xsrv VS DietPi

Yes, OpenLDAP installed from this ansible role

It's dead easy to use TCP/SSL instead of UDP to forward logs. Example rsyslog config

I use rsyslog for that since it's the default in Debian. Configuring forwarding is very simple, a single file in /etc/rsyslog.d/forwarding.conf [1]. Note that this setup uses TLS to encrypt messages so you need to create the relevant certificates (I use self-signed certs). Unencrypted TCP or UDP is simpler, but less secure.

preseed.cfg contains a few basic options needed to setup the OS [1]

I do this with https://github.com/nodiscc/xsrv/tree/master/roles/openldap + https://github.com/nodiscc/xsrv/tree/master/roles/samba. It's just a standalone samba server + LDAP auth for users, no DC or anything like that, so I'm not sure this is what you're looking for.

This ansible role (check the tasks/ directory) gives a good breakdown of what is needed to setup a basic LDAP server and authentication service

I use samba in standalone mode with or without LDAP auth https://github.com/nodiscc/xsrv/tree/master/roles/samba

DietPi is a lightweight Debian based Linux distribution for SBCs and server systems, with the option to install desktop environments, too. It ships as minimal image but allows to install complete and ready-to-use software stacks with a set of console based shell dialogs and scripts.

The source code is hosted on GitHub: https://github.com/MichaIng/DietPi

That's a good point, but the array of devices supported by the DietPi team is extensive: https://dietpi.com/

Before someone starts the usual yadda yadda about the RPi biger community, the OS not having long time support etc. I would repeat one more time: do not rely on board vendor supplied images; this is valid for pretty much all boards. Just go to Armbian or DietPi pages and you'll almost certainly find one or more images that work on your board and forums to discuss about them with very knowledgeable people.

https://www.armbian.com/download/

https://dietpi.com/#download

Those projects are well worth a contribution, as they don't have a giant like Broadcom behind them.

> bananapi do a lot of boards but their software story has been a bit poor

This is quite common with other board manufacturers too. I'd rather suggest to ignore completely their cobbled together distros, often also tainted by proprietary modifications, that become unmaintained in a few years, and see if they're among the many supported by Armbian or DietPi.

https://www.armbian.com/download/

https://dietpi.com/#download

The full release notes can be found at: https://dietpi.com/docs/releases/v8_25/

RPi OS = diet pi https://dietpi.com/ - initial config via text file - SDcard burning out partially mitigated as writes log files to ram then flushes to SDcard reducing write cycles

You could also try very minimalistic distros like TwisterUI or DietPi which are most known for their use in the RasprebbyPi / SBC computers but which also have editions for desktop / laptop.