rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm
[root@web01 ~]# yum repolist all 没看到有webtatic源试了很多次都装不了源
解决:
#rpm -qa |grep webtatic 查看
#rpm -e 删除上面搜的包
#rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm 再执行
#yum search php71 查看yum源是否有php7.1安装包
到此webtatic源就安装上了。

执行安装php软件：
yum install -y php71w php71w-cli php71w-common php71w-devel php71w-embedded  php71w-gd php71w-mcrypt php71w-mbstring php71w-pdo php71w-xml php71w-fpm php71w-mysqlnd php71w-opcache  php71w-pecl-memcached php71w-pecl-redis php71w-pecl-mongodb
报错:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed
字面翻译就是deltarpm没有安装，接下来我们安装就是了
解决:
yum provides ‘*/applydeltarpm‘    #查看依赖包的位置
yum -y  install deltarpm             #安装命令
再执行安装php软件命令，报错：
Downloading packages:
No Presto metadata available for webtatic 没有webtatic元数据
解决:
#yum clean all
#yum makecache