Add ignition.platform.id=metal for bare metal

[cgwalters]

Ref: coreos/fedora-coreos-tracker#142

[dustymabe]

This works since we have a separate kickstart for metal. Do we plan for that to always be the case? Or would we possibly use the "golden image" one day for bare metal too? If so it may be better to use gf-oemid like we do for qemu?

[dustymabe]

One comment/question about approach, otherwise LGTM. Can you make sure that ignition won't barf if it encounters an OEM ID it doesn't know about?

[cgwalters]

Do we plan for that to always be the case?

No - we've talked repeatedly about not using Anaconda right?

If so it may be better to use gf-oemid like we do for qemu?

gf-oemid will fail on EFI layout right now; also doesn't really gain us anything either.

Can you make sure that ignition won't barf if it encounters an OEM ID it doesn't know about?

Looking at the code, it does panic today. So you're definitely right we should fix that before merging.
(Which then argues a bit for adding the parsing support to Ignition itself, but we can continue with the approach from coreos/ignition-dracut#42 for now)

[dustymabe]

FYI the 'metal' platform id was added coreos/ignition#724 . Will be in the next ignition release.

[jlebon]

@cgwalters I think we can just s/coreos.oem/ignition.platform/ and get this in now that coreos/ignition#724 is fixed right?

We need this for bare-metal in FCOS (see coreos/coreos-installer#22 (comment)).

For RHCOS, I think this is working right now because we're always outputting an id even if it's the wrong one: https://github.com/coreos/ignition-dracut/blob/79f5d7adfbb83f088be947f6497f04fbc9de939c/dracut/30ignition/ignition-generator#L98.

[jlebon]

For FCOS, I was playing with:

commit afe77b7313c2fafd3820901c5192249613a0b8e3
Date:   Mon Apr 8 16:05:13 2019 -0400

    dracut/30ignition: default to `metal` platform if none given

    The `metal` platform id is essentially a "no-op" in Ignition. IOW, if
    no specific platform id is given, let's just assume that the config is
    baked in.

diff --git a/dracut/30ignition/ignition-generator b/dracut/30ignition/ignition-generator
index 7d56030..439d784 100755
--- a/dracut/30ignition/ignition-generator
+++ b/dracut/30ignition/ignition-generator
@@ -39,4 +39,4 @@ if $(cmdline_bool 'ignition.firstboot' 0); then
     add_requires ignition-complete.target
 fi

-echo "PLATFORM_ID=$(cmdline_arg ignition.platform.id)" > /run/ignition.env
+echo "PLATFORM_ID=$(cmdline_arg ignition.platform.id metal)" > /run/ignition.env

but I'm thinking now it's probably cleaner to just keep erroring the way we do now (though we could improve that error), instead of having this sort of "default" logic.

[jlebon]

OK, updated! ⬆️
Should be ready to go now.

[bgilbert]

LGTM

[cgwalters]

LGTM

[jcordes73]

How is this supposed to be used? I tried with setting coreos.oem.id=metal and it didn't work for PXE-boot. However after installation I added ignition.platform.id=metal to the kernel boot parameters and this seems to be picked up. I'm using build 29.936.

[jlebon]

This is the id that gets embedded in the raw metal images so that Ignition will know to not try to look elsewhere for an Ignition config and just use the one that was specified at install time. IOW, you shouldn't actually have to type out ignition.platform.id=metal anywhere.