<div dir="ltr">Thanks for the help Scott and Peter!  I think my issue was more of an Apache config one than Shibboleth.  I created different VirtualHosts for each subdomain so I could reuse the Location value but vary the entityID.  This seems to work for me now:<div>

<br></div><div>NameVirtualHost *:443<br></div><div><div>&lt;VirtualHost *:443&gt;</div><div>  ServerName <a href="https://a.example.com:443">https://a.example.com:443</a></div><div>  &lt;Location /login&gt;</div><div>    AuthType shibboleth</div>

<div>    ShibRequestSetting requireSession On</div><div>    ShibRequestSetting entityID <a href="https://idp1.example.com/idp/shibboleth">https://idp1.example.com/idp/shibboleth</a></div><div>    require valid-user</div>
<div>
  &lt;/Location&gt;</div><div>  ...</div><div>&lt;/VirtualHost&gt;</div></div><div><div><div>&lt;VirtualHost *:443&gt;</div><div>  ServerName <a href="https://b.example.com:443">https://b.example.com:443</a></div><div>  &lt;Location /login&gt;</div>

<div>    AuthType shibboleth</div><div>    ShibRequestSetting requireSession On</div><div>    ShibRequestSetting entityID <a href="https://idp2.example.com/idp/shibboleth">https://idp2.example.com/idp/shibboleth</a></div>

<div>    require valid-user</div><div>  &lt;/Location&gt;</div><div>  ...</div><div>&lt;/VirtualHost&gt;</div></div></div><div><br></div><div><br></div><div>Ted</div><div><br></div></div><div class="gmail_extra"><br><br>
<div class="gmail_quote">
On Thu, Mar 20, 2014 at 10:27 AM, Peter Schober <span dir="ltr">&lt;<a href="mailto:peter.schober@univie.ac.at" target="_blank">peter.schober@univie.ac.at</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">

* Peter Schober &lt;<a href="mailto:peter.schober@univie.ac.at">peter.schober@univie.ac.at</a>&gt; [2014-03-20 15:26]:<br>
<div class="">&gt; I guess &quot;requireSessionWith &lt;IDP-entityID&gt;&quot; is what you want, then.<br>
&gt; <a href="https://wiki.shibboleth.net/confluence/display/SHIB2/NativeSPContentSettings" target="_blank">https://wiki.shibboleth.net/confluence/display/SHIB2/NativeSPContentSettings</a><br>
<br>
</div>Sorry, entityID, like Scott already said.<br>
<div class="HOEnZb"><div class="h5">-peter<br>
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