error:while loading shared libraries: libevent-2.1.so.6: cannot open shared object file: No such file or directory

执行 memcached 启动命令时，报错，提示：error while loading shared libraries: libevent-2.1.so.6: cannot open shared object file: No such file or directory

查看 memcached 命令缺失什么库
ldd /usr/local/bin/memcached

查看 libevent-1.2.so.1 是否存在
locate libevent-1.2.so.1

结果： 系统已经安装了该模块，在路径 /usr/local/lib/

查看 memcached 查找依赖库的路径
LD_DEBUG=libs /usr/local/memcached/bin/memcached -v
结果： 在 /lib64/ 目录中查找，所以找不到已经安装好的

映射 libevent-1.2.so.1 到 /lib64 路径中
ln -s /usr/local/lib/libevent-1.2.so.1 /usr/lib64/libevent-1.2.so.1
结果：这样处理后，memcached就可以搜索到该文件了

启动memcached
/usr/local/bin/memcached -d -c  -m  -u root