I believe it is cpanel running tests if ftp is working.
Lock Down Reviewed by Lock Down on . Constant pure-ftpd new connection 127.0.0.1 messages just got a new server and message logs are filled with this every 8 minutes: pure-ftpd: (?@127.0.0.1) New connection from 127.0.0.1 pure-ftpd: (?@127.0.0.1) Logout. pure-ftpd: (?@127.0.0.1) New connection from 127.0.0.1 pure-ftpd: (?@127.0.0.1) Logout. pure-ftpd: (?@127.0.0.1) New connection from 127.0.0.1 pure-ftpd: (?@127.0.0.1) Logout. pure-ftpd: (?@127.0.0.1) New connection from 127.0.0.1 pure-ftpd: (?@127.0.0.1) Logout. Rating: 5