POST http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1

Payload:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<group xmlns="urn:opendaylight:flow:inventory">
<barrier>false</barrier>
<group-id>1</group-id>
<group-name>Foo</group-name>
</group>

"error": [
{
"error-type": "protocol",
"error-tag": "data-exists",
"error-message": "Data already exists for path: /(urn:opendaylight:inventory?revision=2013-08-19)nodes/node/node[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:1}

]/AugmentationIdentifier

{childNames=[(urn:opendaylight:flow:inventory?revision=2013-08-19)table, (urn:opendaylight:flow:inventory?revision=2013-08-19)ip-address, (urn:opendaylight:flow:inventory?revision=2013-08-19)switch-features, (urn:opendaylight:flow:inventory?revision=2013-08-19)serial-number, (urn:opendaylight:flow:inventory?revision=2013-08-19)hardware, (urn:opendaylight:flow:inventory?revision=2013-08-19)group, (urn:opendaylight:flow:inventory?revision=2013-08-19)software, (urn:opendaylight:flow:inventory?revision=2013-08-19)supported-actions, (urn:opendaylight:flow:inventory?revision=2013-08-19)supported-match-types, (urn:opendaylight:flow:inventory?revision=2013-08-19)description, (urn:opendaylight:flow:inventory?revision=2013-08-19)supported-instructions, (urn:opendaylight:flow:inventory?revision=2013-08-19)meter, (urn:opendaylight:flow:inventory?revision=2013-08-19)manufacturer]}

"
}
]