更改test.com.conf
server
{
    listen 80;
    server_name test.com test1.com test2.com;
    index index.html index.htm index.php;
    root /data/wwwroot/test.com;
    if ($host != 'test.com' ) 
    {
        rewrite  http://$host/(.*)$  http://test.com/$1  permanent;
    }
}
// $1就是(.*)括号内的

[root@localhost ~]# curl -x127.0.0.1:80 test2.com/index.html
<html>
<head><title>301 Moved Permanently</title></head>
<body bgcolor="white">
<center><h1>301 Moved Permanently</h1></center>
<hr><center>nginx/1.12.1</center>
</body>
</html>
[root@localhost ~]# curl -x127.0.0.1:80 qq.com/index.html
echo “This is a default site.”
[root@localhost ~]# curl -x127.0.0.1:80 test1.com/index.html
<html>
<head><title>301 Moved Permanently</title></head>
<body bgcolor="white">
<center><h1>301 Moved Permanently</h1></center>
<hr><center>nginx/1.12.1</center>
</body>
</html>