Name
ie_refresh
Synopsis
In Section 9.2, I
explained that Internet Explorer versions prior to 5.5 SP1 have a
bug that make it unable to force a validation of cached responses when
using HTTP interception. This directive provides a partial workaround
for the bug. When enabled, Squid pretends that the request contains a
no-cache
directive. Thus, Squid
always forwards these requests on to the origin server or a
neighbor.
Note this affects only requests that meet the following requirements:
The
User-Agent
header indicates Internet Explorer Version 3, 4, 5.0, or 5.01.The
If-Modified-Since
header is present.The request contains a partial URI because it was intercepted (see Chapter 9) or Squid is a surrogate (see Chapter 15).
Squid versions prior to 2.5.STABLE3 contain a bug related to
this feature. Although Squid behaves as though the client’s request
contains a no-cache
directive, it
doesn’t add that directive to the outgoing request. This is a problem
if you have one or more neighbor caches. Because the request received
by the neighbor doesn’t contain a no-cache
directive, it may decide to return
a cache hit, rather than forward it on to the origin server.
Later versions include the no-cache
directive so that such requests
should always reach the origin server.
Syntax | ie_refresh on|off |
Default | ie_refresh off |
Example | ie_refresh on |
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