Package: ifupdown
Version: 0.8.35
Followup-For: Bug #923640
Dear Maintainer,
This bug is seemingly due to misguided single-stack DHCPv4 servers
that are still
found in the wild. If dhclient sents a client identifier at all, they
will NAK
and not respond. Hence the previous report of being able to obtain an
IP address
via a manual 'dhclient eth0', which will default to not using the
'-i' option
that is now the default in ifupdown (see #906894).
On my installation I have confirmed the following (options setting
pid files and leases files removed for brevity, they
do not
change anything):
dhclient -4 -v -I works
dhclient -4 -v -i -I fails with a DHCPNAK from the server
dhclient -4 -v -I fails if 'send dhcp-client-identifier' is set in
/etc/dhcp/dhclient.conf [a non-exhaustive search of possible
identifiers ahs yet to find one that the server will accept].
A possible solution is to add a configuration option for
/etc/network/interfaces to enable/disable this on a per-interface
basis. Or to be able to flag an interface as 'legacy v4' or similar
and entirely disable v6 and related features.
Severity has been flagged as important because this results in an
unusable system silently across upgrade if you're on a network with
such a server.
Yours,
Ian Abel
-- Package-specific info:
--- /etc/network/interfaces:
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
source /etc/network/interfaces.d/*
# The loopback network interface
auto lo
iface lo inet loopback
auto enp0s31f6
iface enp0s31f6 inet dhcp
--- /etc/network/interfaces.d/*:
cat: '/etc/network/interfaces.d/*': No such file or directory
--- up and down scripts installed:
/etc/network/if-down.d:
total 4
-rwxr-xr-x 1 root root 372 Jul 30 2018 openvpn
/etc/network/if-post-down.d:
total 0
lrwxrwxrwx 1 root root 23 Oct 10 04:17 avahi-daemon -> ../if-up.d/avahi-daemon
/etc/network/if-pre-up.d:
total 4
-rwxr-xr-x 1 root root 344 Jun 30 2016 ethtool
/etc/network/if-up.d:
total 12
-rwxr-xr-x 1 root root 484 Apr 27 2018 avahi-daemon
-rwxr-xr-x 1 root root 1685 Jun 30 2016 ethtool
-rwxr-xr-x 1 root root 385 Jul 30 2018 openvpn
-- System Information:
Debian Release: buster/sid
APT prefers unstable
APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 4.19.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8),
LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled
Versions of packages ifupdown depends on:
ii adduser 3.118
ii iproute2 4.20.0-2
ii libc6 2.28-8
ii lsb-base 10.2019031300
Versions of packages ifupdown recommends:
ii isc-dhcp-client [dhcp-client] 4.4.1-2
Versions of packages ifupdown suggests:
ii ppp 2.4.7-2+4.1
pn rdnssd <none>
-- no debconf information
