Dual Boot Nvidia Xavier

I’m trying to dual boot an AGX Xavier on a Rogue carrier board to boot from the SD card when it’s inserted but if the SD card is missing to have it mount a root file system from another source(NFS/EMMC).
I can flash the EMMC to successfully boot from the SD card or boot NFS/EMMC but only one or the other.

I’m not sure how to proceed such that I mount the SD card as the root file system only if it’s present, I’m presuming I’ll need to use bootloader commands?

I don’t think this is a unique need but haven’t had much luck in the way of finding resources.


Which jetpack version is in use here?

I’m using R32 (release), Revision 7.2, which I understand to be JetPack4.6.2

Just to update my question as I’ve looked around and understand our requirements better, what I’m hoping to accomplish is to mount a rootfs as either the SD card if it’s present and try to connect over NFS if it isn’t - or vice versa.

There was a version requirement change, so the board will now be using R35.1

I’ve tried working with extlinux.conf unsuccessfully (don’t get a menu) as well as trying to boot with the SD card as the primary boot method but haven’t had luck down either avenue yet