[SOLVED] Arch Netboot / recovery tool / partition

Cvlc · 2021-12-20 01:22:48

Hi

Is the small netboot image usable as a recovery tool in the ESP, instead of writing an ISO to a USB key ?

I've looked at :

* https://wiki.archlinux.org/title/Netboot
* https://wiki.archlinux.org/title/Archboot
* https://wiki.archlinux.org/title/System … plications
* https://wiki.archlinux.org/title/System … rml_on_ESP
* https://wiki.archlinux.org/title/REFInd#Tools

I feel like Archboot is more what I'm looking for. I've managed to boot the netboot image from /esp/arch-netboot/ipxe.efi with Systemd-boot, but t doesn't look like I could do any recovery from that if needed, I get kernel panics, no network, etc...

Is the Archboot image the smallest working rescue environment I can get ? If this is the case, how is this generally done, on a large ESP or on an XBOOTLDR partition ?

Thanks !

Last edited by Cvlc (2022-08-07 21:46:56)

Head_on_a_Stick · 2021-12-20 07:37:23

Archboot seems better than netboot because the latter needs a working internet connection and hammers the Arch mirrors every time you use it.

No need to store it on the ESP or XBOOTLDR partition though, GRUB can load it from a system partition just fine. Reference: https://wiki.archlinux.org/title/Archbo … boot_modes

Cvlc · 2021-12-20 09:37:31

Thanks for your answer !

I forgot to mention, my root is encrypted and I have no grub, just systemd-boot launching efi images... which is why I'm trying to put it into the ESP.

That's why I loved the idea of the netboot because it's really small, I'm not supposed to use it often (never ? ) and if I ever need it, it's automatically the latest image...

Head_on_a_Stick · 2021-12-20 10:04:44

systemd-boot is only capable of starting EFI applications so you would have to write one yourself that loads a filesystem driver, unlocks the root partition, mounts the ISO image and loads the kernel & initramfs. Or change to GRUB.

Cvlc · 2021-12-20 13:49:51

You mean for the netboot image ? Because Archboot should work with systemd-boot, shouldn't it ?

If nobody's done it then I suppose that it's not the way to go.

I'm surprised it's not a more commonly addressed question, seems like a very useful thing to have some kind of small recovery partition or rescue image instead of always keeping an arch usb around in case.

Last edited by Cvlc (2021-12-20 13:52:56)

Head_on_a_Stick · 2021-12-20 14:03:21

Cvlc wrote:

Because Archboot should work with systemd-boot, shouldn't it ?

Not according to the link I provided in post #2.

Cvlc · 2021-12-20 23:56:54

I'll try it out when I'm back in a week or so, because

For Rescue booting add an entry to your bootloader pointing to the kernel and initrds, and add rootfstype=ramfs to your kernel cmdline.

This part of the Archboot wiki article seems to suggest it might be possible.
Well anyway for now it's too large for my ESP.

Cvlc · 2021-12-21 00:04:12

Found this : https://netboot.xyz/downloads/

Has .efi images. I need to read further though

Edit

Found this from two years ago where you answered but it's a dead end even though you said there would be "no surrender"

Just jotting it down because I'm away and cannot test anything, and it looks exactly like the errors I got

Last edited by Cvlc (2021-12-21 00:23:29)

Head_on_a_Stick · 2021-12-21 12:56:33

Cvlc wrote:

Found this from two years ago where you answered but it's a dead end even though you said there would be "no surrender"

Yeah, I'm full of shit sometimes

So your router only supplies IPv6? That seems a bit strange. Anyway I really don't have any idea about netbooting so you'll have to wait for somebody who does. Sorry.

Cvlc · 2021-12-21 14:19:12

Head_on_a_Stick wrote:

So your router only supplies IPv6? That seems a bit strange.

No the old thread wasn't from me... Juat found it there.

From netboot wiki page :

The ipxe.efi image can be used to launch Arch Linux netboot in UEFI mode. Only 64-bit UEFI is supported. The ipxe.efi image can be added as a boot option via efibootmgr, launched from a boot manager, like systemd-boot or rEFInd, or directly from the UEFI shell.

That gives some hope. I'll tey again soon and report back.

kermit63 · 2021-12-22 06:34:16

How many devices do you have that can independently download ISOs and create a bootable USB stick from it?

If you only have one such device, then you can't totally do away with having a bootable USB stick, even if you get ipxe working on your computer. Some processes like upgrading the UEFI firmware of you computer will wipe out the efi entries, thus leaving you with a non-bootable system. Same situation if you replace your motherboard. Hard drive crashes can leave your efi partition inaccessible.

In addition, arch ipxe servers aren't entirely reliable. I have a working ipxe entry on my computer for at least 5 years. Once in a while (probably every 6 months on average) I'll check if the ipxe efi entry works. I'll boot into it, wait until the network gets configured and connect to the ipxe servers and cancel just when it starts downloading. Most of the time if works (say 70%). However, there were long stretches were the same entry won't work due to some error on the server side.

Some of the issues above applies to archboot as well. Although I don't use archboot, per se, I have a custom grub entry that can boot a customized arch iso on my drive. This is my go-to option for doing rescue/partitioning work. However, those situations I mentioned can also prevent me from accessing the custom grub entry, thus necessitating the use of a bootable USB stick.

-----

On those rare occasions when I let the ipxe process finish downloading, it works pretty well and has the exact same functionality as if booting from a bootable USB stick.

Last edited by kermit63 (2021-12-22 06:38:57)

Cvlc · 2021-12-22 09:09:37

kermit63 wrote:

How many devices do you have that can independently download ISOs and create a bootable USB stick from it?.

I do have a working Raspberry pi as well, for the cases you nentioned which indeed I hadn't considered. Could write a USB stick from there in case the efi entries are borked or the SSD fails. It's a laptop though, so if the disk is dead I guess i'll have time to get a new USB iso before I get a new drive :)

But the netboot could work well on other cases like me accidently ruining some config or to roll back to a btrfs snapshot after a bad update..

I think the netboot iso suggested different mirrors when I tried it, tried two if I remember well which got me the same errors.

Last edited by Cvlc (2021-12-22 09:10:21)

Cvlc · 2022-01-03 18:34:55

Ok, so I can confirm that the Netboot image boots properly with a systemd boot entry like :

title   Arch Netboot
efi     /EFI/arch_netboot/ipxe-arch.efi

I have a problem setting up an internet connection but I'll open a different thread for that.

Only thing strange is I cannot "quit". "reboot" does nothing, and quit throws a kernel panic

Last edited by Cvlc (2022-01-03 18:42:21)

Arch Linux

#1 2021-12-20 01:22:48

[SOLVED] Arch Netboot / recovery tool / partition

#2 2021-12-20 07:37:23

Re: [SOLVED] Arch Netboot / recovery tool / partition

#3 2021-12-20 09:37:31

Re: [SOLVED] Arch Netboot / recovery tool / partition

#4 2021-12-20 10:04:44

Re: [SOLVED] Arch Netboot / recovery tool / partition

#5 2021-12-20 13:49:51

Re: [SOLVED] Arch Netboot / recovery tool / partition

#6 2021-12-20 14:03:21

Re: [SOLVED] Arch Netboot / recovery tool / partition

#7 2021-12-20 23:56:54

Re: [SOLVED] Arch Netboot / recovery tool / partition

#8 2021-12-21 00:04:12

Re: [SOLVED] Arch Netboot / recovery tool / partition

#9 2021-12-21 12:56:33

Re: [SOLVED] Arch Netboot / recovery tool / partition

#10 2021-12-21 14:19:12

Re: [SOLVED] Arch Netboot / recovery tool / partition

#11 2021-12-22 06:34:16

Re: [SOLVED] Arch Netboot / recovery tool / partition

#12 2021-12-22 09:09:37

Re: [SOLVED] Arch Netboot / recovery tool / partition

#13 2022-01-03 18:34:55

Re: [SOLVED] Arch Netboot / recovery tool / partition

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