Error Message: No peer endpoint available to which to send SAML response

Question

I installed Shibboleth SP on my mac. I try to make a connect with the test shib. However, I get this error after I login.

 Error Message: No peer endpoint available to which to send SAML response 

Here's my Shibboleth2.xml

<Sessions lifetime="28800" timeout="3600" relayState="ss:mem"
          checkAddress="false" handlerSSL="false" cookieProps="http">


    <SSO entityID="https://idp.testshib.org/idp/shibboleth"
         discoveryProtocol="SAMLDS" forceAuthn="true">
      SAML2 SAML1
    </SSO>


    <MetadataProvider type="XML" uri="http://www.testshib.org/metadata/testshib-providers.xml"
          backingFilePath="testshib-two-idp-metadata.xml" reloadInterval="180000">
    </MetadataProvider>

here's my metadata

 <md:AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://localhost/Shibboleth.sso/SAML2/POST" index="1"/>
    <md:AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST-SimpleSign" Location="https://localhost/Shibboleth.sso/SAML2/POST-SimpleSign" index="2"/>
    <md:AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:PAOS" Location="https://localhost/Shibboleth.sso/SAML2/ECP" index="3"/>
    <md:AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:browser-post" Location="https://localhost/Shibboleth.sso/SAML/POST" index="4"/>

Why I am getting this error?

Answer 1

This message indicates a mismatch between the configuration of the Testshib Identity Provider and your Shibboleth Service Provider you tried logging in to. I would suspect a problem caused by using the name "localhost" in the Assertion Consumer Service URL provided with your metadata. The IDP is trying to send the SAML response to https://localhost/Shibboleth.sso/SAML2/POST, but there is of course no Assertion Consumer Service because "localhost" is in this case the IDP itself.

So, I would start by removing everything from Testshib, changing your SP's entityID to make it more unique (Use your IP address instead of localhost) and re-add updated metadata for your SP to TestShib.