Giving the working note what I'm doing currently: In order to analyze the issue, I tried to remove the /etc/resolv.conf in the normal mode and traced the syslog if any systemd service restored the file. What I observed is NM will go through this line of writing DNS, and reported the warning from calling /etc/resolvconf/update.d/libc:
<info> [1516604239.0578] dns-mgr: Writing DNS information to /sbin/resolvconf warning "/etc/resolv.conf is not a symbolic link to /run/resolvconf/resolv.conf" I'm thinking the /etc/resolv.conf will be dynamically recreated, and then NM moved on to finish its service (so NM is able to keep alive). However, under the recovery mode, the NM can't normally start its service and exit due to catch the signal SIGTERM (not sure if it's related to nm_dispatcher). So seems like we have two problems here: 1. why does NM fail to start 2. why does NM not try to call /etc/resolvconf/update.d/libc to restore the file in the recovery mode -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/1682637 Title: during recovery mode, enable network failed due to /etc/resolv.conf not being present Status in network-manager package in Ubuntu: Confirmed Status in thermald package in Ubuntu: Confirmed Bug description: Something went wrong that required me to boot to recovery mode via grub. The important part here, is that while I got as far as the recovery screen asking to "Enable Networking" and other options fsck filesystems, drop to root shell, etc. and selected "Enable Networking": the result was: grep: /etc/resolv.conf: No such File or directory. Unknown group "power" in message bus configuration file. (Networking did not enable, leaving me stranded at root shell without network which would have made adding/removing packages to troubleshoot easier) Ubuntu: zesty 17.04 Linux: Linux Hedy 4.10.0-19-generic #21-Ubuntu SMP Thu Apr 6 17:04:57 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux network-manager: 1.4.4-1ubuntu3 ProblemType: Bug DistroRelease: Ubuntu 17.04 Package: network-manager 1.4.4-1ubuntu3 ProcVersionSignature: Ubuntu 4.10.0-19.21-generic 4.10.8 Uname: Linux 4.10.0-19-generic x86_64 ApportVersion: 2.20.4-0ubuntu4 Architecture: amd64 CurrentDesktop: XFCE Date: Thu Apr 13 16:40:19 2017 EcryptfsInUse: Yes IfupdownConfig: # interfaces(5) file used by ifup(8) and ifdown(8) auto lo iface lo inet loopback InstallationDate: Installed on 2014-07-09 (1009 days ago) InstallationMedia: Ubuntu-GNOME 14.10 "Utopic Unicorn" - Alpha amd64 (20140708) IpRoute: default via 192.168.250.1 dev wlan1 proto static metric 600 10.0.3.0/24 dev lxcbr0 proto kernel scope link src 10.0.3.1 linkdown 169.254.0.0/16 dev lxcbr0 scope link metric 1000 linkdown 192.168.250.0/24 dev wlan1 proto kernel scope link src 192.168.250.3 metric 600 NetworkManager.conf: [main] plugins=ifupdown,keyfile [ifupdown] managed=false NetworkManager.state: [main] NetworkingEnabled=true WirelessEnabled=true WWANEnabled=false SourcePackage: network-manager UpgradeStatus: Upgraded to zesty on 2017-04-13 (0 days ago) nmcli-dev: DEVICE TYPE STATE DBUS-PATH CONNECTION CON-UUID CON-PATH lxcbr0 bridge connected /org/freedesktop/NetworkManager/Devices/3 lxcbr0 46595dd8-757b-4d93-ade3-c066f72d9e2e /org/freedesktop/NetworkManager/ActiveConnection/0 wlan1 wifi connected /org/freedesktop/NetworkManager/Devices/2 Brisbane House 2b25e748-f9c5-4c84-9fe6-0f64071fcf0b /org/freedesktop/NetworkManager/ActiveConnection/1 eth1 ethernet unavailable /org/freedesktop/NetworkManager/Devices/1 -- -- -- lo loopback unmanaged /org/freedesktop/NetworkManager/Devices/0 -- -- -- nmcli-nm: RUNNING VERSION STATE STARTUP CONNECTIVITY NETWORKING WIFI-HW WIFI WWAN-HW WWAN running 1.4.4 connected started full enabled enabled enabled enabled disabled To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1682637/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
