Cobra Forum

Question: Unable to start Apache web server on a Plesk server: AH02093: mod_watchdog is required


Applicable to:

• Plesk for Linux

Symptoms

• Websites fail to load with one of the following error messages in a web browser:

502 Bad Gateway
ERR_CONNECTION_REFUSED

• Apache service fails to start or is in reloading status.
• The following error messages are logged in /var/log/httpd/error_log:

AH03262: mod_watchdog is required
AH00020: Configuration Failed, exiting

Cause

Module mod_watchdog required by Apache is disabled on the server.


Resolution

Plesk interface

1.Log in to Plesk.

2.Go to Tools & Settings > Apache & nginx Settings.

3.In Apache modules section, turn on watchdog module.

4.Apply the changes.


Command-line interface

1.Connect to your Plesk server via SSH.

2.Open the file /etc/httpd/conf.modules.d/00-base.conf in a text editor. In this example, we are using vi editor:

# vi /etc/httpd/conf.modules.d/00-base.conf

3.Find the line with watchdog_module and uncomment it:
Before:

;LoadModule watchdog_module modules/mod_watchdog.so
After:

LoadModule watchdog_module modules/mod_watchdog.so
4.Save the changes and close the file.

5.Restart the Apache service:

# service httpd restart