1:进入终端后查看PHP版本
php -v
输出可能如下：
PHP 5.4.35 (cli) (built: Nov 14 2014 07:04:10) Copyright (c) 1997-2014 The PHP Group Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies with Zend OPcache v7.0.4-dev, Copyright (c) 1999-2015, by Zend Technologies
2:执行下面的命令升级软件仓库
rpm -Uvh https://mirror.webtatic.com/yum/el7/epel-release.rpm
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
3:执行下面的命令删除php
yum remove php-common
然后像安装那样问你是否继续的，输入yes即可
4:安装php 5.6版本（php56w-devel这个不是必需的）
yum install -y php56w php56w-opcache php56w-xml php56w-mcrypt php56w-gd php56w-devel php56w-MySQL php56w-intl php56w-mbstring
5:重启httpd
service httpd restart
查看最新的版本
php -v
现在应该是5.6了！
㈡ 阿里云上的centos 7.2怎么yum安装php 5.6
因之前通过网易的 centos 镜像，将阿里云的 centos 升级到最新版了，乘自己的项目尚未开始正式开发，遂将所有的相应环境都升级到最高。
查看 centos 版本：
[root@iZ23d ~]# cat /etc/centos-release
CentOS Linux release 7.2.1511 (Core)
1、删除之前的 php 版本：
[root@iZ23d ~]# yum remove php* php-common
Loaded plugins: langpacks
Repository base is listed more than once in the configuration
Repository updates is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
No Match for argument: php-5.4.16
No Match for argument: php-5.4.16.tar.gz
No Match for argument: php-7.0.1RC1
No Match for argument: php-7.0.1RC1.tar.gz
No Match for argument: phpMyAdmin-4.4.0.tar.gz
No Match for argument: php-common
No Packages marked for removal
2、rpm 安装 Php7 相应的 yum源：
[root@iZ23d ~]# rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
Retrieving https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
warning: /var/tmp/rpm-tmp.LhJKKR: Header V4 RSA/SHA1 Signature, key ID 62e74ca5: NOKEY
Preparing... ################################# [100%]
package webtatic-release-7-3.noarch is already installed
3、 直接yum安装php7：
[root@iZ23d ~]# yum install php70w
Loaded plugins: langpacks
Repository base is listed more than once in the configuration
Repository updates is listed more than once in the configuration
Repository extras is listed more than once in the configuration
Repository centosplus is listed more than once in the configuration
Resolving Dependencies
--> Running transaction check
。。。 【省略】
Warning: RPMDB altered outside of yum.
Installing : php70w-common-7.0.0-1.w7.x86_64 1/3
Installing : php70w-cli-7.0.0-1.w7.x86_64 2/3
Installing : php70w-7.0.0-1.w7.x86_64 3/3
Verifying : php70w-7.0.0-1.w7.x86_64 1/3
Verifying : php70w-common-7.0.0-1.w7.x86_64 2/3
Verifying : php70w-cli-7.0.0-1.w7.x86_64 3/3
Installed:
php70w.x86_64 0:7.0.0-1.w7
Dependency Installed:
php70w-cli.x86_64 0:7.0.0-1.w7 php70w-common.x86_64 0:7.0.0-1.w7
Complete!
4、检查 php 版本：
[root@iZ23d ~]# php -v
PHP 7.0.0 (cli) (built: Dec 2 2015 20:42:32) ( NTS )
Copyright (c) 1997-2015 The PHP Group
Zend Engine v3.0.0, Copyright (c) 1998-2015 Zend Technologies
[root@iZ23d2e6hoqZ ~]#
以上显示安装成功！
5、重启 Apache，查看 phpinfo :
[root@iZ23d ~]# systemctl restart httpd.service
检查phpinfo:
PHP Version 7.0.0
SystemLinux iZ23d 3.10.0-229.11.1.el7.x86_64 #1 SMP Thu Aug 6 01:06:18 UTC 2015 x86_64
Build DateDec 2 2015 20:43:38
Server APIApache 2.0 Handler
Virtual Directory Supportdisabled
Configuration File (php.ini) Path/etc
Loaded Configuration File/etc/php.ini
Scan this dir for additional .ini files/etc/php.d
Additional .ini files parsed/etc/php.d/bz2.ini, /etc/php.d/calendar.ini, /etc/php.d/ctype.ini, /etc/php.d/curl.ini, /etc/php.d/exif.ini, /etc/php.d/fileinfo.ini, /etc/php.d/ftp.ini, /etc/php.d/gettext.ini, /etc/php.d/gmp.ini, /etc/php.d/iconv.ini, /etc/php.d/json.ini, /etc/php.d/phar.ini, /etc/php.d/shmop.ini, /etc/php.d/simplexml.ini, /etc/php.d/sockets.ini, /etc/php.d/tokenizer.ini, /etc/php.d/xml.ini, /etc/php.d/zip.ini
PHP API20151012
PHP Extension20151012
Zend Extension320151012
Zend Extension BuildAPI320151012,NTS
PHP Extension BuildAPI20151012,NTS
Debug Buildno
Thread Safetydisabled
Zend Signal Handlingdisabled
Zend Memory Managerenabled
Zend Multibyte Supportdisabled
IPv6 Supportenabled
DTrace Supportenabled
Registered PHP Streamshttps, ftps, compress.zlib, php, file, glob, data, http, ftp, compress.bzip2, phar, zip
Registered Stream Socket Transportstcp, udp, unix, udg, ssl, sslv3, sslv2, tls, tlsv1.0, tlsv1.1, tlsv1.2
Registered Stream Filterszlib.*, string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed, dechunk, bzip2.*, convert.iconv.*
This program makes use of the Zend Scripting Language Engine:
Zend Engine v3.0.0, Copyright (c) 1998-2015 Zend Technologies
Configuration
apache2handler
Apache VersionApache/2.4.6 (CentOS)
Apache API Version20120211
Server [email protected]
Hostname:Portxxxx.xxxxx.xxx:0
User/Groupapache(48)/48
Max RequestsPer Child: 0 - Keep Alive: on - Max Per Connection: 100
TimeoutsConnection: 60 - Keep-Alive: 15
Virtual ServerYes
Server Root/etc/httpd
Loaded Molescore mod_so http_core mod_access_compat mod_actions mod_alias mod_allowmethods mod_auth_basic mod_auth_digest mod_authn_anon mod_authn_core mod_authn_dbd mod_authn_dbm mod_authn_file mod_authn_socache mod_authz_core mod_authz_dbd mod_authz_dbm mod_authz_groupfile mod_authz_host mod_authz_owner mod_authz_user mod_autoindex mod_cache mod_cache_disk mod_data mod_dbd mod_deflate mod_dir mod_mpio mod_echo mod_env mod_expires mod_ext_filter mod_filter mod_headers mod_include mod_info mod_log_config mod_logio mod_mime_magic mod_mime mod_negotiation mod_remoteip mod_reqtimeout mod_rewrite mod_setenvif mod_slotmem_plain mod_slotmem_shm mod_socache_dbm mod_socache_memcache mod_socache_shmcb mod_status mod_substitute mod_suexec mod_unique_id mod_unixd mod_userdir mod_version mod_vhost_alias mod_dav mod_dav_fs mod_dav_lock mod_lua prefork mod_proxy mod_lbmethod_bybusyness mod_lbmethod_byrequests mod_lbmethod_bytraffic mod_lbmethod_heartbeat mod_proxy_ajp mod_proxy_balancer mod_proxy_connect mod_proxy_express mod_proxy_fcgi mod_proxy_fdpass mod_proxy_ftp mod_proxy_http mod_proxy_scgi mod_proxy_wstunnel mod_ssl mod_systemd mod_cgi mod_perl mod_php7
以上显示 php7 安装成功！
㈢ linux yum安装php7.3
先安装前面的教程，再安装后面的
参考教程1：
https://blog.csdn.net/weixin_43731793/article/details/91488289
参考教程2：
http://www.bubuko.com/infodetail-2931909.html
安装PHP
1、安装PHP73
1.1、卸载旧版本PHP
yum remove php*
1.2、安装EPEL：
sudo yum install epel-release
1.3、安装remi（选一个）:
sudo rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-7.rpm
rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
1.4、查看目前有php的什么版本（可忽略）
sudo yum list php*
1.5、列出所有的php相关的rpm包（可忽略）
rpm -qa|grep php
1.6、删除php相关的rpm包（一次只能删除一个）（可忽略）
rpm -e php72w-mysqlnd-7.2.17-1.w7.x86_64
1.7、列出remi仓库下所有PHP7.3可用模块。（可忽略）
yum --enablerepo=remi-php73 search php | grep php73
1.8、安装PHP 7.3
yum --enablerepo=remi-php73 install php
1、安装 PHP7.3：
（解决yum安装apache关联不了PHP的问题，用以下命令安装）
yum --enablerepo=remi-php73 install php
安装模块
yum --enablerepo=remi-php73 install 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
2、设置开机启动、运行服务：
systemctl enable php73-php-fpm
systemctl start php73-php-fpm
3、查找php.ini位置：
find /etc/opt/remi/php73 -name php.ini
/etc/opt/remi/php73/php.ini
找到apache的配置文件：httpd.conf
sudo find / -name httpd.conf
位置如下：
/etc/httpd/conf/httpd.conf
5、PHP日常操作
systemctl restart php73-php-fpm #重启
systemctl start php73-php-fpm #启动
systemctl stop php73-php-fpm #关闭
systemctl status php73-php-fpm #检查状态
php -m #查看PHP已安装拓展模块
php -v #查看PHP版本
㈣ 在linux安装PHP需要把原来的版本删除吗
用yum安装的最好是删掉比较好，自己编译安装的可以不用删，但还是最好备份一下之前版本配置，还有版本切换的时候记得，扩展要同时更新。
㈤ linux centos 7 下用yum 安装iso镜像里自带的php5.4.16版本的但是没有php-fqm文件不知道怎么重启php服务
systemctl restart php-fpm.service #这条命令是重启php服务
下面是一个比较靠谱的php安装步骤：
先删除已有的php版本 ，执行下面的命令删除php
yum remove php-common
然后像安装那样问你是否继续的，输入yes即可
添加 yum 源
CentOS 6.x 的源
# rpm -Uvh http://download.Fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
# rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
安装 PHP
# yum install --enablerepo=remi,remi-php56 php php-opcache php-pecl-apcu php-devel php-mbstring php-mcrypt php-mysqlnd php-phpunit-PHPUnit php-pecl-xdebug php-pecl-xhprof php-pdo php-pear php-fpm php-cli php-xml php-bcmath php-process php-gd php-common
注：安装5.6版本为remi-php56,安装5.5版本为remi-php55