Multiple sites, but subdomain names

https://blog.csdn.net/baidu_3.

I can configure domain
according to his settings, but I want him to change it into a subdomain name
such as
xxx.ccc.com/
. How can I set it?
do you want to transfer the domain name to the same IP?

        ServerName xxx.ccc.com
        DocumentRoot /var/www/xxx

        ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1c1a0c1-32a0d.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1c1a0c1-32a0d.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?