如果重装memcache服务器环境后仍不能识别，那么大概率是版本检测失败导致的，可运行以下命令检测：

Quotememcached -V

正常输出如：

Quote# memcached -V
memcached 1.5.7

memcached -V
memcached: error while loading shared libraries: libevent-2.0.so.5: cannot open shared object file: No such file or directory

缺少 libevent-2.0.so.5 文件，可用命令：

Quoteyum provides libevent-2.0.so.5

如：

Quotelibevent2-2.0.21-2.el6.i686 : Abstract asynchronous event notification library
Repo : base
Matched from:
Other : libevent-2.0.so.5

查看下是否有包含这个文件的安装包。