DHCP server addon fails to start after (and before) resetting configuration

[SzDavidHUN]

Describe the issue you are experiencing

Even after resetting config, reinstalling the addon, it would fail to start, even with the default configuration.

Two interesting log messages, there appears when I try to start the addon with the default config:

Multiple interfaces match the same shared network: eth0 enu1u1
Failed to get interface index: No such device

What type of installation are you running?

Home Assistant OS

Which operating system are you running on?

Home Assistant Operating System

Which add-on are you reporting an issue with?

DHCP Server

What is the version of the add-on?

1.4.0

Steps to reproduce the issue

0. Previously I tried to use the addon, but it failed to start with a different error message. Therefore I reset the config to default, and then uninstalled it.
1. (Re)Install DHCP server from Addon store
2. Configuration -> Reset to defaults -> Save
3. Start the addon
4. Observe the error message and stopped service in the Logs tab

System Health information

System Information

version	core-2024.5.5
installation_type	Home Assistant OS
dev	false
hassio	true
docker	true
user	root
virtualenv	false
python_version	3.12.2
os_name	Linux
os_version	6.6.28-haos-raspi
arch	aarch64
timezone	Europe/Budapest
config_dir	/config

Home Assistant Community Store

GitHub API	ok
GitHub Content	ok
GitHub Web	ok
GitHub API Calls Remaining	5000
Installed Version	1.34.0
Stage	running
Available Repositories	1397
Downloaded Repositories	4
HACS Data	ok

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 12.3
update_channel	stable
supervisor_version	supervisor-2024.05.1
agent_version	1.6.0
docker_version	25.0.5
disk_total	28.6 GB
disk_used	9.1 GB
healthy	true
supported	true
board	rpi3-64
supervisor_api	ok
version_api	ok
installed_addons	Advanced SSH & Web Terminal (18.0.0), Nginx Proxy Manager (1.0.1), MariaDB (2.7.1), phpMyAdmin (0.9.1), Mosquitto broker (6.4.1), Dnsmasq (1.8.1), AdGuard Home (5.1.0), DHCP server (1.4.0)

Dashboards

dashboards	4
resources	0
views	6
mode	storage

Recorder

oldest_recorder_run	May 24, 2024 at 14:22
current_recorder_run	May 26, 2024 at 00:34
estimated_db_size	92.93 MiB
database_engine	sqlite
database_version	3.44.2

Sonoff

version	3.7.3 (e240aaf)
cloud_online	1 / 2
local_online	1 / 1

Anything in the Supervisor logs that might be useful for us?

No response

Anything in the add-on logs that might be useful for us?

[06:15:40] INFO: Creating DHCP configuration...
[06:15:41] INFO: Starting DHCP server...
Internet Systems Consortium DHCP Server 4.4.3-P1
Copyright 2004-2022 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/
Config file: /etc/dhcpd.conf
Database file: /data/dhcpd.lease
PID file: /run/dhcp/dhcpd.pid
Wrote 0 deleted host decls to leases file.
Wrote 0 new dynamic host decls to leases file.
Wrote 0 leases to leases file.
Multiple interfaces match the same shared network: eth0 enu1u1
Failed to get interface index: No such device

If you think you have received this message due to a bug rather
than a configuration issue please read the section on submitting
bugs on either our web page at www.isc.org or in the README file
before submitting a bug.  These pages explain the proper
process and the information we find helpful for debugging.

exiting.
s6-rc: info: service legacy-services: stopping
s6-rc: info: service legacy-services successfully stopped
s6-rc: info: service legacy-cont-init: stopping
s6-rc: info: service legacy-cont-init successfully stopped
s6-rc: info: service fix-attrs: stopping
s6-rc: info: service fix-attrs successfully stopped
s6-rc: info: service s6rc-oneshot-runner: stopping
s6-rc: info: service s6rc-oneshot-runner successfully stopped

Additional information

Bit of backstory: I had trouble with AdGuard DHCP server, therefore I disabled it, and installed the Simple DHCP server addon. After I configured it, it failed to start with various errors (even though the UI found the config valid). To make it easier to find the errors, I removed some parts of the configuration, and eventually I just gave up, and used the "Reset to defaults" option in the configuration tab.