This possibly arises from bug #1003842. What is possibly happening: the second or third nameserver on the list of available nameservers supplied to dnsmasq replies quickly to dnsmasq's query with a negative answer and dnsmasq immediately passes that negative answer back to the resolver.
When dnsmasq is not used, the resolver tries the first nameserver on the list first, only trying the second nameserver after a timeout period. If this is the problem then the "correct" solution is to fix the malfunctioning nameserver or to remove it from the list. ** Changed in: dnsmasq (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dnsmasq in Ubuntu. https://bugs.launchpad.net/bugs/1522057 Title: DNS resolution stops working after some time Status in dnsmasq package in Ubuntu: Incomplete Status in network-manager package in Ubuntu: Confirmed Bug description: DNS resolution stops working after sometime (usually 10-20 minutes) in Lubuntu 15.10 The problem can be temporarily corrected after restarting network- manager using systemctl, but it starts again after 10-20 minutes. Looks like network-manager is not configuring dnsmasq properly. Output from 'nslookup google.com': ~~~~~ Server: 127.0.1.1 Address: 127.0.1.1#53 ** server can't find google.com: REFUSED ~~~~~ Output from 'tcpdump -i lo port 53' while running above command: ~~~~~ 20:16:59.235879 IP localhost.38045 > comp0.arhome.info.domain: 28529+ A? google.com. (28) 20:16:59.286851 IP comp0.arhome.info.domain > localhost.38045: 28529 Refused 0/0/0 (28) ~~~~~ ProblemType: Bug DistroRelease: Ubuntu 15.10 Package: network-manager 1.0.4-0ubuntu5.1 ProcVersionSignature: Ubuntu 4.2.0-18.22-generic 4.2.3 Uname: Linux 4.2.0-18-generic x86_64 ApportVersion: 2.19.1-0ubuntu5 Architecture: amd64 CRDA: country IN: DFS-JP (2402 - 2482 @ 40), (N/A, 20), (N/A) (5170 - 5250 @ 80), (N/A, 20), (N/A) (5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS (5735 - 5835 @ 80), (N/A, 20), (N/A) CurrentDesktop: LXDE Date: Wed Dec 2 20:14:32 2015 IfupdownConfig: # interfaces(5) file used by ifup(8) and ifdown(8) auto lo iface lo inet loopback InstallationDate: Installed on 2015-09-25 (68 days ago) InstallationMedia: Lubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422) IpRoute: default via 172.16.84.1 dev wlan0 proto static metric 600 172.16.84.0/22 dev wlan0 proto kernel scope link src 172.16.84.50 metric 600 200.1.1.2 via 172.16.84.1 dev wlan0 proto dhcp metric 600 NetworkManager.state: [main] NetworkingEnabled=true WirelessEnabled=true WWANEnabled=true WimaxEnabled=true SourcePackage: network-manager UpgradeStatus: Upgraded to wily on 2015-11-06 (25 days ago) nmcli-dev: DEVICE TYPE STATE DBUS-PATH CONNECTION CON-UUID CON-PATH wlan0 wifi connected /org/freedesktop/NetworkManager/Devices/1 nn0.arhome.info bab29dc2-8a79-4170-8253-277286712124 /org/freedesktop/NetworkManager/ActiveConnection/0 eth0 ethernet unavailable /org/freedesktop/NetworkManager/Devices/2 -- -- -- vboxnet0 ethernet unmanaged /org/freedesktop/NetworkManager/Devices/3 -- -- -- lo loopback unmanaged /org/freedesktop/NetworkManager/Devices/0 -- -- -- nmcli-nm: Error: command ['nmcli', '-f', 'all', 'nm'] failed with exit code 2: Error: Object 'nm' is unknown, try 'nmcli help'. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/1522057/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp