IOT2050 Ubuntu docker telegraf

Hi,

the ubuntu-arm64-image for the SIMATIC iot2050 which was created on GitHub (https://github.com/siemens/meta-iot2050/tree/jan/ubuntu) works great!

I added a Telegraf binary for logging the system and installed docker manually, but now I am supposed to integrate this setup into the build....in other words to modify the image build process directly (custom image generation).
The client should not have to do anything much further than placing the image on an usbstick and installing it on the iot2050.

I did the telegraf configuration just like here (only the telegraf section)

https://github.com/Tornado3P9/Konsolentools/blob/master/telegraf-influxdb-grafana-on-arm64.txt

And after that I automated the startup with systemd.

Optionally: installing telegraf via docker (sudo apt install docker.io => docker pull telegraf ….more or less) ...though maaaybee being easier for the client, still needs some commands to be entered.

You basically have two options to pre-integrate what you need on top of that image:

• leave the image build unchanged, do your customization live on a device, then use the resulting image as "golden image" for redistribution
• create an Isar layer that describes the installation steps in form of Debian packaging rules and Isar recipes, installing them as part of a custom image build

I know we have grafana/influxdb/telegraf in use internally in Isar. Just checked the recipes, and those use the prebuilt packages from grafana, e.g. recipes-3rdparty/grafana/grafana_8.1.6.bb:

inherit dpkg-prebuilt

SRC_URI = "https://dl.grafana.com/oss/release/${PN}_${PV}_${DISTRO_ARCH}.deb"
SRC_URI[sha256sum] = \
    "aef49df5d71efc87e04a8e0cf9a303e6909b4d521e05d08311cee68da8683740"

On top, you would need rules to do your specific configuration.

How about a third option:

Could you not also just add a "download-setupscript-and-execute" command to the image so that it will get the setupscript.sh at first boot from another server and install any additional features and  programs? Like so:

Manually adding a service to systemd:

install -m 644 ${MY_SETUP_SERVICE} /usr/lib/systemd/system/setup.service
ln -sf /usr/lib/systemd/system/setup.service /etc/systemd/system/multi-user.target.wants/

And this 'setup.service' file would then execute the command:

curl -sSL https://cloud_drive/setupscript.sh | sh

That way I would stay independent (mostly) from the image build process because I would have to only manage one single file?

At least I like the thought of staying this flexible. And I could write a shell script that's even manually executable...just as usual. Now the question is whether that even works.
Doesn't the system do a file-system-extention after first boot and also restarts after that?

I also want to add some custom deb-packages. Just like it was explained here: https://github.com/ilbers/isar/blob/master/meta-isar/recipes-app/prebuilt-deb/prebuilt-deb_0.1.bb

# This software is a part of ISAR.
# Copyright (c) Siemens AG, 2021
#
# SPDX-License-Identifier: MIT

inherit dpkg-prebuilt

# NOTE: The deb packages should almost never be stored in the repo itself but
#       rather fetched from a binary-serving location. For this example, local
#       storage was just simpler to maintain across all archs and distros.
SRC_URI = "file://example-prebuilt_1.0.0-0_all.deb"

# Only needed if recipe name != package name, as in this case. Or multiple
# packages are provided by a single recipe.
PROVIDES += "example-prebuilt"

==========================

As far as I understand, you have to add the Directory name "prebuilt-deb" (which lies inside of recipes-app) to the IMAGE_INSTALL variable inside of https://github.com/siemens/meta-iot2050/blob/jan/ubuntu/recipes-core/images/iot2050-image-example.bb

If this is correct...what do I need to be aware of? The image build process takes very long, so I really don't want to test each single change with a new build! I also don't think that the explanation above is really that great if you don't already know what they are talking about.

Does the image build process allow debian packages with init.sh files that use systemd for the installation process? Or do I need to custom that deb file so that it creates the links without the need of systemd? I am asking because I red, that the image build process might use only something like a simple chroot environment which doesn't allow the active use of things like systemd.

Thanks for your help!