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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Varnish folks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>How does saint mode work when a director is being used? The discussion here<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-left:.5in'><a href="https://www.varnish-cache.org/trac/wiki/VCLExampleSaintMode">https://www.varnish-cache.org/trac/wiki/VCLExampleSaintMode</a><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p><p class=MsoNormal>mentions this case briefly, but doesn’t have much detail.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>To make this more concrete, let’s say I am using a round-robin director to distribute traffic across three back ends named A, B, and C, and suppose that in vcl_fetch I see a 500 response that came from A. If I set saint mode to 20 seconds on the response, does that mean that the object is blacklisted on A for 20 seconds, and therefore subsequent requests for that object go to B and C? And if saint mode subsequently also blacklists the object on B and C as well, does that mean that grace mode kicks in, and a cached copy is returned?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Assuming I have this right, then it sounds like the backend health checks used by the director are a large-scale way to blacklist all requests for a back end, whereas saint mode is a small-scale object-by-object way to blacklist a back end.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks in advance for the help,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Jeff<o:p></o:p></p></div></body></html>