ref. to Igor: I think the system runs fine because i can ping and because there is actually a ssh server active. Due to that I have a Odroid HC2 and not the XU4, I have no console and have to rely on ssh. I used putty and the ssh client in the "advanced IP scanner" - www.advanced-ip-scanner.com: both seem to connect but 1234 just does not work. In that Debian raspberry I used the normal ssh client and in WIN10/11 also the ssh client from the command line. All of these three ssh clients were not able to connect to the Odroid due to a different level of keystrength and procedure. I try the WIN11 ssh client to accept the situation and will come back

Might be because at first login, you enter 1234, it then asks for you to change that, create a user and whatnot. Not so sure putty will have any idea of what to do with those prompts. When you wrote: "once more: tried ssh through a raspi in the network. the raspi cannot connect to the armbian:" What do you mean by that? You logged in to a rpi OS with putty, and you then tried to connect to this device via the rpi? Was this before or AFTER you already tried logging in to it using putty? In your log: ### [firstrun] Recreated SSH keys (entropy: 256 256) I don't know what this means, but sounds like keys are enrolled and maybe assumed to be used in future. You will have to look into putty (and ask the devs of putty) to learn what is happening, unless you are willing to use a "normal" ssh client that will tell you what is going on by providing STDOUT & STDERR to your monitor. With a NORMAL ssh client, type "ssh root@xxx.xxx.xxx.xxx" (the ip to the device) and it will ask for passw, it will then require you to CHANGE passwd etc. Seems very likely putty has no idea how to deal with that and are doing some strange things at first login, witch then probably leads to it borking your system.

Is it possible to build against a current kernel (6.18 for example)? I am trying to build an access point on Armbian but 6.6 does not support AP mode on most adapters.

ok thanks.

Moved to off-topic as this isn't Armbian related