InstanceIdentifier<VpnInstance1> id = InstanceIdentifier.builder(VpnInstances.class)
.child(VpnInstance.class, new VpnInstanceKey(vpnName)).augmentation(VpnInstance1.class).build();
Optional<VpnInstance1> vpnInstance = read(LogicalDatastoreType.OPERATIONAL, id);
InstanceIdentifier<VpnInstance1> id = InstanceIdentifier.builder(VpnInstances.class)
.child(VpnInstance.class, new VpnInstanceKey(vpnName)).augmentation(VpnInstance1.class).build();
Optional<VpnInstance1> vpnInstance = read(LogicalDatastoreType.OPERATIONAL, id);