一，Nginx隐藏版本信息
在nginx.conf文件找到http配置，关闭server_tokens，比如

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;
    ........
    ........
    #关闭版本显示
    server_tokens off; 
    ........
    ........
}

重启Nginx即可生效

二，Apache隐藏版本信息
在httpd.conf文件找到ServerTokens，设置为Prod，比如

..............
#
# Don't give away too much information about all the subcomponents
# we are running.  Comment out this line if you don't mind remote sites
# finding out what major optional modules you are running
# 关闭版本显示
ServerTokens Prod

............

Apache版本2.0.44之前的，需要修改多加一行

 ServerSignature Off

官网有说明：
https://httpd.apache.org/docs/2.4/mod/core.html#serversignature

重启Apache即可生效

三，PHP隐藏版本信息
找到php.ini文件，设置expose_php = Off，比如

...........
; Decides whether PHP may expose the fact that it is installed on the server
; (e.g. by adding its signature to the Web server header).  It is no security
; threat in any way, but it makes it possible to determine whether you use PHP
; on your server or not.
; http://php.net/expose-php
# 关闭版本信息
expose_php = Off
........

重启php-fpm即可生效