Pre-flight checks

Access to the Web GUI
Access to the terminal through SSH
Zulip and Gitlab are running on it, so needed to communicate first on Organisational channel, to make sure everyone has read and agreed on it.

Rebooting

Make sure all the pre flight checks are done
Make an schedule for doing the rebootng.
Create a maintenance period on Zabbix with all the vms are running on Offsite and Offsite itself
Make sure the maintenance is active (yellow icon)
Update the packages through terminal `apt update` and `apt upgrade`
Make sure that the packages are removed, upgraded and installed correctly and check them
Click the reboot button for the Offsite in the web GUI
Check if it is actually shut down
Wait till it comes online again
On Zabbix, go to 'Configuration' -> 'all the vms', and click on 'items' for the rebooted vms.
Search for 'reboot', select the checkbox for both items and click on 'Execute now'.
Search for 'operating', select the checkbox for the item that has a trigger that uses it, and select 'Execugte now'.
Go to 'Monitoring' -> 'Problems'. Check the checkbox for triggers that fired for this host. Expected are '<host> has been restarted' and 'Operating system description has changed'. Scroll to the bottom and click on 'Mass update'. In the modal, check the checkbox for 'close problem', 'acknowledge', and in the 'message' box write the reason the host was rebooted. For example 'host was rebooted due to kernel update'
Remove the maintenance period from the vm