DNS problem with NetworkManager

English Network/Internet
21

Check Yast2 > Netzwerkeinstellungen > Hostname/DNS > Hostnamen über DHCP setzen > wlp2s0. Have IPV4/IPV6 of NetworkManager set to automatisch and all fields empty.

If not successful post the make and model of your router, such as “Speedport W 724V Typ A”, "Thompson TG585v7 " or whatever it is. I will try to elaborate on 1. and 2.

Here is the output of the two commands:

linux:/home/user # journalctl -u NetworkManager  | grep policy
Feb 25 12:31:26 linux NetworkManager[14192]: <debug> [1551094286.9644] policy: re-enabling autoconnect for all connections (only clear no-secrets flag)Feb 25 12:32:46 linux NetworkManager[1318]: <trace> [1551094366.4421] policy: get-hostname: "linux" (from dbus)
Feb 25 12:32:46 linux NetworkManager[1318]: <trace> [1551094366.4421] policy: hostname-original: set to "linux"
Feb 25 12:32:46 linux NetworkManager[1318]: <debug> [1551094366.4424] policy: hostname-mode: full
Feb 25 12:34:29 linux NetworkManager[1318]: <debug> [1551094469.7692] policy: re-enabling autoconnect for all connections (only clear no-secrets flag)
Feb 25 12:35:00 linux NetworkManager[1318]: <trace> [1551094500.0892] device[0x55be9e46b2b0] (wlp2s0): ipv4.route-table = 254 (policy routing not enabled)
Feb 25 12:35:00 linux NetworkManager[1318]: <trace> [1551094500.1036] device[0x55be9e46b2b0] (wlp2s0): ipv6.route-table = 254 (policy routing not enabled)
Feb 25 12:35:00 linux NetworkManager[1318]: <info>  [1551094500.9868] policy: set 'homenetwork' (wlp2s0) as default for IPv4 routing and DNS
Feb 25 12:35:00 linux NetworkManager[1318]: <trace> [1551094500.9870] policy: set-hostname: updating hostname (routing and dns)
Feb 25 12:35:00 linux NetworkManager[1318]: <trace> [1551094500.9870] policy: get-hostname: "linux"
Feb 25 12:35:00 linux NetworkManager[1318]: <trace> [1551094500.9871] policy: get-hostname: "linux"
Feb 25 12:35:00 linux NetworkManager[1318]: <trace> [1551094500.9871] policy: set-hostname: hostname already set to 'linux' (from system configuration)
Feb 25 12:35:01 linux NetworkManager[1318]: <trace> [1551094501.5048] policy: set-hostname: updating hostname (ip6 conf)
Feb 25 12:35:01 linux NetworkManager[1318]: <trace> [1551094501.5049] policy: get-hostname: "linux"
Feb 25 12:35:01 linux NetworkManager[1318]: <trace> [1551094501.5049] policy: get-hostname: "linux"
Feb 25 12:35:01 linux NetworkManager[1318]: <trace> [1551094501.5049] policy: set-hostname: hostname already set to 'linux' (from system configuration)




linux:/home/svater # journalctl -b -u NetworkManager -p5-- Logs begin at Sun 2018-12-02 17:54:27 CET, end at Mon 2019-02-25 13:32:48 CET. --
Feb 25 12:35:46 linux NetworkManager[1318]: <warn>  [1551094546.6991] dhcp6 (wlp2s0): request timed out
Feb 25 13:12:00 linux NetworkManager[1318]: <warn>  [1551096720.9865] sup-iface[0x55be9e36c0d0,wlp2s0]: connection disconnected (reason -3)
Feb 25 13:12:59 linux NetworkManager[1318]: <warn>  [1551096779.3200] dhcp6 (wlp2s0): request timed out



On the working machine, I have also the "request timed out", but not the sup-iface message.

Any clues?

I am currently using Xubuntu, Fedora 29 and Tumbleweed. All of them have the same clean NetworkManager journal entries as posted previously.

22

From your problem machine, ping an internet address by name to verify it works.
If that works, then take a look at your web broser settings, look for your web proxy setting, it should ordinarily be set up to automatically look for a web proxy, and if found then configure your web browser to connect to the Internet differently than the rest of your system.
Disable automatic proxy configuration unless you’re specifically instructed to use a web proxy.

Also, when you use your web browser to test various addresses, always test a new and different address to avoid caching issues (although aPage Reload should normally address even cached errors).

TSU

23

Okay, somehow I have a solution. I seems to be a problem with nscd.

rcnscd stop

and everything works again. Hopefully, this will keep. It would be interesting what changed with my update, since I never had problems before. Thanks to Jiri https://lists.opensuse.org/opensuse-support/2019-02/msg00148.html for pointing this out to me.

24

You may check your nscd for integrity. I have:

erlangen:~ # rpm -V nscd-2.29-1.3.x86_64
erlangen:~ #

nscd is up and running since updating to kernel 4.20.10-1-default without causing trouble:

erlangen:~ # journalctl -b|grep nscd
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring file `/etc/passwd` (1)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring directory `/etc` (2)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring file `/etc/group` (3)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring directory `/etc` (2)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring file `/etc/hosts` (4)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring directory `/etc` (2)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 disabled inotify-based monitoring for file `/etc/resolv.conf': No such file or directory
Feb 25 18:24:37 erlangen nscd[1024]: 1024 stat failed for file `/etc/resolv.conf'; will try again later: No such file or directory
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring file `/etc/services` (5)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring directory `/etc` (2)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring file `/etc/netgroup` (6)
Feb 25 18:24:37 erlangen nscd[1024]: 1024 monitoring directory `/etc` (2)
Feb 25 18:24:54 erlangen nscd[1024]: 1024 monitored file `/etc/resolv.conf` changed (mtime)
Feb 25 18:24:54 erlangen nscd[1024]: 1024 monitoring file `/etc/resolv.conf` (7)
Feb 25 18:24:54 erlangen nscd[1024]: 1024 monitoring directory `/etc` (2)
erlangen:~ #