Apache 2.2.0 is major release of the Apache httpd server and includes a number of critical changes. Many of these changes are improvements of existing modules, but there are also a number of new modules and improvements in some aspects of the operational functionality. This article will cover some of the specific elements that have changed (with examples and alternative configurations) as well as discuss when to upgrade to the new version and when to wait for a future revision.
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As a note, Apache 2.2.0 is available in Cooker...