I have a Greenbone OS version 6.07.
On the upgrade page from version 6 to version 20.8 ( https://docs.greenbone.net/GSM-Manual/gos-20.08/en/upgrading-gos.html) guides you to select maintenance and then upgrade, but the upgrade option is not available.
In the initial guidelines it states: Before upgrading to GOS 20.08, the latest version of GOS 6 must be installed on the GSM and the GSM must be rebooted.
So I would like to know how to update to the latest version of GOS 6 so that I can then upgrade to version 20.8
Or is there some way to upgrade directly from version 6.07 to version 20.8
Thank you for any help.