title: what does unauthenticated user mean in MYSQL?
body: <pre><code>mysql&gt; show full processlist;
  +-----+----------------------+--------------------+------+---------+------+----------------------------------+-----------------------+
  | Id  | User                 | Host               | db   | Command | Time | State                            | Info                  |
  +-----+----------------------+--------------------+------+---------+------+----------------------------------+-----------------------+
  |   1 | system user          |                    | NULL | Connect |  623 | Waiting for master to send event | NULL                  | 
  |   2 | system user          |                    | NULL | Connect |    0 | Reading event from the relay log | NULL                  | 
  | 400 | root                 | localhost          | v3   | Sleep   |   68 |                                  | NULL                  | 
  | 585 | root                 | localhost          | v3   | Query   |    0 | NULL                             | show full processlist | 
  | 748 | unauthenticated user | 172.19.0.27:32833  | NULL | Connect | NULL | login                            | NULL                  | 
  | 749 | unauthenticated user | 172.19.0.27:32836  | NULL | Connect | NULL | login                            | NULL                  | 
  | 750 | unauthenticated user | 172.19.0.27:32838  | NULL | Connect | NULL | login                            | NULL                  | 
  | 751 | unauthenticated user | 172.19.0.27:32841  | NULL | Connect | NULL | login                            | NULL                  | 
  | 752 | unauthenticated user | 172.19.0.27:32844  | NULL | Connect | NULL | login                            | NULL                  | 
  | 753 | unauthenticated user | 172.19.0.27:32846  | NULL | Connect | NULL | login                            | NULL                  | 
  | 754 | unauthenticated user | 172.19.0.27:32848  | NULL | Connect | NULL | login                            | NULL                  | 
  | 755 | unauthenticated user | 172.19.0.139:46827 | NULL | Connect | NULL | login                            | NULL                  | 
  | 756 | unauthenticated user | 172.19.0.139:46830 | NULL | Connect | NULL | login                            | NULL                  | 
  | 757 | unauthenticated user | 172.19.0.139:46831 | NULL | Connect | NULL | login                            | NULL                  | 
  | 758 | unauthenticated user | 172.19.0.27:32857  | NULL | Connect | NULL | login                            | NULL                  | 
  | 759 | unauthenticated user | 172.19.0.27:32858  | NULL | Connect | NULL | login                            | NULL                  | 
  | 760 | unauthenticated user | 172.19.0.27:32859  | NULL | Connect | NULL | login                            | NULL                  | 
  | 761 | unauthenticated user | 172.19.0.27:32863  | NULL | Connect | NULL | login                            | NULL                  | 
  | 762 | unauthenticated user | 172.19.0.27:32864  | NULL | Connect | NULL | login                            | NULL                  | 
  | 763 | unauthenticated user | 172.19.0.27:32866  | NULL | Connect | NULL | login                            | NULL                  | 
  | 764 | unauthenticated user | 172.19.0.27:32870  | NULL | Connect | NULL | login                            | NULL                  | 
  | 765 | unauthenticated user | 172.19.0.27:32871  | NULL | Connect | NULL | login                            | NULL                  | 
  | 766 | unauthenticated user | 172.19.0.139:46833 | NULL | Connect | NULL | login                            | NULL                  | 
  | 767 | unauthenticated user | 172.19.0.27:32878  | NULL | Connect | NULL | login                            | NULL                  | 
  | 768 | unauthenticated user | 172.19.0.27:32881  | NULL | Connect | NULL | login                            | NULL                  | 
  | 769 | unauthenticated user | 172.19.0.27:32885  | NULL | Connect | NULL | login                            | NULL                  | 
  | 770 | unauthenticated user | 172.19.0.139:46835 | NULL | Connect | NULL | login                            | NULL                  | 
  | 771 | unauthenticated user | 172.19.0.27:32888  | NULL | Connect | NULL | login                            | NULL                  | 
  | 772 | unauthenticated user | 172.19.0.27:32890  | NULL | Connect | NULL | login                            | NULL                  | 
  | 773 | unauthenticated user | 172.19.0.139:46837 | NULL | Connect | NULL | login                            | NULL                  | 
  | 774 | unauthenticated user | 172.19.0.139:46839 | NULL | Connect | NULL | login                            | NULL                  | 
  | 775 | unauthenticated user | 172.19.0.139:46841 | NULL | Connect | NULL | login                            | NULL                  | 
  | 776 | unauthenticated user | 172.19.0.139:46844 | NULL | Connect | NULL | login                            | NULL                  | 
  | 777 | unauthenticated user | 172.19.0.139:46845 | NULL | Connect | NULL | login                            | NULL                  | 
  | 778 | unauthenticated user | 172.19.0.139:46847 | NULL | Connect | NULL | login                            | NULL                  | 
  | 779 | unauthenticated user | 172.19.0.27:32898  | NULL | Connect | NULL | login                            | NULL                  | 
  | 780 | unauthenticated user | 172.19.0.27:32900  | NULL | Connect | NULL | login                            | NULL                  | 
  | 781 | unauthenticated user | 172.19.0.139:46850 | NULL | Connect | NULL | login                            | NULL                  | 
  | 782 | unauthenticated user | 172.19.0.139:46852 | NULL | Connect | NULL | login                            | NULL                  | 
  | 783 | unauthenticated user | 172.19.0.139:46854 | NULL | Connect | NULL | login                            | NULL                  | 
  | 784 | unauthenticated user | 172.19.0.139:46857 | NULL | Connect | NULL | login                            | NULL                  | 
  | 785 | unauthenticated user | 172.19.0.139:46859 | NULL | Connect | NULL | login                            | NULL                  | 
  | 786 | unauthenticated user | 172.19.0.27:32903  | NULL | Connect | NULL | login                            | NULL                  | 
  | 787 | unauthenticated user | 172.19.0.139:46862 | NULL | Connect | NULL | login                            | NULL                  | 
  | 788 | unauthenticated user | 172.19.0.139:46865 | NULL | Connect | NULL | login                            | NULL                  | 
  | 789 | unauthenticated user | 172.19.0.139:46866 | NULL | Connect | NULL | login                            | NULL                  | 
  | 790 | unauthenticated user | 172.19.0.139:46868 | NULL | Connect | NULL | login                            | NULL                  | 
  | 791 | unauthenticated user | 172.19.0.139:46871 | NULL | Connect | NULL | login                            | NULL                  | 
  | 792 | unauthenticated user | 172.19.0.139:46873 | NULL | Connect | NULL | login                            | NULL                  | 
  | 793 | unauthenticated user | 172.19.0.27:32907  | NULL | Connect | NULL | login                            | NULL                  | 
  | 794 | unauthenticated user | 172.19.0.27:32909  | NULL | Connect | NULL | login                            | NULL                  | 
  | 795 | unauthenticated user | 172.19.0.27:32911  | NULL | Connect | NULL | login                            | NULL                  | 
  | 796 | unauthenticated user | 172.19.0.139:46875 | NULL | Connect | NULL | login                            | NULL                  | 
  | 797 | unauthenticated user | 172.19.0.27:32914  | NULL | Connect | NULL | login                            | NULL                  | 
  | 798 | unauthenticated user | 172.19.0.27:32916  | NULL | Connect | NULL | login                            | NULL                  | 
  | 799 | unauthenticated user | 172.19.0.139:46877 | NULL | Connect | NULL | login                            | NULL                  | 
  | 800 | unauthenticated user | 172.19.0.139:46879 | NULL | Connect | NULL | login                            | NULL                  | 
  +-----+----------------------+--------------------+------+---------+------+----------------------------------+-----------------------+
  57 rows in set (0.00 sec)
  </code></pre>