssl openssl-devel patch pcre pcre-devel telnet zlib zlib-devel

nginx_version=1.22.1
keepalived_version=2.2.7
work_dir=/usr/local/src

cd $work_dir
echo "Start to install Nginx-"${nginx_version}".tar.gz"
tar -xzf ./nginx-${nginx_version}.tar.gz
rm -f ./nginx-${nginx_version}.tar.gz

echo "Start to configure and install nginx-"${nginx_version}
cd ./nginx-${nginx_version}
./configure --prefix=/data/nginx --with-threads
make
make install

cp -f $work_dir/master/nginx.conf /data/nginx/conf
cp -f $work_dir/html/403.html /data/nginx/html
cp -f $work_dir/html/404.html /data/nginx/html
mv /data/nginx/html/index.html /data/nginx/html/index_html

echo "Start to install keepalived-"${keepalived_version}".tar.gz"
mkdir -p /usr/local/keepalived /etc/keepalived
cd $work_dir
tar -xzf ./keepalived-${keepalived_version}.tar.gz
rm -f ./keepalived-${keepalived_version}.tar.gz

cd $work_dir/keepalived-${keepalived_version}
./configure --prefix=/usr/local/keepalived --sysconfdir=/etc/keepalived
make
make install

cp -f $work_dir/common/keepalived.service /usr/lib/systemd/system/
systemctl daemon-reload
systemctl enable keepalived.service

cp -f $work_dir/master/keepalived.conf /etc/keepalived/
cp -f $work_dir/common/chk_nginx.sh /etc/keepalived/
chmod u+x /etc/keepalived/chk_nginx.sh

cp $work_dir/keepalived-2.2.7/keepalived/etc/init.d/keepalived /etc/init.d
cp $work_dir/keepalived-2.2.7/keepalived/etc/sysconfig/keepalived /etc/sysconfig
cp $work_dir/keepalived-2.2.7/keepalived/etc/keepalived/keepalived.conf.sample /etc/keepalived
cp $work_dir/keepalived-2.2.7/bin/keepalived /usr/sbin

systemctl enable keepalived.service
systemctl start keepalived.service
systemctl status keepalived.service

备注：这个脚本本身并没有什么技术含量，但是通过这个脚本可以将大约三个小时（两台虚拟机）的手工安装操作时长，缩减到5至10分钟。另外，频繁的安装，确实很无聊，所以抽了点时间做成脚本。

附：Nginx软负载典型架构图