zfsbootmenu VS ramroot

We use a couple nice home-grown functions in ZFSBootMenu to help debug things. We have a zdebug logging function that's peppered liberally throughout the code base - https://github.com/zbm-dev/zfsbootmenu/blob/master/zfsbootme...

Hitting ctrl-t on our main menu will, when booting with debug logging enabled, show a screen like this: https://imgur.com/Ge75zkP

We also have a flamegraph profiling mechanism that can be enabled with https://github.com/zbm-dev/zfsbootmenu/blob/master/zfsbootme... . That will dump data to a serial port, which when re-assembled, can be used to produce a graph like https://raw.githubusercontent.com/zbm-dev/zfsbootmenu/master...

Bash is suprisingly flexible.

A lot of what's in the Pure Bash Bible is horrifically slow. Many of those things are substantially faster, even when paying the cost of starting a new process, when you use an external and commonly available tool. I wrote a bash performance profiler that outputs data in a format that flamegraph.pl recognizes - it really helped identify where we could improve the performance of ZFSBootMenu.

https://github.com/zbm-dev/zfsbootmenu/releases/tag/v1.12.0

Don't fall in the trap of thinking things have to be written entirely in bash; it's okay to use other tools to help fill in the gaps.

If instead of "opensuse" you're asking for bootloader as grub can't boot from zfs, then, like i metnioned, i don't use grub2, i uninstalled it, instead i'm using https://github.com/zbm-dev/zfsbootmenu

I thought the following was supposed to fix this issue: https://github.com/zbm-dev/zfsbootmenu/commit/84da18e64ebcc0c483e7b2c7d3972f7d91784e63

All release assets, including EFI executables and kernel/initramfs pairs, are signed with signify, which provides a simple method for verifying that the contents of the file are as this project intended. Once you've installed signify (that's left as an exercise, although Void Linux provides the signify package for this purpose), just download the desired assets from the ZFSBootMenu release page, download the file sha256.sig alongside it, and run:

I think the consensus is that you probably shouldn't be installing a ZFS on root using the native installer anymore. They aren't really maintaining the packages that make that work. Instead the suggestion is to go the zfsbootmenu route of installing.

Glad to hear that everything is working for you! I've opened a PR that adds a warning about this condition - it should likely make it into 2.2.0.

You can install following instructions at https://openzfs.github.io/openzfs-docs/Getting%20Started/Debian/Debian%20Bullseye%20Root%20on%20ZFS.html which I've automated with https://github.com/HankB/Linux_ZFS_Root/tree/master/Debian. For scripting, you should also look at https://github.com/zbm-dev/zfsbootmenu. I'd probably go that way if I were starting from scratch.

ZBM provides an amazingly useful script in it's wiki here. This runs when a new kernel is updated by xbps and it snapshots your system before the kernel is installed. This creates a boot environment, and via the magic of ZFS boot environments, allows you to rollback any kernel update to a known, working configuration.

* https://docs.oracle.com/cd/E86824_01/html/E54764/beadm-1m.ht...

> A ZFS boot environment is a bootable clone of the datasets needed to boot the operating system. Creating a BE before performing an upgrade provides a low-cost safeguard: if there is a problem with the update, the system can be rebooted back to the point in time before the upgrade.

* https://klarasystems.com/articles/managing-boot-environments...

Or perhaps:

> In essence, ZFSBootMenu is a small, self-contained Linux system that knows how to find other Linux kernels and initramfs images within ZFS filesystems. When a suitable kernel and initramfs are identified (either through an automatic process or direct user selection), ZFSBootMenu launches that kernel using the kexec command.

* https://github.com/zbm-dev/zfsbootmenu

Now I can use ramroot and run the whole OS on RAM.

Anyway, I wrote and maintain a guide to make this setup: https://mags.zone/help/arch-usb.html. I also made a package to optionally load everything to RAM during boot: https://github.com/arcmags/ramroot.

I wrote a tool to load root entirely into RAM on Arch. It checks available RAM and prompts on boot.

You could also use the Arch Linux guide above and install Arch Linux on the USB drive, making sure the boot and root partition sizes are less than the amount of ram in the machine you are booting on. Then install ramroot which will load up your system into ram on boot. This will mean the system runs off ram and not USB. If you need to make changes, install applications or update, you could boot it normally so it runs off USB as any changes won't be saved if it is booted into ram. If your home folder is on another partition on the USB, I don't think that is loaded into ram on boot so you can still save files to it and any personalisations should also be kept between boots.