Correspnding Key

Asked by Badrinath on 2020-06-22

Hi Cubic Team,

I need some clarification in regards to the corresponding key. when i want to add the PPA respository manually, it says to put the corresponding key.

Please let me know why should i have to enter this key and what this does.

sudo apt-key adv --keyserver

Thanks and Regards

Badrinath V

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Badrinath (badrinak) said : #1

Hi Team,

It seems no one is interested to help.


Badrinath V

Cubic PPA (cubic-wizard) said : #2

This sounds like a general Linux question about adding PPAs.
Could you add more context?
What PPA are you trying to add?
How did you add the PPA?
Perhaps you can share your commands and the output?

Badrinath (badrinak) said : #3

Hi Cubic,

I am sorry this is very generic question adding PPA to install Cubic. In your says that if you manually add the PPA repository you need to add the key.

I might sound stupid..just to check why should i put the key in, cubic does not work without the key ?

(If you manually add these reposities, be sure to add the corresponding key:

    $ sudo apt-key adv --keyserver --recv-keys B7579F80E494ED3406A59DF9081525E2B4F1283B )

Cubic PPA (cubic-wizard) said : #4

The purpose of the key is to tell apt that you trust the repository and it is OK for apt to install software on your system from that repository. Apt uses this key to verify that the software is authentic and has not been modified by a third party.

When you use `apt-add-repository`, the corresponding key for the repository is automatically added.
However, if you manually add the repository, then you must also manually add the repository's key.

In order to protect your system, apt will not install software from a repository without the repository's trusted key.
This is true for all PPAs, as well as the Cubic PPA (ppa:cubic-wizard).
Therefore you will not be able to *install* Cubic without this key.

The man page for apt says, "apt-key is used to manage the list of keys used by apt to authenticate packages. Packages which have been authenticated using these keys will be considered trusted." (From

All PPAs that you use on your system must have trusted keys installed.
To see a list of trusted keys on your system, execute:
    $ apt-key list
This command will list both automatically added keys (using `apt-add-repository`) and manually added keys (using `apt-key`).

Here is a good resource if you need more information...

Cubic PPA (cubic-wizard) said : #5

Small correction:

Apt does allow you to install unauthenticated packages, but it will warn you first:

    "Install these packages without verification [y/N]?"

Badrinath (badrinak) said : #6

Hi Cubic,

This was helpfull, Thank you for guiding me.

another question in regards to windows domain joining.

Can we integrate Realmd and ssssd within our cubic ISO?

Is there any doc which it gives guides how to to?

Thanks and Regards,

Badrinath Khakde V

Badrinath (badrinak) said : #7

Thank you that answered my questions.

Badrinath V