Network failure after server install due to interface rename

[Colin Law]

After fresh install of 14.04.3 server from ubuntu-14.04.3-server-amd64.iso the wired network did not work.
The install went without problems and had no trouble accessing the network via dhcp.

In syslog is:
Nov 1 14:23:51 dibbler-s kernel: [ 2.917909] r8169 0000:06:00.0 eth0: RTL8105e at 0xffffc9000476e000, 00:9c:02:20:38:c7, XID 00a00000 IRQ 28
Nov 1 14:23:51 dibbler-s kernel: [ 3.086027] r8169 0000:06:00.0 em1: renamed from eth0
Nov 1 14:23:51 dibbler-s kernel: [ 3.099888] systemd-udevd[111]: renamed network interface eth0 to em1

and

Nov 1 14:23:53 dibbler-s dhclient: Error getting hardware address for "eth0": No such device

When I look in /etc/network/interfaces I saw
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp

Replacing the last two lines with
auto em1
iface em1 inet dhcp
and restarting networking allowed the network to work correctly.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: debian-installer (not installed)
ProcVersionSignature: Ubuntu 3.19.0-31.36~14.04.1-generic 3.19.8-ckt7
Uname: Linux 3.19.0-31-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.18
Architecture: amd64
Date: Mon Nov 2 08:31:11 2015
InstallationDate: Installed on 2015-11-01 (0 days ago)
InstallationMedia: Ubuntu-Server 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
MachineType: Hewlett-Packard Presario CQ57 Notebook PC
MemoryUsage:
 total used free shared buffers cached
 Mem: 3638996 240872 3398124 696 19076 108864
 -/+ buffers/cache: 112932 3526064
 Swap: 3778556 0 3778556
ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 LANGUAGE=en_GB:en
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-31-generic root=UUID=07c0e3aa-32d8-4ef8-b136-d947e93a3bf2 ro
SourcePackage: debian-installer
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/17/2011
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: F.47
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: 3577
dmi.board.vendor: Hewlett-Packard
dmi.board.version: 24.49
dmi.chassis.asset.tag: Chassis Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnHewlett-Packard:bvrF.47:bd12/17/2011:svnHewlett-Packard:pnPresarioCQ57NotebookPC:pvr068E120000204910000620100:rvnHewlett-Packard:rn3577:rvr24.49:cvnHewlett-Packard:ct10:cvrChassisVersion:
dmi.product.name: Presario CQ57 Notebook PC
dmi.product.version: 068E120000204910000620100
dmi.sys.vendor: Hewlett-Packard