netboot's partman sees only disk as /dev/sdb (SCSI2)

[Thierry Carrez]

Not sure if it's a bug or against which package this should be filed, but here is for tracking purposes:

On netboot installs of Lucid beta2, the first disk is shown by partman as being /dev/sdb (SCSI2).

I used to have working preseeds with:
d-i partman-auto/disk string /dev/sda
d-i grub-installer/bootdev string /dev/sda

Now they need to have:
d-i partman-auto/disk string /dev/sdb
d-i grub-installer/bootdev string /dev/sda

Note that this seems to be netboot-specific, partman for ISO installs on the same machine still sees /dev/sda (SCSI1).

I know we shouldn't mind the changes in device names, so if that's by design, please feel free to close this.

[Dustin Kirkland  (kirkland)]

I'm confirming, as I saw the same thing in my preseed UEC installs. I discussed this in IRC with cjwatson:

Mar 30 06:58:23 <kirkland> cjwatson: okay, I'm past the previous iscsi question; but my old preseed file isn't getting me past partitioning automatically any more
Mar 30 06:58:38 <cjwatson> what question is it stopping at?
Mar 30 06:59:22 <kirkland> http://pastebin.ubuntu.com/406485/
Mar 30 06:59:40 <kirkland> "If you choose guided partitioning for an entire disk, you will next be asked which disk should be used"
Mar 30 06:59:48 <cjwatson> screenshot?
Mar 30 07:00:04 <kirkland> i'm on real hardware, camera phone screenshot okay?
Mar 30 07:00:19 <kirkland> weird, it's calling the disk sdb
Mar 30 07:00:24 <kirkland> never really did that before
Mar 30 07:00:35 <kirkland> my preseed hardcodes sda
Mar 30 07:00:38 <cjwatson> camera phone is fine
Mar 30 07:00:41 <kirkland> i can change that easily enough
Mar 30 07:00:59 <cjwatson> but yeah, disk name change would account for that
Mar 30 07:01:21 <cjwatson> you can put a script in partman/early_command if you need to compute that dynamically
Mar 30 07:04:19 <kirkland> http://people.canonical.com/~kirkland/IMG_3427.JPG
Mar 30 07:06:39 <cjwatson> right, for some reason /dev/sda must not exist, I have no idea why
Mar 30 07:06:49 <cjwatson> you'll probably also need to add:
Mar 30 07:06:55 <cjwatson> d-i partman/confirm_nooverwrite boolean true
Mar 30 07:07:05 <cjwatson> to avoid problems later in some configurations
Mar 30 07:08:57 <kirkland> cjwatson: okay, i'll add that now
Mar 30 07:09:14 <kirkland> cjwatson: s/sda/sdb/ solved my immediate problem, while i go hack a better solution
Mar 30 07:20:24 <kirkland> arg, yeah, bummer... I have two slightly different machines i need to preseed 5 different installs against, and one is seeing its disk as sda and the other as sdb
Mar 30 07:22:35 <cjwatson> kirkland: does any of them have more than one disk?
Mar 30 07:22:52 <kirkland> cjwatson: no, they don't
Mar 30 07:23:13 <cjwatson> kirkland: then just leave out partman-auto/disk - you don't need to set it on a single-disk machine
Mar 30 07:23:14 <kirkland> cjwatson: i was just checking if i plugged a stray sd card in or something
Mar 30 07:23:16 <kirkland> no dice
Mar 30 07:23:22 <kirkland> cool
Mar 30 07:23:25 <kirkland> let me try that
Mar 30 07:23:44 <cjwatson> if partman-auto/method is set and there's only one disk, then it will just autopartition the first disk, whatever that is
Mar 30 07:23:56 <kirkland> cjwatson: what about grub-installer/bootdev ?
Mar 30 07:24:12 <cjwatson> you shouldn't normally need to set that either
Mar 30 07:24:39 * kirkland comments out those two and retests
Mar 30 07:25:09 <cjwatson> you're already preseeding grub-installer/only_debian and grub-installer/with_other_os to true, which should mean that grub-installer/bootdev won't generally be asked
Mar 30 07:28:15 <kirkland> cjwatson: sweet, that works ;-)

[Thierry Carrez (ttx)]

Looking at ISO and netboot installer syslog in detail, it appears to be finding a removable disk that I didn't suspect existed. On post-beta1 netboot, it finds it before disk. On ISO (or old netboots), it finds the disk before.

Different ordering is not a bug, so closing, sorry for the noise.