FYI, it has been a long time since there was a default name/password. Some time back California law changed, and this instead turned into a first boot account setup.
If you were to try to work with any flash software, then you’d want to work with the same release of L4T which the SD card was designed to match. On a host PC you can use “
head -n 1 /etc/nv_tegra_release” to see that release. JetPack/SDK Manager is a front end to flash software, and L4T is what actually gets flashed. L4T, in turn, is just Ubuntu plus NVIDIA drivers. Both the flash software and the image going on the rootfs (in this case SD card) matter even on an SD card model since embedded systems don’t have a BIOS (flash is not just the rootfs and bootloader, it is also the equivalent of flashing the BIOS, but done in software without a hardware BIOS). For an SD card model there is embedded QSPI memory for the non-rootfs content (which is what is flashed) as well as the rootfs (in this case on SD card, which can be worked with separately). To find which software to use when matching that release go to the L4T shown in this URL:
You will need an Ubuntu 18.04 host PC if you want to use the flash software. VMs are not officially supported and tend to fail if USB is not set up correctly, but can work. In your case it might not matter if all you want to do is set up for flashing a rootfs (which is really just copy to the SD card, you don’t need the Nano connected for that, nor would the Nano be flashed). If the L4T release does not change, then there is no need to flash anything on the Nano.
There isn’t any “cracking” a password, all you can do is install or flash a new image which has not yet completed first boot setup. However, installing that software produces this directory, which is where most command line work would be performed from (you’d use the JetPack/SDK Manager release matching the L4T release…more on JetPack below):
The L4T page will lead you to the JetPack/SDKM page, but you can use a more recent JetPack/SDKM, and start it like this to make available earlier releases from the newer JetPack/SDKM:
(JetPack versions available here)
If you have installed the flash software, then JetPack/SDKM will have installed and prepared “
Linux_for_Tegra/rootfs/”. You can see if there is content in “
Linux_for_Tegra/rootfs/”. When a default image is generated for the rootfs it is almost an exact copy of that content. It is an entire operating system install.
There is a tool located at “
Linux_for_Tegra/tools/”. That tools is for people who want to do the equivalent of running first boot account setup prior to ever flashing. If that tool has been used, then the default image will have the chosen details from its very first boot, including login name and password. You can, from “
Linux_for_Tegra/”, do this for setting that up:
# Follow the instructions. "rootfs/" will be set up accordingly.
There are several choices from here. I’ll suggest:
- You could create an image based on this, and use it to generate an SD card image.
- You would then copy (using
sudo) files related to login name and password of “
rootfs/etc/” over the same files on the SD card image.
- Files in “
rootfs/etc/” on the host PC) which would be relevant (I don’t know if they are all required, but it is best to copy all of them):
You won’t find any information on actually cracking a password. All you can get are variations on backing up the original and flashing with a new user setup with physical access. All of the above is a combination of advice on backing up and flashing.
Do note that in JetPack/SDKM you can uncheck items you won’t use. Uncheck everything other than Jetson install. You can also check to install but not perform the flash to get the content.