Comment 0 for bug 1639398

DNS queries using IPv6 UDP time out and return no result, for example "dig @2001:4860:4860::8888 google.com a" fails in this manner. "dig @2001:4860:4860::8888 google.com a +tcp" succeeds using IPv6 TCP, and "dig @8.8.8.8 google.com a" succeeds using IPv4 UDP. This problem occurs on a virtual machine running on the Windows Server 2016 Hyper-V hypervisor. It is not reproducible on VMware vSphere 6.0. I do not have access to other hypervisors for additonal testing. The problem is also not reproducible on Ubuntu 1404 on Hyper-V. Installing the linux-virtual package makes no difference. See bug 1527902 for what appears to be the same problem in different circumstances.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.4.0-45-generic 4.4.0-45.66
ProcVersionSignature: Ubuntu 4.4.0-45.66-generic 4.4.21
Uname: Linux 4.4.0-45-generic x86_64
AlsaDevices:
 total 0
 crw-rw----+ 1 root audio 116, 1 Nov 4 20:23 seq
 crw-rw----+ 1 root audio 116, 33 Nov 4 20:23 timer
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
Date: Fri Nov 4 23:00:11 2016
HibernationDevice: RESUME=/dev/mapper/ubuntu1604--vg-swap_1
InstallationDate: Installed on 2016-11-04 (0 days ago)
InstallationMedia: Ubuntu-Server 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig'
Lspci:

Lsusb: Error: command ['lsusb'] failed with exit code 1:
MachineType: Microsoft Corporation Virtual Machine
PciMultimedia:

ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcFB: 0 hyperv_fb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-45-generic.efi.signed root=/dev/mapper/hostname--vg-root ro
RelatedPackageVersions:
 linux-restricted-modules-4.4.0-45-generic N/A
 linux-backports-modules-4.4.0-45-generic N/A
 linux-firmware 1.157.4
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/26/2012
dmi.bios.vendor: Microsoft Corporation
dmi.bios.version: Hyper-V UEFI Release v1.0
dmi.board.asset.tag: None
dmi.board.name: Virtual Machine
dmi.board.vendor: Microsoft Corporation
dmi.board.version: Hyper-V UEFI Release v1.0
dmi.chassis.asset.tag: 6978-1102-7319-2300-1885-2380-34
dmi.chassis.type: 3
dmi.chassis.vendor: Microsoft Corporation
dmi.chassis.version: Hyper-V UEFI Release v1.0
dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev1.0:bd11/26/2012:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev1.0:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev1.0:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev1.0:
dmi.product.name: Virtual Machine
dmi.product.version: Hyper-V UEFI Release v1.0
dmi.sys.vendor: Microsoft Corporation