thank you for your response. I don't have a serial cable at the moment, so for now I think I'll leave it booting off nand Also it's purpose is a backup server and the backup /dev/md0 are USB RAID1 drives, so that's ok, I think NAND won't just fail randomly in the foreseeable future, I hope at least
I would also need to build uInitrd presumably for the USB RAID1 boot to work, I tried to execute:
mdadm --examine --scan >> /etc/mdadm/mdadm.conf => this populated the array definition correctly
However, when I then ran dpkg-reconfigure mdadm, specified that all the arrays are needed for the root filesystem, no initramfs was generated in /boot. Can you please hint on how I should generate compatible uInitrd with this kernel, and does the boot loader support reading uInitrd into memory from NAND? I suppose it should since it can read & load the kernel.
As for the swapon issue, I tried dphys-swapfile, that did not work, and gave the error message I posted previously. I now tried direct swapon as root, and it still failed:
root@backups-ci20:~# mkswap /var/swap
mkswap: /var/swap: warning: wiping old swap signature.
Setting up swapspace version 1, size = 1048572 KiB
no label, UUID=8c312388-b8b4-4972-8c3a-aa3d8b83fb36
root@backups-ci20:~# swapon /var/swap
swapon: /var/swap: swapon failed: Invalid argument
Here's how my /etc/fstab looks like, I don't have a swap line there:
root@backups-ci20:~# cat /etc/fstab
ubi0:boot /boot ubifs defaults,rw 0 0
/dev/md0 /backups ext4 defaults,rw 0 0
# a swapfile is not a swap partition, no line here
# use dphys-swapfile swap[on|off] for that
Also the permissions are correct on the swapfile:
root@backups-ci20:~# ll /var/swap
-rw------- 1 root root 1073741824 Feb 14 18:21 /var/swap
Any other help is welcome, thank you!