面试中问到这个问题，之前做过tomcat的登陆认证，nginx如下：
-- 使用模块：
ngx_http_auth_basic_module ：实现让用户只有输入正确的用户名密码才允许访问web内容
-- 安装httpd工具：
yum -y install httpd
-- 用命令htpasswd生成密码文件：-c指定密码文件，后面自定义登陆的用户名
htpasswd -c /etc/nginx/passwd nginxuser
--配置nginx：
配置文件server内新增加如下两行：
auth_basic "Please input password"; #这里是验证时的提示信息 auth_basic_user_file /etc/nginx/passwd;
nginx -t #验证配置OK
service nginx restart #重启生效
--附htpasswd命令：
Usage:
htpasswd [-cimBdpsDv] [-C cost] passwordfile username
htpasswd -b[cmBdpsDv] [-C cost] passwordfile username password
htpasswd -n[imBdps] [-C cost] username
htpasswd -nb[mBdps] [-C cost] username password
-c Create a new file.
-n Don't update file; display results on stdout.
-b Use the password from the command line rather than prompting for it.
-i Read password from stdin without verification (for script usage).
-m Force MD5 encryption of the password (default).
-B Force bcrypt encryption of the password (very secure).
-C Set the computing time used for the bcrypt algorithm
(higher is more secure but slower, default: 5, valid: 4 to 31).
-d Force CRYPT encryption of the password (8 chars max, insecure).
-s Force SHA encryption of the password (insecure).
-p Do not encrypt the password (plaintext, insecure).
-D Delete the specified user.
-v Verify password for the specified user.
On other systems than Windows and NetWare the '-p' flag will probably not work.
The SHA algorithm does not use a salt and is less secure than the MD5 algorithm.
