Default mDNS settings results in network flooding in networks with reflectors enabled #5435
Description
Describe the issue you are experiencing
The default NetworkManager configuration sets mDNS to yes which, in network having multiple vlans and a reflector (e.g. on a Unifi network), result in a flood of mDNS requests originating from the supervisor's systemd-resolved. I believe the network configuration originates from this line:
https://github.com/home-assistant/supervisor/blame/4e0de93096dc69c257056b36eff0c19b47006850/supervisor/dbus/network/setting/generate.py#L167
Typical flooding would look like this
2024-11-19 15:09:05.941 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant12746' to 'homeassistant12749'.
2024-11-19 15:09:06.214 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12749\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:09:06.214 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12749\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant12749.local
2024-11-19 15:09:06.214 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12749.local IN A 192.168.10.247
2024-11-19 15:09:06.214 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant12749' to 'homeassistant12758'.
2024-11-19 15:09:06.450 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12758\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:09:06.451 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12758\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant12758.local
2024-11-19 15:09:06.451 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12758.local IN A 192.168.10.247
2024-11-19 15:09:06.451 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant12758' to 'homeassistant12764'.
2024-11-19 15:09:06.704 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12764\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant12764.local
2024-11-19 15:09:06.704 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12764\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:09:06.704 homeassistant systemd-resolved[416]: Detected conflict on homeassistant12764.local IN A 192.168.10.247
2024-11-19 15:09:06.704 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant12764' to 'homeassistant12767'.
The issue was also reported under the operating system project, but got closed. Nevertheless, a long discussion continued after the issue got closed, with some hints on how to fix the issue.
home-assistant/operating-system#1163 (comment)
What type of installation are you running?
Home Assistant OS
Which operating system are you running on?
Home Assistant Operating System
Steps to reproduce the issue
- Run Home-Assistant on a network with multiple vlans
- Setup a mDNS reflector to reflect mDNS packets across vlans
- Open the system->logs->host (http://homeassistant.local:8123/config/logs?provider=host)
- Watch for systemd-resolved name collision entries in the log
...
Anything in the Supervisor logs that might be useful for us?
2024-11-19 15:00:45.209 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant11362' to 'homeassistant11363'.
2024-11-19 15:00:45.281 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11363\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11363.local
2024-11-19 15:00:45.281 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11363\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.281 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11363\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.281 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11363\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11363.local
2024-11-19 15:00:45.281 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11363.local IN A 192.168.10.247
2024-11-19 15:00:45.281 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant11363' to 'homeassistant11371'.
2024-11-19 15:00:45.453 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11371\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11371.local
2024-11-19 15:00:45.453 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11371\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.453 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11371.local IN A 192.168.10.247
2024-11-19 15:00:45.453 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant11371' to 'homeassistant11381'.
2024-11-19 15:00:45.515 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11381\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.515 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11381\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11381.local
2024-11-19 15:00:45.515 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11381.local IN A 192.168.10.247
2024-11-19 15:00:45.515 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant11381' to 'homeassistant11382'.
2024-11-19 15:00:45.734 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11382\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.734 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11382\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11382.local
2024-11-19 15:00:45.735 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11382.local IN A 192.168.10.247
2024-11-19 15:00:45.735 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant11382' to 'homeassistant11386'.
2024-11-19 15:00:45.812 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11386\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11386.local
2024-11-19 15:00:45.812 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11386\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.812 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11386.local IN A 192.168.10.247
2024-11-19 15:00:45.812 homeassistant systemd-resolved[416]: Hostname conflict, changing published hostname from 'homeassistant11386' to 'homeassistant11395'.
2024-11-19 15:00:45.957 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11395\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN TXT ""
2024-11-19 15:00:45.957 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11395\032\091431cf3e1addd46f5b14185b1bea39b0e\093._workstation._tcp.local IN SRV 0 0 0 homeassistant11395.local
2024-11-19 15:00:45.957 homeassistant systemd-resolved[416]: Detected conflict on homeassistant11395.local IN A 192.168.10.247
202System Health information
System Information
| version | core-2024.11.2 |
|---|---|
| installation_type | Home Assistant OS |
| dev | false |
| hassio | true |
| docker | true |
| user | root |
| virtualenv | false |
| python_version | 3.12.4 |
| os_name | Linux |
| os_version | 6.6.54-haos |
| arch | x86_64 |
| timezone | America/Toronto |
| config_dir | /config |
Home Assistant Community Store
| GitHub API | ok |
|---|---|
| GitHub Content | ok |
| GitHub Web | ok |
| HACS Data | ok |
| GitHub API Calls Remaining | 5000 |
| Installed Version | 2.0.1 |
| Stage | running |
| Available Repositories | 1536 |
| Downloaded Repositories | 9 |
Home Assistant Cloud
| logged_in | false |
|---|---|
| can_reach_cert_server | ok |
| can_reach_cloud_auth | ok |
| can_reach_cloud | ok |
Home Assistant Supervisor
| host_os | Home Assistant OS 13.2 |
|---|---|
| update_channel | stable |
| supervisor_version | supervisor-2024.11.2 |
| agent_version | 1.6.0 |
| docker_version | 27.2.0 |
| disk_total | 205.1 GB |
| disk_used | 52.1 GB |
| healthy | true |
| supported | true |
| host_connectivity | true |
| supervisor_connectivity | true |
| ntp_synchronized | true |
| virtualization | oracle |
| board | ova |
| supervisor_api | ok |
| version_api | ok |
| installed_addons | File editor (5.8.0), Terminal & SSH (9.15.0), Mosquitto broker (6.4.1), AppDaemon (0.16.7), SQLite Web (4.2.2), Z-Wave JS (0.9.0), ESPHome (2024.10.3), phpMyAdmin (0.10.0), rtl_433 MQTT Auto Discovery (0.8.2), Samba share (12.3.2), Z-Wave JS UI (3.17.0), MariaDB (2.7.1), Zigbee2MQTT (1.41.0-1), MQTT Explorer (browser-1.0.3), Node-RED (18.1.1), Studio Code Server (5.17.3), Frigate Proxy (1.5) |
Dashboards
| dashboards | 3 |
|---|---|
| resources | 1 |
| error | /config/ui-lovelace.yaml not found |
| views | 20 |
| mode | yaml |
Recorder
| oldest_recorder_run | October 24, 2024 at 5:20 PM |
|---|---|
| current_recorder_run | November 19, 2024 at 9:47 AM |
| estimated_db_size | 3032.83 MiB |
| database_engine | mysql |
| database_version | 10.11.6 |
Spotify
| api_endpoint_reachable | ok |
|---|
Supervisor diagnostics
config_entry-hassio-5dae251bf6ea118d92a240060ae3caf8.json
Additional information
In the meantime, I am trying the solution proposed in the following comment
home-assistant/operating-system#1163 (comment)
Which for me was as follow, while connected through ssh.
1- List all connections
> nmcli -m tabular c
NAME UUID TYPE DEVICE
Supervisor enp0s3 502849d7-2609-3319-813c-1622970139ef ethernet enp0s3
lo d5b4fc51-dc86-4e86-99d4-b9652b9b3f59 loopback lo
2- Set mdns mode to resolve on the Supervisor connection
> nmcli connection modify "Supervisor enp0s3" connection.mdns resolve
3- Restart Network Manager
> systemctl restart NetworkManager.service
4- Confirm it works
> resolvectl mdns
Global: yes
Link 2 (enp0s3): resolve
Link 3 (docker0): yes
Link 4 (hassio): yes
I am wondering if this is something that could be exposed to the UI, or if someone has a better solution?