[20:58] <realtime-neil> Using the directions here (https://ubuntu.com/server/docs/install/autoinstall-quickstart) I can duplicate that workflow. But, if I change the iso from https://releases.ubuntu.com/focal/ubuntu-20.04-live-server-amd64.iso to https://releases.ubuntu.com/bionic/ubuntu-18.04.4-live-server-amd64.iso, it doesn't work.
[20:59] <realtime-neil> What's allowing the focal live server iso to work in this case? What does the bionic live server iso lack?
[21:00] <realtime-neil> I suspect something in the casper/initrd, but I can't say for certain
[21:17] <xnox> realtime-neil:  hi, multiple things in livecd-rootfs, how the squashfs are constructed, and how the initrd is built (casper), make many new features work in focal and not on bionic.
[21:17] <xnox> realtime-neil:  at the moment autoinstall is only supported on focal and up.
[21:18] <realtime-neil> ah, okay, gotcha
[21:18] <xnox> realtime-neil:  specifically cloud-init is configured differently, and ssh is missing.
[21:18] <realtime-neil> xnox:  is there a workaround I can use with bionic?
[21:18] <xnox> realtime-neil:  so far we were not tempted to backport all the things to bionic to enable autoinstall in bionic =/ as focal is so awesome, everybody should migrate to focal and totally will next month =) right :-) ?! =)
[21:19] <realtime-neil> xnox: RIGHT!
[21:19]  * xnox goes back to the fantasy land, where people adopt the new Ubuntu LTS the week before it ships point release.
[21:19] <realtime-neil> xnox: would it be absolutely insane to use the focal kernel-initrd pair to grab a bionic iso with the `url=` trickery?
[21:24] <xnox> realtime-neil:  that will get you about 70% there, but you will still need to patch bionic iso
[21:24] <xnox> realtime-neil:  i.e. the installer.squashfs needs cloud-init installed and the /etc/cloud/* stuff to be like it is in the focal iso
[21:25] <xnox> realtime-neil:  or you could open a feature request against launchpad.net/subiquity "please make autoinstall work in bionic, kthxbye"
[21:25] <realtime-neil> xnox: I can ask for things! I'm going to do it!
[21:29] <realtime-neil> xnox: is a feature request the same as a Bug, but with a nicer tone? I'm not seeing anything that identifies itself as "feature request".
[21:32] <xnox> realtime-neil:  it's just a bug yes =)
[21:32] <xnox> realtime-neil:  nicer tone, always welcome.
[21:33] <realtime-neil> Is this enough, or should I make a "real" bug? https://answers.launchpad.net/ubuntu/+source/subiquity/+question/692119
[21:33] <xnox> and then you can like casually mention mwhudson that community are requesting autoinstall support in bionic. and like do ^^^^
[21:34] <mwhudson> why am i in this channel!!
[21:35] <mwhudson> anyway, autoinstall for bionic would be possible but also a fiddle
[21:35] <realtime-neil> mwhudson: now you've got my curiosity piqued
[21:36] <realtime-neil> Also, I made this for you, mwhudson: https://bugs.launchpad.net/ubuntu/+source/subiquity/+bug/1889314
[21:45] <realtime-neil> xnox: yep, I'm 70% of the way there: booting qemu with the focal kernel-initrd pair and a url=http://myhost:3003/ubuntu-18.04.4-live-server-amd64.iso gives me "Unable to find a live filesystem on the network"
[21:47] <xnox> realtime-neil:  you can like speficy casper ignore uuid, or specify casper uuid = <bionic uuid> => there is a quick check to ensure one is trying to boot a matching kernel+initrd & iso pari.
[21:47] <xnox> *pair
[21:48] <realtime-neil> xnox: is that a kernel param? which uuid is it referencing?
[21:50] <realtime-neil> got it; added appends `live-media-path=/casper/ ignore_uuid`
[21:50] <realtime-neil> Sweet! That looks a lot better.
[21:52] <xnox> something something man casper something something or like http://manpages.ubuntu.com/manpages/focal/en/man7/casper.7.html
[21:53] <xnox> ignore_uuid sounds a bout right
[21:59] <realtime-neil> I got as far as the disk partitioning; as soon as I confirm the suggested partitioning scheme, it throws "module bcache not found in directory /lib/modules/5.4.0-26-generic"
[21:59] <realtime-neil> I'm guessing that has something to do with the mismatch between the kernel I'm running and the live media I'm using
[22:17] <xnox> realtime-neil:  yeah indeed that will happen.
[22:17] <xnox> realtime-neil:  you could switch to terminal and install the modules for the matching kernel you booted.
[22:17] <xnox> realtime-neil:  i.e. add focal, apt update, install focal's kernel modules.
[22:43] <realtime-neil> xnox: in which part? the casper/installer.squashfs ?
[22:49] <xnox> hm.
[22:49] <xnox> realtime-neil:  you can replace the modules squashfs in casper/extra/* no?
[22:50] <xnox> realtime-neil:  with the right one? inside the bionic image.
[22:50] <xnox> replace it with the one from focal image?
[23:44] <realtime-neil> xnox: ah, okay got it; within the ubuntu-18.04.4-live-server-amd64.iso, replace the `casper/extras/modules.*` with the ones taken from the ubuntu-20.04-live-server-amd64.iso
[23:59] <xnox> realtime-neil:  i hope you understand that at this point you are trying to attach the Hand from the Adam's family, onto frankenstein from a different movie.