This is a re-report of https://bugs.launchpad.net/ubuntu/+source/linux/+bug/401202 since that one was apparently closed as no-fix simply because it was too old.
This still occurs in xenial.
Original description:
Regardless of ndots option in /etc/resolv.conf, when NXDOMAIN is returned from the DNS server then resolver always try another attempt with the original name extended by what is in search option.
For example, if you're looking for very.long.url.nowhere and there is a line "search ubuntu.com" in resolv.conf you will get addres of server very.long.url.nowhere.ubuntu.com if such exists. It is incorrect, it should occurs only for urls having less that ndots option dots in its name.
My system is a standard Ubuntu Xenial desktop amd64 using network manager and the default configured Wired Connection 1 (i.e. DHCP).
To reproduce:
- sudo install /dev/fd/0 /etc/NetworkManager/dnsmasq.d/domain <<<'log-queries=extra'
- sudo killall dnsmasq
- ping some.long.non-existent.name
- Watch /var/log/syslog
In my case:
Mar 20 23:19:22 eragon dnsmasq[27367]: 46 127.0.0.1/40646 query[A] some.long.non-existent.name from 127.0.0.1
Mar 20 23:19:22 eragon dnsmasq[27367]: 46 127.0.0.1/40646 forwarded some.long.non-existent.name to 192.168.5.1
Mar 20 23:19:22 eragon dnsmasq[27367]: 46 127.0.0.1/40646 reply some.long.non-existent.name is NXDOMAIN
Mar 20 23:19:22 eragon dnsmasq[27367]: 47 127.0.0.1/52417 query[A] some.long.non-existent.name.sebunger.dnsalias.org from 127.0.0.1
Mar 20 23:19:22 eragon dnsmasq[27367]: 47 127.0.0.1/52417 forwarded some.long.non-existent.name.sebunger.dnsalias.org to 192.168.5.1
Mar 20 23:19:23 eragon dnsmasq[27367]: 47 127.0.0.1/52417 reply some.long.non-existent.name.sebunger.dnsalias.org is <CNAME>
Mar 20 23:19:23 eragon dnsmasq[27367]: 47 127.0.0.1/52417 reply sebunger.dnsalias.org is 203.173.156.30
My /etc/resolv.conf (which is a sym-link to ../run/resolvconf/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 127.0.1.1
search sebunger.dnsalias.org
options ndots:1
(I added the options ndots with no effect)
---
ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-id', '/dev/snd/by-path', '/dev/snd/pcmC1D0c', '/dev/snd/controlC1', '/dev/snd/hwC0D0', '/dev/snd/pcmC0D2c', '/dev/snd/pcmC0D1c', '/dev/snd/pcmC0D1p', '/dev/snd/pcmC0D0c', '/dev/snd/pcmC0D0p', '/dev/snd/controlC0', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
DistroRelease: Ubuntu 16.04
EcryptfsInUse: Yes
IwConfig:
enp2s0 no wireless extensions.
lo no wireless extensions.
MachineType: Gigabyte Technology Co., Ltd. GA-MA770-UD3
NonfreeKernelModules: nvidia_uvm nvidia
Package: linux (not installed)
ProcFB:
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-66-generic root=/dev/mapper/vg0-root ro rootdelay=120 quiet splash
ProcVersionSignature: Ubuntu 4.4.0-66.87-generic 4.4.44
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon.
RelatedPackageVersions:
linux-restricted-modules-4.4.0-66-generic N/A
linux-backports-modules-4.4.0-66-generic N/A
linux-firmware 1.157.8
RfKill:
Tags: xenial xenial
Uname: Linux 4.4.0-66-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm audio cdrom dialout dip floppy kvm lpadmin plugdev sambashare ssh sudo users video
_MarkForUpload: True
dmi.bios.date: 06/12/2009
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: FB
dmi.board.name: GA-MA770-UD3
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrFB:bd06/12/2009:svnGigabyteTechnologyCo.,Ltd.:pnGA-MA770-UD3:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-MA770-UD3:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: GA-MA770-UD3
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1674273
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.