Re: Installer: GUIX_IMAGE as /dev/sda on some hardware?
Hello! Giovanni Biscuolo skribis: > But wait! There's the /dev/disk/by-id/ tree, I did not notice it until > now! :-) > > That's the solution: > > > (bootloader > (bootloader-configuration > (bootloader grub-bootloader) > (target "/dev/disk/by-id/scsi-3600508b1001c75a3bebb04b23d19e249") > (keyboard-layout keyboard-layout))) > > I did not test this but it smells like running, if Guix devels agree I > think Installer should adopt /dev/disk/by-id by default, sorry I'm not > able to propose a patch for this Ideally, we’d use an actual UUID object (or a string?) here rather than this Linux/udev-specific idiom. So it would look like: (bootloader-configuration ;; … (target (uuid …))) Would that work? I believe using Guile-Parted we could map it back to a /dev name. WDYT? Ludo’.
Re: Installer: GUIX_IMAGE as /dev/sda on some hardware?
[Part two, having made my train connection with 8 seconds to spare.] Giovanni Biscuolo wrote: But wait! There's the /dev/disk/by-id/ tree, I did not notice it until now! :-) Yes! That's what I meant! Thank you. I'll be sure to use the udev terminology for this in future, it's confusing enough as it is. Thanks, T G-R signature.asc Description: PGP signature
Re: Installer: GUIX_IMAGE as /dev/sda on some hardware?
Giovanni, Giovanni Biscuolo wrote: /dev/xdyN names have never been safe to use in this way I'm not talking about partitions ;-) Neither was I. Force o' habit. May your partitions never be in random order. According my faulty memory (I cannot reproduce it now) /dev/sd is what the Installer writes in the bootloader section of config.scm: --8<---cut here---start->8--- (bootloader (bootloader-configuration (bootloader grub-bootloader) (target "/dev/sda") (keyboard-layout keyboard-layout))) I didn't realise that our *installer* did this… It shouldn't. Thanks for noting this. So it's pure coincidence that grub-install on /dev/sda succeedes on the whole set of machines users are installing via USB media? :-O ‘Pure coincidence’ is too loaded. It almost always works! But your original question already illustrates how ‘almost always works’ leads to false inductions of ‘should work’. The odds may be hugely in your favour, but why gamble at all? you've discovered, they aren't to be relied on, and you should use labels or UUIDs instead. Labels and UUIDs are for volumes, not for the whole disk ;-) …? I must not be using the right terminology, but each drive has a ‘unique identifier’, and a human-readable label (if that human likes numbers, a lot) that isn't unique. ‘ID’ & ‘name’, then, fine, whatever we call it, my point remains :-P Kind regards, T G-R signature.asc Description: PGP signature
Re: Installer: GUIX_IMAGE as /dev/sda on some hardware?
Giovanni Biscuolo wrote: This is **very** important when installing grub, in fact grub installation failed when instantiating my config.scm on the HP ProLiant simply because it was on /dev/sda pointing to the USB media; /dev/xdyN names have never been safe to use in this way, though. I guess they're fine (at your own risk…) as short identifiers during a single CLI session, but not across reboots. It just often *happens* to work on most machines, which as we all know, is the most dangerous kind of working. 3. how is the USB media "relocated" to the last /dev/sd? device by the installer? It's… not? Dev nodes & names are doled out by the kernel. As you've discovered, they aren't to be relied on, and you should use labels or UUIDs instead. Even if we'd pretend differently in the installer, for example through artificially delayed probing for usb_storage devices, things would still break when that lie would be exposed by adding a new SATA drive, or when using a different (rescue) distro, or… 1. has anyone observed a similar issue? 2. what could have caused it? I used to own a system that scanned drives in a different order depending on whether or not a USB keyboard was attached. It was intended as a headless system; great fun debugging that! I once corrupted a drive (luckily part of a RAID-1 array, but it was still stupid of me) because the rescue CD scanned drives in a different order than the distro I was used to. My first SATA motherboard enumerated drives differently between cold and warm boots — but only sometimes. I think it had something to do with spin-up times. I could go on. I often do. Sorry. Hoping to have scared you into using UUIDs, T G-R signature.asc Description: PGP signature
Installer: GUIX_IMAGE as /dev/sda on some hardware?
Hello Guix! I cannot reproduce this anymore since the machine I used is no more under my physical control and is in production... anyway I'm sure on a HP ProLiant DL380p Gen8 the installer image (1.0.0 version) [1] listed the USB media as /dev/sda while I've always observed (and reproducing now on a testing machine) that it's listed as **the last** /dev/sd? device in the list This is **very** important when installing grub, in fact grub installation failed when instantiating my config.scm on the HP ProLiant simply because it was on /dev/sda pointing to the USB media; I had to manually install grub on /dev/sdb to complete the install A couple of questions: 1. has anyone observed a similar issue? 2. what could have caused it? 3. how is the USB media "relocated" to the last /dev/sd? device by the installer? Happy hacking! Gio'. [1] the only custom thing I made was adding "vga=791" and removing "quiet" from the kernel arguments -- Giovanni Biscuolo Xelera IT Infrastructures signature.asc Description: PGP signature
