apache2.conf is the wrong file as that is the config file for the normal apache instance. The 389-admin package is trying to run a separate instance of apache, apparently listening on port 9830, which uses a different config file (see the -f argument in the error message), namely:
/etc/dirsrv/admin-serv/httpd.conf
This file includes the other config files in the same directory: admserv.conf, console.conf, nss.conf
Tried to navigate to these files but admin-serv is an empty directory as the ls comand was coming up with nothing.
You must be mistaken, you have accessed the httpd.conf file when you ran the command below (it would fail with 'Could not open configuration file' if the file did not exist):
You might be able to debug the problem by running
/usr/sbin/apache2 -t -f /etc/dirsrv/admin-serv/httpd.conf
which will attempt to check the syntax of specified file.
Gives this output:
AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
(2)No such file or directory: AH02291: Cannot access directory '/var/log/dirsrv/admin-serv/' for main error log
AH00014: Configuration check failed
root@debian:/home/dell#
That's why the 389-admin instance of apache is failing to start: the config file is not valid. You are seeing the same errors as in the Debian bug report. You could follow the bug report and fix the above errors but then I guess you will get to the next error, 'unable to create AdmldapInfo', and I have no idea how to fix that.
389-ds is a redhat project
https://directory.fedoraproject.org/ and the Debian integration appears to be less than ideal. The next version of Debian has a newer version of 389-ds and has dropped 389-admin.
Do you really need the 389-admin instance of apache listening on port 9830? If you only want the standard instance of apache listening on port 80 then I would recommend disabling or removing 389-admin. If you really want the 389-admin instance then you will need to create a valid configuration file. I don't know what such a file would look like, I don't know if the 'setup-ds-admin' script is supposed to create it, and I don't know if the script works on Debian.