What to do if Apache won't start?

Question

linux

Apache stopped starting, there is something in the log about the test config, but it is not there!
log:

[email protected]:~# journalctl -xn
-- Logs begin at Пн 2017-06-26 23:05:02 MSK, end at Пн 2017-06-26 23:11:05 MSK. --
июн 26 23:11:05 192.168.0 systemd[1]: Starting LSB: Apache2 web server...
-- Subject: Начинается запуск юнита apache2.service
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Начат процесс запуска юнита apache2.service.
июн 26 23:11:05 192.168.0 apache2[2247]: Starting web server: apache2 failed!
июн 26 23:11:05 192.168.0 apache2[2247]: The apache2 configtest failed. ... (warning).
июн 26 23:11:05 192.168.0 apache2[2247]: Output of config test was:
июн 26 23:11:05 192.168.0 apache2[2247]: AH00534: apache2: Configuration error: No MPM loaded.
июн 26 23:11:05 192.168.0 apache2[2247]: Action 'configtest' failed.
июн 26 23:11:05 192.168.0 apache2[2247]: The Apache error log may have more information.
июн 26 23:11:05 192.168.0 systemd[1]: apache2.service: control process exited, code=exited status=1
июн 26 23:11:05 192.168.0 systemd[1]: Failed to start LSB: Apache2 web server.
-- Subject: Ошибка юнита apache2.service
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Произошел сбой юнита apache2.service.
--
-- Результат: failed.
июн 26 23:11:05 192.168.0 systemd[1]: Unit apache2.service entered failed state.

Answer 1

Somewhere in the apache configuration there is an error.
Look at the errorlog - there may be more information, such as which line.
You specifically have an error with the MPM module - either there are not enough parameters for it, or you upgraded Apache, and the config remains from the old one, in which the options may go in the wrong order (for example, virtualhost blocks before modules loading blocks)
Check the file configuration, you can also google . If everything is bad - post the configs here, then you can be more specific. Because there can be many options that caused the error.

Answer 2

apt-get purge apache2 && apt-get install nginx -y

Answer 3

AH00534: apache2: Configuration error: No MPM loaded.
The Apache error log may have more information.

Answer 4

Action 'configtest' failed.
Indicates that the configuration correctness test has failed. If you run the configtest command in the console, it will tell you where the error is in your configs.