How to safely purge in Varnish if backend is sick without losing content

Posted by Highway of Life on Stack Overflow See other posts from Stack Overflow or by Highway of Life
Published on 2013-11-01T03:49:49Z Indexed on 2013/11/01 3:53 UTC
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purge

If the backend is sick, what is the preferable way to ensure that stale content can be retrieved from the backend when a PURGE request is made?

When a PURGE request is made, whether or not the backend is sick, by default the content will be eliminated from the Varnish cache and if the backend is down, a 503 page would be served to the user until the backend comes back online to serve a new version of the content. I'd like to be able to at least serve up a stale version of the content if a new version could not be retrieved from the backend.

Is this possible without installing the Softpurge Varnish Mod?

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