Hi, I upgraded from debian 7 to 8 (yeah - quite late) and so from apache2.4 to 2.4, before i go for debian 9 I need some help for this issue:

when I start apache I get this:

Nov 14 15:20:32 srv087 apache2[27920]: Starting web server: apache2 failed!
Nov 14 15:20:32 srv087 apache2[27920]: The apache2 instance did not start within 20 seconds. Please read the log files to discover problems ... (warning).
Nov 14 15:20:32 srv087 systemd[1]: apache2.service: control process exited, code=exited status=1
Nov 14 15:20:32 srv087 systemd[1]: Failed to start LSB: Apache2 web server.
Nov 14 15:20:32 srv087 systemd[1]: Unit apache2.service entered failed state.

but the server with the ID is running:

   27934	root	15:20	/usr/sbin/apache2 -k start
      27937	www-data	15:20	/usr/sbin/apache2 -k start
      27938	www-data	15:20	/usr/sbin/apache2 -k start
      27939	www-data	15:20	/usr/sbin/apache2 -k start

in the error log I get this:

[Wed Nov 14 15:20:12.229256 2018] [core:warn] [pid 27934] AH00098: pid file /var/run/apache2.pid overwritten -- Unclean shutdown of previous Apache run?
[Wed Nov 14 15:20:12.235164 2018] [mpm_prefork:notice] [pid 27934] AH00163: Apache/2.4.10 (Debian) OpenSSL/1.0.1t configured -- resuming normal operations
[Wed Nov 14 15:20:12.235224 2018] [core:notice] [pid 27934] AH00094: Command line: '/usr/sbin/apache2'

I would like to have apache in normal state ... , any suggestions?

Does this also happen after Apache stop and start (instead of reload/restart)?

Yep

root@srvxx /var/www
$ /etc/init.d/apache2 stop
[ ok ] Stopping apache2 (via systemctl): apache2.service.

root@srvxx /var/www
$ /etc/init.d/apache2 start
[....] Starting apache2 (via systemctl): apache2.serviceJob for apache2.service failed. See 'systemctl status apache2.service' and 'journalctl -xn' for details.
 failed!

root@srvxx/var/www

 

And output of journalctl -xn?

-- Logs begin at Thu 2018-11-08 15:31:09 CET, end at Wed 2018-11-14 16:14:11 CET. --
Nov 14 16:13:38 srvxx dovecot[30185]: lda(root): msgid=<20181114145503.7359F21E0270@ssrvxx>: save failed to INBOX: Read-only mbox
Nov 14 16:13:38 srvxx postfix/local[30184]: 7359F21E0270: to=<root@srvxx>, orig_to=<root>, relay=local, delay=1116, delays=1115/0.01/0/0.16, dsn=4.3.0, status=deferred (temporary failure)
Nov 14 16:13:45 srvxxsrvxxsrvxx systemd[1]: Stopped LSB: Apache2 web server.
-- Subject: Unit apache2.service has finished shutting down
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit apache2.service has finished shutting down.
Nov 14 16:13:51 srvxx systemd[1]: Starting LSB: Apache2 web server...
-- Subject: Unit apache2.service has begun with start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit apache2.service has begun starting up.
Nov 14 16:13:51 srvxx apache2[30226]: Starting web server: apache2httpd (pid 29324) already running
Nov 14 16:14:11 srvxx apache2[30226]: failed!
Nov 14 16:14:11 srvxx apache2[30226]: The apache2 instance did not start within 20 seconds. Please read the log files to discover problems ... (warning).
Nov 14 16:14:11 srvxxsrvxx systemd[1]: apache2.service: control process exited, code=exited status=1
Nov 14 16:14:11 srvxx systemd[1]: Failed to start LSB: Apache2 web server.
-- Subject: Unit apache2.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit apache2.service has failed.
--
-- The result is failed.
Nov 14 16:14:11 srv087 systemd[1]: Unit apache2.service entered failed state.

 

I had to change the lockfile settings from default  

/var/lock/apache2/accept.lock

to
Mutex file:${APACHE_LOCK_DIR} default.

With the original setting apache wouldn't start

Might be there is an error in the mutex configuration which is

# Since there is no sane way to get the parsed apache2 config in scripts, some
# settings are defined via environment variables and then used in apache2ctl,
# /etc/init.d/apache2, /etc/logrotate.d/apache2, etc.
export APACHE_RUN_USER=www-data
export APACHE_RUN_GROUP=www-data
# temporary state file location. This might be changed to /run in Wheezy+1
export APACHE_PID_FILE=/var/run/apache2/apache2$SUFFIX.pid
export APACHE_RUN_DIR=/var/run/apache2$SUFFIX
export APACHE_LOCK_DIR=/var/lock/apache2$SUFFIX
# Only /var/log/apache2 is handled by /etc/logrotate.d/apache2.
export APACHE_LOG_DIR=/var/log/apache2$SUFFIX

any helpful hints are appreciated....

Maybe some issues in the upgrade process? Froxlor does not do anything to init.d-scripts

solved 

changed in envars

export APACHE_PID_FILE=/var/run/apache2$SUFFIX.pid

into:

export APACHE_PID_FILE=/var/run/apache2/apache2$SUFFIX.pid