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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Thanks Marvin,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">That info is helpful for us.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">We have seen a spike in the memcached timeout and retrieval errors in the past 2 days. I assume those translate to a failed node. It has been wildly intermittent
and I am struggling to find out if it is network latency or something else.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">I have to believe that 2s is plenty of time for a memcached operation, and I don’t want to mitigate this by simply increasing the timeout allowance.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Thanks again.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Josh<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> users [mailto:users-bounces@shibboleth.net]
<b>On Behalf Of </b>Marvin Addison<br>
<b>Sent:</b> Thursday, August 24, 2017 7:48 AM<br>
<b>To:</b> Shib Users <users@shibboleth.net><br>
<b>Subject:</b> Re: MemcachedStorage and IdP3<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Aug 23, 2017 at 2:48 PM O'Dowd, Josh <<a href="mailto:Josh.O%27Dowd@mso.umt.edu">Josh.O'Dowd@mso.umt.edu</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Basically, I am trying to figure out if a session is lost when Idp tries to retrieve it from a now
unavailable(timing out) node</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">That's what happens. If the node holding the IdPSession object goes down, it has the same effect as if the IdP session were terminated and the user will have to log in again.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I intend to scratch my own itch in coming months and write an IdP storage backend for Redis to provide better resiliency in the case you described. For us the memcached behavior has been tolerable since our memcached daemons have uptimes
measured in months if not years, but we can do better with a key-value store that has replication built in. Hazelcast is similar; I believe there's an IdP component for that technology today (Unicon developed it IIRC).<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">M<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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