[Resolvconf-devel] Bug#783596: resolvconf: Nameservers aren't set for interfaces with multiple IPs on them

[Serge Shpikin]

Package: resolvconf
Version: 1.76.1
Severity: normal

Dear Maintainer,

I have several IPs assigned to the interface. It's bridged but I don't think it's related. The problem is that nameservers are only being written to /etc/resolv.conf if they're specified in the last section OR if each section has an alias. For example this does not work (/etc/resolv.conf only contains the header and no nameservers):

iface pan0 inet static
  address 192.168.1.2
  netmask 255.255.255.0
  dns-nameservers 8.8.8.8 8.8.4.4

iface pan0 inet static
  address 192.168.252.1
  netmask 255.255.255.0

iface pan0 inet static
  address 172.17.0.1
  netmask 255.255.255.0

This works:

iface pan0 inet static
  address 192.168.1.2
  netmask 255.255.255.0

iface pan0 inet static
  address 192.168.252.1
  netmask 255.255.255.0

iface pan0 inet static
  address 172.17.0.1
  netmask 255.255.255.0
  dns-nameservers 8.8.8.8 8.8.4.4

This also works as expected:

iface pan0 inet static
  address 192.168.1.2
  netmask 255.255.255.0
  dns-nameservers 8.8.8.8 8.8.4.4

iface pan0:bt inet static
  address 192.168.252.1
  netmask 255.255.255.0

iface pan0:other inet static
  address 172.17.0.1
  netmask 255.255.255.0

I see that the method without aliases is preferred as the other one is called "legacy" and I found out that it doesn't work as it should. It's like each subsequent section overwrites the resolvconf's settings so the only way for it to work is to set nameservers in the last one.

-- System Information:
Debian Release: 8.0
  APT prefers testing
  APT policy: (800, 'testing'), (700, 'stable'), (600, 'unstable'), (500, 'oldoldstable'), (500, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.0.0-pf2bfs+ (SMP w/2 CPU cores; PREEMPT)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages resolvconf depends on:
ii  debconf [debconf-2.0]  1.5.56
ii  ifupdown               0.7.53.1
ii  init-system-helpers    1.22
ii  initscripts            2.88dsf-59
ii  lsb-base               4.1+Debian13+nmu1

resolvconf recommends no packages.

resolvconf suggests no packages.

-- debconf information:
  resolvconf/link-tail-to-original: false
  resolvconf/downup-interfaces:
  resolvconf/linkify-resolvconf: true
  resolvconf/reboot-recommended-after-removal: