500 error when accessing /cpanel, /webmail and /whm redirects.

Symptoms

When accessing /cpanel, /webmail, and /whm redirects I receive a 500 error. The following error is output via the Apache error_log:

AH01215: /usr/local/cpanel/3rdparty/bin/perl: error while loading shared libraries: libperl.so: failed to map segment from shared object: Cannot allocate memory: /usr/local/cpanel/cgi-sys/redirect.cgi

Description 

The issue is caused by Apache's Memory Usage Restrictions being set too low. This module can be found in WHM's Apache Configuration module.

Workaround

Increase or disable the "RLimitMEM" limit within the Apache Configuration:

1. Log into WHM as the root user.
2. Navigate to "Home / Service Configuration / Apache Configuration / Memory Usage Restrictions."
3. Increase or disable the "RLimitMEM" setting.
4. Click Save.