I have TX1 and there are two users Ubuntu and Nvidia. What are the deference between them?? And if I install JetPack using Ubuntu user, does it mean that I can use Tx1 from Nvidia user ? And is the Jetpack will be in Nvidia user as well??
In the earlier software flash there was only user “ubuntu” by default. Then there was both “ubuntu” and “nvidia”. Eventually there was just “
ubuntu nvidia” I think? But then California law made it illegal to ship with default user name/pass combinations, and it because “whatever the user creates at first boot”.
Every user has a numeric user ID, plus a numeric group ID. The actual user name/group is just an alias people see as a convenience, and it is the numeric ID which is used for actual access privilege. The default is that a group name for a regular user will be the same as the user name. So for example, unless something is done to prevent it, creating a user named “ubuntu” also creates group “ubuntu”, and only that user is a member of the group. Creating user “nvidia” would also create group “nvidia”, and only user “nvidia” is a member of group “nvidia”. However, the system admin can assign “supplemental” groups, and thus the user might have a primary group, but also be a member of some other group.
Typically end users start with a numeric ID of 1000. The next user will have ID 1001. The user after that ID 1002. So on (unless the command to create the user specifies a different numeric ID).
If a regular user is a member of the “sudo” group, then you could say the user is an “admin” because it is “admin” which is allowed to use the “sudo” command. The master of all groups is “root”, and root is user ID 0. When you use “sudo” you are momentarily becoming user ID 0.
The ID of regular users start at 1000 and goes up. The ID of system accounts are 999 or below.
Users of accounts “ubuntu” and “nvidia” are both members of “sudo”, so they are the same in most respects. However, in the past it was the Ubuntu software which used “ubuntu” as a default admin name.
Neither “ubuntu” nor “nvidia” had any difference so far as privilege goes.
When NVIDIA installs some software part will go in the user’s home directory, for example, “~/nvidia”. When tutorials are shown, if you use the wrong user, then the content might not be there. You could of course set up any user with that software.
For terminology, JetPack does not actually to the Jetson. There does happen to be a package on newer releases called “nvidia-jetpack”, but this is not a program. It’s simply some metadata about available packages, which happen to be packages JetPack knows about. JetPack is a GUI front end for other software, and installs on the host PC. After adding some network utilities and rearrange some, this was changed to SDK Manager. You can more or less use the names SDKM and JetPack interchangeably.
None of these packages or support are specific to an account name on the Jetson. On the PC any user (other than root) can use JetPack/SDKM, and this would create some content in your home directory (which has alias “
~”). As long as your user is a member of group “sudo”, then JetPack/SDKM won’t care what the name or numeric ID are. JetPack is not installed to a user, it is installed to the operating system.
You can examine what groups your user is a member of. If your user name is “nvidia”, then this would tell you all of that user’s groups:
grep 'nvidia' /etc/group
There are actual commands to answer this without grep of the “
group” file, or to change or add groups, for example, the command “
If your desktop PC account from which you normally work has a given numeric ID (which is probably 1000 if it is the first user created), then it is easier to work on an account of the same numeric ID on the Jetson. When you copy files across Jetson and host PC via ssh, unless you are root, then you cannot force different numeric IDs to be preserved. This won’t matter unless you are backing up software. Having ownership change during a backup is a big “don’t do that”. Even if you back up using root/sudo you would need to specify to not alter numeric IDs during any backup operation.
FYI, when a Jetson is flashed, it is “Linux for Tegra” (“L4T”) which is flashed, not JetPack. JetPack is not the actual flash software. “L4T” is itself just Ubuntu after adding NVIDIA drivers.