[Bug 2008952] Re: DNS failure while trying to fetch user-data

[Chad Smith]

I can confirm Dan's validation that After=systemd-resolved.service doesn't buy us anything here because, although systemd-resolved.service is up, NetworkManager.service && NetworkManager-wait-online.service don't finish bringing link up for related network devices until After=dbus.service timeframe. So blocking on systemd-resolved.service tells us only that the service is running, not that it provides useful DNS lookups.


Since dbus.service is After=sysinit.target and sysinit.target is After=cloud-init.service we have an ordering cycle for NetworkManager that doesn't exist for systemd-networkd controlled environments.  Any attempts to include After=NetworkManager-wait-online.service in cloud-init.service definition result in ordering cycles. Even if we try to add DefaultDependecies=no to both NetworkManager.service and NetworkManager-wait-online.service to prevent them from pulling in `After=sysinit.target` for ordering.


NetworkManager images (desktop) differ from cloud-init's systemd-networkd managed images (server) because systemd-networkd-wait-online.service doesn't have a strict After=dbus.service config systemd-networkd can poll for dbus availability and use it once it's available. But, it doesn't seem NetworkManager has that facility though I haven't dug deeply into NM yet.

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Title:
  DNS failure while trying to fetch user-data

Status in cloud-init:
  Triaged
Status in netplan:
  Invalid
Status in subiquity:
  New
Status in systemd package in Ubuntu:
  New

Bug description:
  In testing netboot + autoinstall of the new ubuntu desktop subiquity
  based installer for 23.04 I found cloud-init is failing to retrieve
  user-data because it can't resolved the hostname in the URL.  This
  same configuration does work for 22.04 based subiquity, so seems a
  regression.

  From the ipxe config:

  imgargs vmlinuz initrd=initrd \
   ip=dhcp \
   iso-url=http://cdimage.ubuntu.com/daily-live/pending/lunar-desktop-amd64.iso \
   fsck.mode=skip \
   layerfs-path=minimal.standard.live.squashfs \
   autoinstall \
   'ds=nocloud-net;s=http://boot.linuxgroove.com/ubuntu/23.04/' \

  That fails, but if we replace boot.linuxgroove.com with the IP it
  works.

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