'OTD DOES NOT CACHE IF THERE IS NO "LAST-MODIFIED" HEADER' In the Response Header When Using Oracle Traffic Director 11.1.1.7.0 (Doc ID 1995403.1)

Last updated on APRIL 20, 2023

Applies to:

Symptoms

When OTD is configured to use proxy cache the content is not cached if there is no "Last-Modified" header in the response. For example:

You can see that file in the cache is replaced, as a result the cache is not being utilized and the "hits" stay at 0. The expected behavior is for the file to be retrieved from the cache on subsequent requests. This can cause performance degradation. You see the same behavior if "if-modified-since" header is sent with a time that is earlier than the "modified" time in the cache.
 
A note that if a "if-modified-since" header is sent with a time that is later than the "modified" time in the cache you will get a 304 which tells the browser to serve content from it's local cache. This last part is expected behavior.
 
If a "last-modified" header is sent in the response or added via the OTD configuration then the proxy cached behaves as expected. The content is
retrieved from origin server on first request and subsequent requests are retrieved from proxy cache.

Changes

Cause

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