Zabbix reset password

Change the Admin account for the zabbix GUI password on a system with a postgreSQL database

Logon to the postgreSQL with:
   sudo su postgres psql

In case you don't remember the user name also use:
   select * from users;

Connect to the zabbix database
   \c zabbix

Change the password of the Admin user to a blank one:
    update users set passwd=md5('') where alias='Admin';

You can verify this has worked by checking the password hash for the Admin user is the same as the guest user by listing the users in the users table:
    select * from users;

NB. Logout from postgreSQL with
   \q

If it’s the same hash you should then be able to logon to the GUI with ‘Admin’ and a blank password (hopefully!) and change your password within the web GUI - hurrah!

If not you may need to restart the zabbix server service. On Ubuntu 16 it’s:

service zabbix-server restart