...
    <MetadataProvider id="DFN_AAI_eduGAIN"
                  xsi:type="FileBackedHTTPMetadataProvider"
                  backingFile="%{idp.home}/metadata/dfn-aai-edugain+sp-metadata.xml"
                  metadataURL="http://www.aai.dfn.de/metadata/dfn-aai-edugain+sp-metadata.xml"
                  maxRefreshDelay="PT2H">
            <MetadataFilter xsi:type="SignatureValidation" requireSignedRoot="true"
                  certificateFile="/etc/ssl/aai/dfn-aai.pem"/>
            <MetadataFilter xsi:type="Predicate" direction="exclude" removeEmptyEntitiesDescriptors="true" trim="true">
                  <Tag name="http://aai.dfn.de/edugain/registrationAuthority" nameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri">
                       <Value>http://xyz.qq</Value>
                       <Value>http://zyx.ww</Value>
                  </Tag>
            </MetadataFilter>
    </MetadataProvider>
...