Could not connect physical network device by NETCONF

Hi all,

I want to connect physical network device by NETCONF in OpenDaylight. The physical network device is mx5, and I use the Boron. I refer this URL. http://docs.opendaylight.org/en/stable-boron/user-guide/netconf-user-guide.html

I issued the following API to establish NETCONF connection, and no errors outputed.

curl --user "admin":"admin" -H "Accept: application/xml" -H "Content-type: application/xml" -X POST http://localhost:8181/restconf/config/network-topology:network-topology/topology/topology-netconf/node/controller-config/yang-ext:mount/config:modules -d '
<module xmlns="urn:opendaylight:params:xml:ns:yang:controller:config">
  <type xmlns:prefix="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">prefix:sal-netconf-connector</type>
  <name>mx5-1</name>
  <address xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">device address</address>
  <port xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">22</port>
  <username xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">admin</username>
  <password xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">password</password>
  <yang-module-capabilities xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">
    <capability xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:connector:netconf">
      urn:ietf:params:xml:ns:yang:ietf-inet-types?module=ietf-inet-types&revision=2010-09-24
    </capability>
  </yang-module-capabilities>
  ...

As long as watching network topology, it seemd to succeed in connection.

curl -u admin:admin -H "Content-Type: application/json" -X GET http://172.26.201.109:8181/restconf/operational/network-topology:network-topology/topology/topology-netconf/node/mx5-1/ -s | python -m json.tool
{
    "node": [
        {
            "netconf-node-topology:available-capabilities": {
                "available-capability": [
                    "http://xml.juniper.net/netconf/junos/1.0",
                    "urn:ietf:params:xml:ns:netconf:capability:candidate:1.0",
                    "urn:ietf:params:netconf:capability:confirmed-commit:1.0",
                    "http://xml.juniper.net/dmi/system/1.0",
                    "urn:ietf:params:netconf:capability:url:1.0?scheme=http,ftp,file",
                    "urn:ietf:params:netconf:capability:candidate:1.0",
                    "urn:ietf:params:xml:ns:netconf:capability:confirmed-commit:1.0",
                    "urn:ietf:params:netconf:capability:validate:1.0",
                    "urn:ietf:params:xml:ns:netconf:base:1.0",
                    "urn:ietf:params:xml:ns:netconf:capability:url:1.0?protocol=http,ftp,file",
                    "(urn:ietf:params:xml:ns:yang:ietf-inet-types?revision=2010-09-24)ietf-inet-types",
                    "urn:ietf:params:xml:ns:netconf:capability:validate:1.0",
                    "urn:ietf:params:netconf:base:1.0"
                ]
            },
            "netconf-node-topology:connection-status": "connected",
            "netconf-node-topology:host": "172.26.218.237",
            "netconf-node-topology:port": 830,
            "netconf-node-topology:unavailable-capabilities": {},
            "node-id": "mx5-1"
        }
    ]
}

But, when I issued the API to get the configulation of the physical network device, an error occuered.

curl -u admin:admin -H "Content-Type: application/json" -X GET http://localhost:8181/restconf/config/network-topology:network-topology/topology/topology-netconf/node/mx5-1/yang-ext:mount -s | python -m json.tool
{
    "errors": {
        "error": [
            {
                "error-message": "Request could not be completed because the relevant data model content does not exist ",
                "error-tag": "data-missing",
                "error-type": "application"
            }
        ]
    }
}

Warnings were outputed in log of the OpenDaylight.

2016-12-27 15:18:58,842 | WARN  | oupCloseable-3-2 | NetconfDeviceCommunicator        | 302 - org.opendaylight.netconf.sal-netconf-connector - 1.4.1.Boron-SR1 | RemoteDevice{mx5-1}: Session terminated Session closed
2016-12-27 15:18:58,859 | WARN  | oupCloseable-3-2 | ReadOnlyTx                       | 302 ...