Ubuntu 13.10: Gnome-Terminal log in as su fails

[Michael Lanczak]

Gnome-Terminal: If you try to log in as superuser with the order 'su' the input of any passwords fails.
You are not able for using the Gnome-Terminal as superuser like the Ubuntu-version 12.04 LTS.

[Gunnar Hjalmarsson (gunnarhj)]

Hi Michael,

To be honest I don't quite understand what you say. But in any case it does not seem to be about an issue with the documentation.

Can you possibly explain a little more, so we can change the affected package to something more correct.

[Daniel Dyla (dyladan)]

Correct me if i'm wrong but I was under the impression that login as root was disabled by default in Ubuntu. In order to do it you need to use sudo to give yourself root permissions (which then let you log in as any user).

Try this:

sudo su

[Michael Lanczak (esddss)]

1. Start the Gnome-Terminal. You get 'user@host:~> ' .
2. Type 'su' , then you get the call to give your root password.
3. I type my root password, which I use as superuser (fixed by installing Ubuntu-system as root and log in to the operating system Ubuntu!).
4. I get the alert: 'Error with authenticity'(of the user, in German: 'Fehler bei der Authentifizierung').

I tried it with the order 'sudo su'. Here I get the entry as root (superuser 'root@host:~> ')!
But 'sudo' is an order for only a time limit (or helps 'sudo -v su'?). A little circumstantial.
In earlier versions of Ubuntu like the Ubuntu-version 12.04 LTS and also Suse Linux you need only the order 'su' and your root-password for entering as superuser for unlimited time.

[Gunnar Hjalmarsson (gunnarhj)]

Hi Michael,

As Daniel said, by default you can't log in as root in Ubuntu (at least not any longer).

Please see https://help.ubuntu.com/community/RootSudo

[Michael Lanczak (esddss)]

I want something give to mind and discussion referring to 'sudo' with 'su':

If you want to execute a securing backup of a complete drive or partition (so like sda...), then you need more time as a few seconds or minutes. (By the way, so you are able to restore your system and data if at example the harddisk is damaged and you must install a new harddisk.)
For that you need root authority, which you get only in terminal (or other possibility?) with the command 'su'.
For a root-partition with 20 GB space you need for a backup roughly 13 minutes, for a home-partition more, for a complete drivecopy (Linux or Windows) roughly 90-180 minutes.
This is fast and with success executable with the commands
'dd if=/dev/SOURCE | gzip > BACKUP_PATH/image.gz' and
'gzip -dc /BACKUP_PATH/image.gz | dd of=/dev/SOURCE' for recovery.
The same is when you pack or unpack a lot of folders and data with 'tar[options][archiv][data]'.

Here you can't need 'sudo', sudo has a time stamp with a time of validity of some minutes. You need here more time!
So is the danger, that the copy or recovery performance with 'sudo su' breaks. Only using 'su' you get unlimited time for such operations with success.

[Gunnar Hjalmarsson (gunnarhj)]

This type of discussion does not fit well on a bug report, especially not a bug against the documentation... I would recommend you to bring up the topic on the ubuntu-devel-discuss mailing list.

https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss