eselarm

it all depends on what your plan is what the device should do; I have a R6C for about 18 months now and bought it as an alternative/better more integrated alternative for existing RPi4 (and also RPi5 that still has no M.2 socket). I see many people on for example RPi forum who want to create some router thing, so they buy HATs and USB stuff for an RPi, but this NanoPi series has even WRT preinstalled. I removed it as I wanted generic server box (virtual machines host mainly). I do not really need the 2x RJ45 currenlty, but the metal case is great.  Is simple passive cooling and insect/animal proof. It is mainly bootloader and kernel (and DTB/overlays) that matter. The userspace can be taken from elsewhere if you know how to. I currently use the R6C as desktop as well in another cooler room (summer hot here). EDK2-UEFI v1.1 bootloader, Armbian edge 6.16-rc3 kernel, Opensuse Tumbleweed for Btrfs rootfs to drive a DVI monitor KDE plasma 6.4.x. It means various Rockchips HW blocks do not work like NPU and video codecs HW accel block, but that is a choice. If you need those, use vendor kernel and see what exctly you need/want. The 2x RJ45 might be a chalenge, see maybe also: 
 

check those files
/usr/lib/systemd/system/armbian-resize-filesystem.service
/usr/lib/armbian/armbian-resize-filesystem
 

OK, as I thought, not enough 'headroom'
 
rock5b:/local/ssdata/nocow # btrfs inspect-internal list-chunks 2 btrfs inspect-internal list-chunks 2 Devid PNumber Type/profile PStart Length PEnd LNumber LStart Usage% ----- ------- ----------------- -------- --------- -------- ------- -------- ------ 1 1 System/single 1.00MiB 4.00MiB 5.00MiB 4 2.30GiB 0.39 1 2 Metadata/single 5.00MiB 8.00MiB 13.00MiB 1 5.00MiB 35.74 1 3 Data/single 13.00MiB 8.00MiB 21.00MiB 2 13.00MiB 100.00 1 4 Data/single 21.00MiB 1.00GiB 1.02GiB 3 21.00MiB 53.20 1 5 Metadata/single 1.02GiB 208.00MiB 1.22GiB 5 2.31GiB 23.51 1 6 Data/single 1.22GiB 512.00MiB 1.72GiB 6 2.51GiB 84.35 1 7 Data/single 1.72GiB 512.00MiB 2.22GiB 7 3.01GiB 86.48 1 8 Metadata/single 2.22GiB 256.00MiB 2.47GiB 8 3.51GiB 33.67 1 9 Metadata/single 2.47GiB 256.00MiB 2.72GiB 9 3.76GiB 14.43 1 10 Data/single 2.72GiB 1.00GiB 3.72GiB 10 4.01GiB 83.88 1 11 Data/single 3.72GiB 1.00GiB 4.72GiB 11 5.01GiB 97.23 1 12 Data/single 4.72GiB 1.00GiB 5.72GiB 12 6.01GiB 55.02 1 13 Data/single 5.72GiB 1.00GiB 6.72GiB 13 7.01GiB 85.21 1 14 Data/single 6.72GiB 1.00GiB 7.72GiB 14 8.01GiB 58.04 1 15 Data/single 7.72GiB 1.00GiB 8.72GiB 15 9.01GiB 82.03 1 16 Data/single 8.72GiB 1.00GiB 9.72GiB 16 10.01GiB 28.15 1 17 Metadata/single 9.72GiB 256.00MiB 9.97GiB 17 11.01GiB 10.30 1 18 Data/single 9.97GiB 1.00GiB 10.97GiB 18 11.26GiB 99.83 1 19 Metadata/single 10.97GiB 256.00MiB 11.22GiB 19 12.26GiB 0.58 1 20 Metadata/single 11.22GiB 256.00MiB 11.47GiB 20 12.51GiB 5.22 1 21 Metadata/single 11.47GiB 256.00MiB 11.72GiB 21 12.76GiB 0.49 1 22 Metadata/single 11.72GiB 256.00MiB 11.97GiB 22 13.01GiB 0.27 1 23 Metadata/single 11.97GiB 27.00MiB 12.00GiB 23 13.26GiB 0.06 Then doing various balance actions, then again replace action, see result below:
[334356.515225] [ T207531] BTRFS info (device loop0p2): balance: start -mlimit=3 -slimit=3 [334356.516261] [ T207531] BTRFS info (device loop0p2): relocating block group 14236516352 flags metadata [334356.608520] [ T207531] BTRFS info (device loop0p2): found 1 extents, stage: move data extents [334356.655369] [ T207531] BTRFS info (device loop0p2): relocating block group 13968080896 flags metadata [334356.882397] [ T207531] BTRFS info (device loop0p2): found 44 extents, stage: move data extents [334356.974962] [ T207531] BTRFS info (device loop0p2): relocating block group 13699645440 flags metadata [334357.145812] [ T207531] BTRFS info (device loop0p2): found 77 extents, stage: move data extents [334357.223337] [ T207531] BTRFS info (device loop0p2): balance: ended with status: 0 [334402.346978] [ T207580] BTRFS info (device loop0p2): balance: start -mlimit=6 -slimit=6 [334402.347912] [ T207580] BTRFS info (device loop0p2): relocating block group 13431209984 flags metadata [334403.120645] [ T207580] BTRFS info (device loop0p2): found 841 extents, stage: move data extents [334403.372968] [ T207580] BTRFS info (device loop0p2): relocating block group 13162774528 flags metadata [334403.613848] [ T207580] BTRFS info (device loop0p2): found 94 extents, stage: move data extents [334403.743610] [ T207580] BTRFS info (device loop0p2): relocating block group 11820597248 flags metadata [334404.526435] [ T207580] BTRFS info (device loop0p2): found 1666 extents, stage: move data extents [334404.798554] [ T207580] BTRFS info (device loop0p2): relocating block group 4035969024 flags metadata [334406.059117] [ T207580] BTRFS info (device loop0p2): found 2363 extents, stage: move data extents [334406.374011] [ T207580] BTRFS info (device loop0p2): relocating block group 3767533568 flags metadata [334407.879438] [ T207580] BTRFS info (device loop0p2): found 5433 extents, stage: move data extents [334408.284506] [ T207580] BTRFS info (device loop0p2): relocating block group 2475687936 flags metadata [334413.884083] [ T207580] BTRFS info (device loop0p2): found 9463 extents, stage: move data extents [334414.690177] [ T207580] BTRFS info (device loop0p2): balance: ended with status: 0 [334530.694011] [ T207693] BTRFS info (device loop0p2): balance: start -dlimit=2 [334530.694839] [ T207693] BTRFS info (device loop0p2): relocating block group 12089032704 flags data [334534.205097] [ T207693] BTRFS info (device loop0p2): found 1897 extents, stage: move data extents [334534.491352] [ T207693] BTRFS info (device loop0p2): found 1897 extents, stage: update data pointers [334534.625126] [ T207693] BTRFS info (device loop0p2): relocating block group 10746855424 flags data [334536.605759] [ T207693] BTRFS info (device loop0p2): found 16316 extents, stage: move data extents [334537.056028] [ T207693] BTRFS info (device loop0p2): found 16316 extents, stage: update data pointers [334537.361629] [ T207693] BTRFS info (device loop0p2): balance: ended with status: 0 [334614.951029] [ T207803] BTRFS info (device loop0p2): dev_replace from /dev/loop0p2 (devid 1) to /dev/loop1p2 started [334654.572435] [ T207803] BTRFS info (device loop0p2): dev_replace from /dev/loop0p2 (devid 1) to /dev/loop1p2 finished So  I would need to do the same with vendor kernel on same images, I made exact copies, so can be done, however starting with vendor kernel requires system reboot (and other bootloader), so not sure when I can do this. 

You could run:
sudo apt list | grep linux-image
Besides the vanilla Debian/Ubuntu ones, there are Armbian ones: vendor, current, edge
 
In your case your installed U-Boot might be incompatible with kernel 6.1.84, I had that for my Rock3A, I installed mainline U-Boot.
 
If you want all kernels, use http://beta.armbian.com in /etc/apt/sources.list.d/armbian.list

Or build yourself from source. The Armbian build runs fine on my NanoPi-R6C Armbian Bookworm

I found the reason for the crash:  the 6.1.84-vendor-rk35xx doesn't work together with the 2024.10 mainline U-boot.
 
Earlier the SPI-flash was empty and the Rock3a booted from SD-card, a U-boot version from 2017 (Armbian_24.11.1_Rock-3a_noble_current_6.6.62-kisak.img.xz). I put that image in 'beta' mode so I got the 6.1.84-vendor-rk35xx (+ rock-3a-sata.dtbo). That all still worked.
I then put the 2024.10 mainline U-boot in SPI and wiped the sector range 34-32767 from the SD-card. Then I discovered that the 6.1.84-vendor-rk35xx always crashed, independent of SATA modules etc.
 
I now disabled the SPI and took sector range 34-32767 from the official Radxa image (rock-3a_debian_bullseye_cli_b25.img.xz) and put that on the SD-card with the Armbian Noble (latest beta channel trunk.201) and rebooted. That does not crash and works same as with 6.12.6-edge-rockchip64 that I used before the reboot to write the sector range 34-32767.
Version is:  latest-2023.07.02-3-b1eb2bde-gb1eb2bde (Aug 29 2023 - 10:43:04 +0000) 
 
So I guess I need to look at differences in uboot configs and likely also uboot sources.
 
The other thing is that If I want to be able to boot from a single SATA device with the Rockchip on-chip SATA, the uboot In the SPI-needs to default to SATA for M.2 E-key connector and not the default PCIe-2x1.
Or wait till I got an extra NVME to put in the M.2 M-key  connector and load rock-3a-sata.dtbo after uboot together with kernel. That is preferred I think looking at possible future use-cases.
 

I do not use quotas, so the fix for this issue is: https://github.com/openSUSE/snapper/issues/894#issuecomment-2054220427