netboot.xyz in Docker

Recently I tried out both the official netbook.xyz and the LinuxServer.io Version of netboot.xyz in a Docker Container using docker-compose. With both containers I wasn’t able to pull the netboot file from the TFTP server within the container. In the docker logs I saw an permission denied error message of the TFTP Daemon. I was not sure how to solve this, but changing the network from „bridge“ to „host“ solved the issue. Just add a

network: host
network_mode: "host"

depending on your docker-compose version.


Power Consumption Cisco 9300 and 9200L

Here are two numbers for anyone who is interested in „real life“ power consumption of these switches:

Cisco 9300-24P with a NM-8X, 715W Power Supply: 83 Watts
Cisco 9200L-24P, 600W Power Supply : 40 Watts

Both switches with no config (factory default) and in idle state (no devices attached). Without the NM-8X of the 9300 the power consumption is about 80Watts.

I think the value for the 9300 switch is kinda high for a more or less actual device in 2023 in an idle state.


SMA Energymeter Analyzer Tool with SQL and MQTT

I wrote a little tool for the SMA Energymeter. The tool can just print the data to console (once or every second) or export the data to MQTT or mySQL.

Check it out on https://home.contes.eu.

andreas@ds-logger:~$ ./smaemtool --break --mqtt --sql
Version 1.0
Timestamp: 24.02.2023 16:19:22
Unix timestamp: 1677251962
Break set, running only once.
MQTT set, export to MQTT enabled.
SQL set, export to SQL enabled.
Listening for multicast packets on
Received 600 bytes from
Power Import:    492 W
Power Export:    0 W
Phase 1 Import:  88 W
Phase 2 Import:  346 W
Phase 3 Import:  57 W
Phase 1 Export:  0 W
Phase 2 Export:  0 W
Phase 3 Export:  0 W
Message sent to MQTT broker on topic smaemtool.
Starting SQL export to server, Database PV.
Data successfully inserted into table smaemtool.

German translation for SEO:
Ich habe ein kleines Tool für das SMA Energymeter geschrieben. Das Tool kann die Daten einfach auf der Konsole ausgeben (einmal oder jede Sekunde) oder die Daten nach MQTT oder mySQL exportieren.