[Bug 1813394] Re: DROPBEAR_IFDOWN=* takes interface down but leaves netplan config

[Dan Podeanu]

Patch for /usr/share/initramfs-tools/scripts/init-bottom/dropbear on
Ubuntu 22.04-LTS

This feels like the better place, as it respects dropbear's original
semantic for IFDOWN on systems which run netplan. Needs to be followed
by update-initramfs -u -k 'all'

---- /root/dropbear-orig	2022-12-27 10:50:51.619568832 +0000
+++ /usr/share/initramfs-tools/scripts/init-bottom/dropbear	2022-12-27 10:56:21.291398517 +0000
@@ -79,6 +79,12 @@
         ip link    set   dev "$IFACE" down
         ip address flush dev "$IFACE"
         ip route   flush dev "$IFACE"
+
+        if [ -f "/run/netplan/${IFACE}.yaml" ]; then
+            rm -f "/run/netplan/${IFACE}.yaml"
+
+        fi
+
         log_end_msg
     done
 fi

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to initramfs-tools in Ubuntu.
https://bugs.launchpad.net/bugs/1813394

Title:
  DROPBEAR_IFDOWN=* takes interface down but leaves netplan config

Status in clevis package in Ubuntu:
  Confirmed
Status in dropbear package in Ubuntu:
  Confirmed
Status in initramfs-tools package in Ubuntu:
  Confirmed

Bug description:
  On bionic, setting the network interface up (e.g. eno1) with DHCP now
  causes a /run/netplan/eno1.yaml and a /run/net-eno1.conf file to be
  written. The former gets imported by netplan after boot and causes the
  DHCP lease from the initrd to be around forever, which I think goes
  against the intent of DROPBEAR_IFDOWN=*.

  I have brewed up a workaround script that lives in /etc/initramfs-
  tools/scripts/init-bottom/hack-delete-netif-netplan.sh for now:

  
  #### ---- 8< cut >8 --------
  #!/bin/sh

  PREREQ=""

  prereqs() {
          echo "$PREREQ"
  }

  case "$1" in
          prereqs)
                  prereqs
                  exit 0
          ;;
  esac

  . /scripts/functions

  log_begin_msg "Deleting all network configuration that systemd could try to import"
  rm /run/net-*.conf
  rm /run/netplan/*.yaml
  log_end_msg
  #### ---- 8< cut >8 --------

  I think that dropbear-intiramfs's init-bottom script should do this in
  addition to downing the interfaces that it finds via the
  DROPBEAR_IFDOWN pattern. Do you agree?

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/clevis/+bug/1813394/+subscriptions