I also checked mysql table like this:

mysql> select * from sessions;
+----------------------------------+----------------------------------
+-------------------------------------------------+
| id                               | a_session                        
+                                                 |
+----------------------------------+----------------------------------
+-------------------------------------------------+
| e6a5ed9dd1afc80ad115097e97ea7e5c |    
 e6a5ed9dd1afc80ad115097e97ea7e5c   
                                    _session_id
security_code |
| abe1ec864cf636ea147b8982331fc211 |    
 abe1ec864cf636ea147b8982331fc211   
                                    _session_id
security_code |
| 4a926009da58be40afdad7baef41d9e4 |    
 4a926009da58be40afdad7baef41d9e4   
                                    _session_id
security_code |
| 7a65f897282e294c9153892395dfe84c |    
 7a65f897282e294c9153892395dfe84c   
                                    _session_id
security_code |
+----------------------------------+----------------------------------
+-------------------------------------------------+
4 rows in set (0.00 sec)
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