Post History
Open the Disks application. Select the secondary disk and partition, and in the gears menu click on Edit Mount Options... Uncheck User Session Defaults and uncheck Show in user interface. Opt...
#3: Post edited
Open the _Disks_ application. Select the secondary disk and in the gears menu click on _Edit Mount Options..._- 
Uncheck _Use Session Defaults_ and uncheck _Show in user interface_.- 
- Optional: select a _Mount Point_ you can find easily. The disk will not only not be shown in the dock, it will also not be shown in the file manager anymore as a separate drive, you will have to navigate to the folder yourself.
- You can drag it to the bookmarks for easier navigation:
- 
- Open the _Disks_ application. Select the secondary disk and partition, and in the gears menu click on _Edit Mount Options..._
- 
- Uncheck _User Session Defaults_ and uncheck _Show in user interface_.
- 
- Optional: select a _Mount Point_ you can find easily. The disk will not only not be shown in the dock, it will also not be shown in the file manager anymore as a separate drive, you will have to navigate to the folder yourself.
- You can drag it to the bookmarks for easier navigation:
- 
#2: Post edited
- Open the _Disks_ application. Select the secondary disk and in the gears menu click on _Edit Mount Options..._
- 
Unselect _Use Session Defaults_ and uncheck _Show in user interface_.- 
Optional: select a _Mount Point_ you can find easily. The disk will not only be shown in the dock, it will also not be shown in the file manager anymore as a separate drive, you will have to navigate to the folder yourself.- You can drag it to the bookmarks for easier navigation:
- 
- Open the _Disks_ application. Select the secondary disk and in the gears menu click on _Edit Mount Options..._
- 
- Uncheck _Use Session Defaults_ and uncheck _Show in user interface_.
- 
- Optional: select a _Mount Point_ you can find easily. The disk will not only not be shown in the dock, it will also not be shown in the file manager anymore as a separate drive, you will have to navigate to the folder yourself.
- You can drag it to the bookmarks for easier navigation:
- 
#1: Initial revision
Open the _Disks_ application. Select the secondary disk and in the gears menu click on _Edit Mount Options..._  Unselect _Use Session Defaults_ and uncheck _Show in user interface_.  Optional: select a _Mount Point_ you can find easily. The disk will not only be shown in the dock, it will also not be shown in the file manager anymore as a separate drive, you will have to navigate to the folder yourself. You can drag it to the bookmarks for easier navigation: 