When sending the following restconf request to ODL, it looks like the parser is stripping off the second xmlns attribute.  

Post request: 

http://<ODL-Server>:8181/restconf/operations/network-topology:network-topology/topology/topology-netconf/node/<Device>/yang-ext:mount/tailf-actions:action/input/

<action xmlns="http://tail-f.com/ns/netconf/actions/1.0">
<data>
<hw-module xmlns="http://www.cisco.com/ns/yang/Cisco-IOS-XR-sysadmin-hw-module">
<oper>
<location>
<location>all</location>
<actions>
<reload/>
</actions>
</location>
</oper>
</hw-module>
</data>
</action>

When checking the ODL logs seeing it removes the second xmlns.

request: <rpc message-id="m-1408" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">

<action xmlns="http://tail-f.com/ns/netconf/actions/1.0">

<data>

    <hw-module>

      <oper>

        <location>

          <location>all</location>

          <actions>

            <reload/>

          </actions>

        </location>

      </oper>

    </hw-module>

  </data>

</action>

</rpc>

The following raw netconf-yang rpc works:

<rpc message-id="edcfd773-daac-4fdd-9867-053d4742d453" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <data>
    <hw-module xmlns="http://www.cisco.com/ns/yang/Cisco-IOS-XR-sysadmin-hw-module">
      <oper>
        <location>
          <location>all</location>
          <actions>
            <reload/>
          </actions>
        </location>
      </oper>
    </hw-module>
  </data>
</action>
</rpc> 

In the yang file the input rpc action is defined as:

  rpc action {

    description

      "Support Tail-F actions rpc format.";

 

    reference "RFC 6241, Section 7.1";

 

    input

Unknown macro: {       anyxml data Unknown macro}

    }