it gave me no peace; Wi-Fi works! I can now access the system again with ssh:
Using username "root".
Linux DietPi 5.10.60-v7+ #1449 SMP Wed Aug 25 15:00:01 BST 2021 armv7l
The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.
Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Sat Sep 18 00:29:08 2021
─────────────────────────────────────────────────────
DietPi v7.6.1 (beta) : 00:37 - Sa 18.09.2021
─────────────────────────────────────────────────────
- Device model : RPi 3 Model B (armv7l)
- Uptime : up 10 minutes
- CPU temp : 45'C : 113'F (Optimal temperature)
- LAN IP : 192.168.115.143 (wlan0)
- Freespace (RootFS) : 1,6G
- Freespace (userdata) : 1,6G
- MOTD : DietPi Beta v7.6 is up for testing:
https://github.com/MichaIng/DietPi/issues/4728
─────────────────────────────────────────────────────
DietPi Team : MichaIng (lead), Daniel Knight (founder), Joulinar (support)
Image by : DietPi Core Team (pre-image: Raspbian Lite)
Web : https://dietpi.com | https://twitter.com/DietPi_
Patreon Legends : Camry2731
Contribute : https://dietpi.com/contribute.html
DietPi Hosting : Powered by https://myvirtualserver.com
dietpi-launcher : All the DietPi programs in one place
dietpi-config : Feature rich configuration tool for your device
dietpi-software : Select optimised software for installation
htop : Resource monitor
cpu : Shows CPU information and stats
root@DietPi:~#
Now still the Baikal calendar to run again . . .
successfully:
Dashboard
About this system
Version
This systems runs Baïkal 0.8.0
http://sabre.io/baikal
Services
Web admin On
CalDAV On
CardDAV On
License and credits
Baïkal is open source software licensed under the terms of the GNU GPL v3.
Baïkal is based upon other open source projects.
Read the README.md file to learn about that.
Baïkal was created by Jérôme Schneider
and is now developed by volunteers on GitHub.
Statistics
Users
Registered users 2
CalDAV
Number of calendars 4
Number of events 168
CardDAV
Number of address books 0
Number of contacts 0
Now I testing eth0 . . .
root@DietPi:~# sudo ifup eth0
Internet Systems Consortium DHCP Client 4.4.1
Copyright 2004-2018 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/
Cannot find device "eth0"
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.
ifup: failed to bring up eth0
root@DietPi:~#
There cannot be a hardware error, because eth0 works with a DietPi installation on another SD card.