I am now one step further…
### CREATING SITE 'cmk'
Adding /opt/omd/sites/cmk/tmp to /etc/fstab.
Going to set TMPFS to off.
Temporary filesystem already mounted
Updating core configuration...
Generating configuration for core (type nagios)...Precompiling host checks...OK
OK
Executing post-create script "01_create-sample-config.py"...OK
Created new site cmk with version 2.0.0p8.cre.
The site can be started with omd start cmk.
The default web UI is available at http://d263d224804f/cmk/
The admin user for the web applications is cmkadmin with password: c5JXynPC
For command line administration of the site, log in with 'omd su cmk'.
After logging in, you can change the password for cmkadmin with 'htpasswd etc/htpasswd cmkadmin'.
### STARTING XINETD
[ ok ] Starting internet superserver: xinetd.
### STARTING SITE
Temporary filesystem already mounted
Starting mkeventd...OK
Starting rrdcached...OK
Starting npcd...OK
Starting nagios...OK
Starting apache...OK
Starting redis...OK
Initializing Crontab.../var/spool/cron/: mkstemp: Permission denied
Exception ignored in: <_io.TextIOWrapper name='<stdout>' mode='w' encoding='utf-8'>
BrokenPipeError: [Errno 32] Broken pipe
ERROR
Here I found the following recommendation for this problem: Problem with check-mk-raw:2.0.0b6 - "Initializing Crontab.../var/spool/cron/: mkstemp: Permission denied"
but it’s not applicable, any other tip’s ?