This update is, supposedly, valid fort the Jetson Nano. However, I have been told that I cannot install/flash things with the SDK if I’m using external media, (which I am), rather I have to use the flash.sh script.
How do I go about installing an operating system update using flash.sh? All the examples I’ve seen are only for the other boards - Orion, Tegra, Xavier, etc. - but not the Nano.
How do I install operating system development features? (CUDA and the other development tools.)
JetPack is a front end for the installer and does not go on the Jetson. L4T R32.7.4 is the actual content being flashed, and that is Ubuntu plus NVIDIA drivers. The part which is less obvious is that any SD card dev kit puts the boot and BIOS equivalent in QSPI memory. It is the QSPI flash which updates the Nano itself to be able to boot R32.7.4. The SD card itself can be taken from the pre-canned images. In the case of an initrd flash for external media this still updates QSPI, although it points at different media and also updates an initial ram disk to make drivers available to the Linux kernel before pivoting over to the actual rootfs external media.
So you wouldn’t use flash.sh, you’d use the initrd flash, which is almost the same as flash.sh. You have to go to the “Linux_for_Tegra/tools/kernel/flash/” directory to find l4t_initrd_flash.sh. There are README files there.
Normally the optional packages are installed vi JetPack/SDK Manager to a fully booted Jetson over ssh. If you install on command line using the initrd flash, and complete first boot account setup, then ssh should become available. You can then start sdkmanager (sometimes with option --archived-versions that might not otherwise be visible), and uncheck everything such as flash, and then recheck just those items you want. Because flash is not set only a fully booted Jetson will work, and it is safe against flash (also it can’t flash without being in recovery mode). It often is not obvious that JetPack/SDK Manager installs those extra packages to a fully booted Jetson (it is a convenience that the Jetson self-reboots after flash, but nothing marks it as obviously no longer being in recovery mode).