①检查安装PHP所需的lib库

检查是否安装了以下lib库
[root@iZ2zef32qxgaqdo7w2m844Z ~]# rpm -qa zlib-devel libxml2-devel libjpeg libjpeg-turbo-devel libiconv-devel
zlib-devel-1.2.3-29.el6.x86_64
[root@iZ2zef32qxgaqdo7w2m844Z ~]# rpm -qa freetype-devel libpng-devel gd-devel libcurl-devel libxslt-devel

逐一安装没有安装的lib库
[root@iZ2zef32qxgaqdo7w2m844Z ~]# yum install zlib-devel libxml2-devel libjpeg-devel libjpeg-turbo-devel libiconv-devel -y
[root@iZ2zef32qxgaqdo7w2m844Z ~]# yum install freetype-devel libpng-devel gd-devel libcurl-devel libxslt-devel libxslt-devel -y

安装yum无法安装的libiconv库
[root@iZ2zef32qxgaqdo7w2m844Z ~]# mkdir -p /home/kxzl/tools
[root@iZ2zef32qxgaqdo7w2m844Z ~]# cd /home/kxzl/tools
[root@iZ2zef32qxgaqdo7w2m844Z tools]# wget https://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.15.tar.gz
[root@iZ2zef32qxgaqdo7w2m844Z tools]# tar zxf libiconv-1.15.tar.gz
[root@iZ2zef32qxgaqdo7w2m844Z tools]# cd libiconv-1.15
[root@iZ2zef32qxgaqdo7w2m844Z libiconv-1.15]# ./configure --prefix=/usr/local/libiconv
[root@iZ2zef32qxgaqdo7w2m844Z libiconv-1.15]# make
[root@iZ2zef32qxgaqdo7w2m844Z libiconv-1.15]# make install


安装libmcrypt库
[root@iZ2zef32qxgaqdo7w2m844Z ~]# cd /home/kxzl/tools
[root@iZ2zef32qxgaqdo7w2m844Z tools]# wget -O/etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-6.repo
[root@iZ2zef32qxgaqdo7w2m844Z tools]# yum -y install libmcrypt-devel

如果安装失败，请考虑下载
wget -O/etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo