Symptoms
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Apache service fails to start or the websites fail to load with:
502 Bad Gateway
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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 is disabled on the server, by required by Apache.
Resolution
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Go to Tools & Setings > Apache Web Server.
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Enable the watchdog module:
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Click OK to apply the changes.
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Connect the Plesk server via SSH.
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Open /etc/httpd/conf.modules.d/00-base.conf in a text editor.In this example, we are using the vi editor:
# vi /etc/httpd/conf.modules.d/00-base.conf
- 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
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Save the changes and close the file.
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Restart the Apache service:
# service httpd restart