操作系统：CentOS release 5.8 (Final)
Linux localhost.localdomain 2.6.18-308.el5 #1 SMP Tue Feb 21 20:06:06 EST 2012 x86_64 x86_64 x86_64 GNU/Linux
memcached安装命令如下：
yum install memcached
事先已经安装依赖包了。因此上述命令顺利安装。
然后，我要打开memcached：
service memcached start
这时就出现了如下错误：
Starting memcached: chown: `memcached': invalid user
can't find the user memcached to switch to
[FAILED]
我没有对其他文件进行任何修改或配置。
请教一下，这是什么原因？如何解决？谢谢！
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An installation error occurred and a user named memcached was not successfully created. Man useradd yourself and then create it. Maybe a group with the same name is also needed.
Evian’s answer is right.
As for why the user was not created successfully, it is because the user creation function of the system is locked.
[root@203 etc]# lsattr /etc/passwd
------------- /etc/passwd
[root@203 etc]# lsattr /etc/shadow
----i-------- /etc/shadow
[root@203 etc]# lsattr /etc/gshadow
------------- /etc/gshadow
[root@203 etc]# lsattr /etc/group
------------- /etc/group
After I unlocked it and recreated the user, it was successful.
Thank you Evian!