Coreos-installer: hide --firstboot-args

I see this commit from github:

Is it safe continue to use this option to pass kargs such as: rd.neednet=1 ip=dhcp?

Here’s the story behind:

My use case here is try to automatically install coreos (following @dustymabe’s blog post ) on a bare metal machine using the live ISO with ignition file embeded and to have network and DHCP enabled on the installed system.

Reading this: Host Network Configuration
, it seems like the new ignition spec now spupports kernelArguments.

Am I correct to understand it like this: the installed os will not have network if the kernal args rd.neednet=1 is not present when running the initramfs?
That’s how I understood that I need to supply these 2 args in order to get the network via DHCP working. Or am I totally wrong here?

If I am right, what other alternatives are there to enable the network on the first boot (with ignition file embeded iso)?

Would it be a better approach if I specify these kargs via ignition kernel_arguments instead of running coreos-installer?

Thanks for the help in advance!

There is a lot to unpack here… some comments

  • even though we hid --firstboot-args I can’t imagine fully removing it anytime soon
  • it looks like you just have a default DHCP network environment? great!
    • FCOS by default now will only enable network in the initramfs if it’s needed
      • if you have a remote ignition config or your ignition config has remote resource references, then network (DHCP) will be enabled for you and you don’t have to do anything. If not, then it won’t be brought up.

TL;DR I don’t think you really need to add --firstboot-args with rd.neednet=1 ip=dhcp.

Thanks for the help.

The ignition file actually is embeded into the iso image at the moment. So my case is a bit mixed now.
It does not have any network reference from the file. But I still want to have network setup…

I certainly could serve the ignition file over the wire - I think it should be like that - for the time being I have to use the ignition embedded iso file for a while.

I think I need to supply the rd.neednet =1 ip=dhcp args in some way, right?


If you don’t need networking in the initramfs then why bring it up?

Networking in the real root will still be enabled by default (DHCP).

I think I misunderstood something here.
My mental model was: first boot: no network → real root: no network
The misunderstanding is because an issue I had (no network after the system boots up).
I think my problem lies somewhere else rather than the kernel args…

Thanks for the help.

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