Caching does not occur on the following page types:
- Default welcome pages
- Access-protected documents, and pages requested over Secure Sockets Layer (SSL).
Caching limitations exist for the following situations:
- The Cache Accelerator cannot serve GET requests ending in "/" out of the cache.
- The Cache Accelerator supports only limited multilanguage content negotiation.
Caching occurs for only a single language version, where a given URL maps to multiple translated versions.
- The Cache Accelerator listens on all the IP adapters of a server, on the port specified by the Port directive.
You cannot configure the Cache Accelerator to listen on some IP adapters, but not others.
- Caching does not occur on files larger than 64KB.
- The Cache Accelerator does not cache files on, or log to locally mounted remote file systems, like the
Network File System (NFS).
- The Cache Accelerator does not support IP-based virtual host caching. Disable the Cache Accelerator for these directories.
Use the AfpaCache off directive in any IP-based virtual host definitions.
The following operational restrictions apply:
- The IBM HTTP Server Cache Accelerator does not run as a proxy server.
- Cached responses do not return expired headers.
- The IBM HTTP Server access log does not integrate the Cache Accelerator access log.
- When you enable the Cache Accelerator, set the MaxRequestsPerChild
directive to 0, to work around a problem that occurs when
the child process stops and restarts on a loaded Web server.
- Only one active instance of the server can exist while running the Cache Accelerator.
- Do not install the IBM HTTP Server on a machine running the IBM Netfinity Web Server Accelerator.
- Only access logging facilities exist for monitoring the Cache Accelerator.
Support exists for name-based virtual hosts.
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