Error Network-wait-online.service

bob_h · December 26, 2024, 7:13pm

nix version 24.11
I’m new to Nixos
Every time do a sudo nixos-rebuild switch it takes up to 3 to 4 minutes to complete and receive error ( Failed to start Network Manager Wait Online ). I have look over the forum and internet but have not found a fix. Looks like this is a common fault.

waffle8946 · December 27, 2024, 1:22am

Disable the service, if you want, but why would it fail to start if you’re connected to the internet? You should investigate that.

Atemu · December 27, 2024, 9:33am

github.com/NixOS/nixpkgs

NetworkManager's nm-online kills nixos-rebuild

opened 10:45PM - 04 Jul 22 UTC

tbidne

0.kind: bug 6.topic: nixos

### Describe the bug The systemd service `NetworkManager-wait-online.service`… can prevent `nixos-rebuild` from succeeding: ``` warning: the following units failed: NetworkManager-wait-online.service × NetworkManager-wait-online.service - Network Manager Wait Online Loaded: loaded (/etc/systemd/system/NetworkManager-wait-online.service; enabled; vendor preset: enabled) Drop-In: /nix/store/k5yq51spcggip2h6aq1y0bydkpr4zahc-system-units/NetworkManager-wait-online.service.d └─overrides.conf Active: failed (Result: exit-code) since Tue 2022-07-05 10:18:52 NZST; 36ms ago Docs: man:nm-online(1) Process: 1258376 ExecStart=/nix/store/b4yhg54s70i0v0k1qnnv8vnja6018yrh-networkmanager-1.38.2/bin/nm-online -s -q (code=exited, status=1/FAILURE) Main PID: 1258376 (code=exited, status=1/FAILURE) IP: 0B in, 0B out CPU: 22ms Jul 05 10:17:52 nixos systemd[1]: Starting Network Manager Wait Online... Jul 05 10:18:52 nixos systemd[1]: NetworkManager-wait-online.service: Main process exited, code=exited, status=1/FAILURE Jul 05 10:18:52 nixos systemd[1]: NetworkManager-wait-online.service: Failed with result 'exit-code'. ``` This service runs `nm-online -s -q`, and the `nm-online` man page says: ``` -s | --wait-for-startup Wait for NetworkManager startup to complete, rather than waiting for network connectivity specifically. Startup is considered complete once NetworkManager has activated (or attempted to activate) every auto-activate connection which is available given the current network state. This corresponds to the moment when NetworkManager logs "startup complete". This mode is generally only useful at boot time. After startup has completed, nm-online -s will just return immediately, regardless of the current network state. There are various ways to affect when startup complete is reached. For details see NetworkManager-wait- online.service(8). ``` > **This corresponds to the moment when NetworkManager logs "startup complete". This mode is generally only useful at boot time.** I am not familiar with this tool, but my experience is that after my laptop has been up for some time (e.g. days), `nm-online` will often return an error code rather than correctly determine the network is up, thus killing any future `nixos-rebuild` commands. ### Steps To Reproduce Steps to reproduce the behavior: 1. Get your machine in a state where `nm-online -s -q` does not return success (not sure how to do this on demand). 2. Witness `nixos-rebuild` failure. ### Expected behavior `nixos-rebuild` should not fail due to an erroneous network check. ### Additional context This is tricky as it is not a `nix` issue per se but rather an issue with a presumably flaky systemd service. It is easy enough to disable this service manually: ```nix systemd.services.NetworkManager-wait-online.enable = false; ``` And perhaps this is the best solution. But a number of my coworkers all ran into this issue independently, so I thought it merited an issue for discoverability, if nothing else. My gut reaction is that a flaky check should probably not be required by default, but I don't know enough about this service's importance/fragility to say. This issue was noticed only recently, both on `nixos-unstable` and `nixos-22.05`. ### Notify maintainers ### Metadata Please run `nix-shell -p nix-info --run "nix-info -m"` and paste the result. ```console [user@system:~]$ nix-shell -p nix-info --run "nix-info -m" - system: `"x86_64-linux"` - host os: `Linux 5.15.47, NixOS, 22.05 (Quokka)` - multi-user?: `yes` - sandbox: `yes` - version: `nix-env (Nix) 2.8.1` - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos` ``` Thanks!

bob_h · December 27, 2024, 11:13am

Thanks Atemu,
I will just wait for next version. In the mean time back to Gentoo.

Atemu · December 27, 2024, 11:23am

That bug is not yet fixed and we don’t know whether it will be fixed until the next version. We don’t even really know how it’s caused yet. Any research in that regard would be much appreciated.

A workaround is to simply disable the wait-online service.