1. 查看当前安装php信息

# 版本
php -v
# 所安装的软件包
php yum list installed | grep php

2. 更换当前RPM源

rpm -Uvh https://mirror.webtatic.com/yum/el7/epel-release.rpm
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm

3. 停止当前php服务

systemctl start php-fpm

# 或是直接针对pid
kill -INT 'cat /xxx/php-fpm.pid'

4. 对当前安装的php软件包执行remove

# 使用 * 通配符
yum remove php*

5. 卸载旧版本后,保证安装以下源

# EPEL源
yum install epel-release

# REMI源
yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm  

# Yum 源工具
yum install yum-utils

6. 安装php7.3

yum install -y php73-php-fpm php73-php-cli php73-php-bcmath php73-php-gd php73-php-json php73-php-mbstring php73-php-mcrypt php73-php-mysqlnd php73-php-opcache php73-php-pdo php73-php-pecl-crypto php73-php-pecl-mcrypt php73-php-pecl-geoip php73-php-recode php73-php-snmp php73-php-soap php73-php-xml

7. 查看版本以及启动

php73 -v

# 开机自启
systemctl enable php-fpm
# 启动
systemctl start php-fpm