We have just started enabling caching on our Apache 2.2.3 Web Server to take advantage of the performance increase. We use Apache as a proxy to our back end Java applications. One of our larger portal applications has had reports of users logging in and getting other users content. We don't have this problem when we disable the cache so we are somehow caching user specific content sometimes. We don't see this with most users in production, and we are unable to replicate this behavior in test or production at this time.
Does anyone have any ideas what could cause this intermittent caching behavior? I looked at the Change log and found something that could be a possibility, but I don't fully understand this bug. Under 2.2.12 Changes: *) mod_disk_cache/mod_mem_cache: Fix handling of CacheIgnoreHeaders directive to correctly remove headers before storing them. [Lars Eilebrecht] Could it be possible that CacheIgnoreHeaders is sometimes storing a "Set-Cookie" header for content when it shouldn't be? If so, would it be possible that the next request for that content comes with the original requestors cached "Set-Cookie" header and resets the current users Cookie or ID. This could then cause the current user to access the original requestors data since the "Set-Cookie" header might have been accidentally stored in the cache. If this could be the cause does anyone know how I could prove this in test? Here is our current caching configuration using mod_expires, mod_cache, and mod_disk_cache. We are disabling some areas of the site that use velocity because we don't want to cache some of the dynamic stuff like sessionVariable property files for example. Any help is appreciated! Thank you! <IfModule mod_cache.c> <IfModule mod_disk_cache.c> CacheRoot /opt/apache/cache/ CacheEnable disk / # FORCE caching for all requests (without Cache-Control: no-cache) # If Last-Modified header is removed you need to set this to ON to cache CacheIgnoreNoLastMod On CacheDisable /business/sessionVariableSetup.vm CacheDisable /business/education/ CacheDisable /business/partners/ CacheDisable /business/consultants/ CacheDisable /business/home/ CacheIgnoreHeaders Set-Cookie Set-Cookie2 </IfModule> <IfModule mod_expires.c> # Add expires headers for images, css & js files ExpiresActive On ExpiresByType image/gif A28800 ExpiresByType image/jpeg A28800 ExpiresByType image/png A28800 ExpiresByType text/css A28800 ExpiresByType text/javascript A28800 ExpiresByType application/x-javascript A28800 ExpiresByType application/javascript A28800 ExpiresByType application/ecmascript A28800 ExpiresByType image/x-icon A28800 </IfModule> </IfModule> Patrick ________________________________ This communication is the property of Qwest and may contain confidential or privileged information. Unauthorized use of this communication is strictly prohibited and may be unlawful. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy all copies of the communication and any attachments.