'Starts a replication between volumes.
Requires the dvolume to be in an appropriate state to start this.
:param svolume: Source SC Volume.
:param dvolume: Destiation SC Volume
:param replicationtype: Asynchronous or synchronous.
:param qosnode: QOS node name.
:param activereplay: Boolean to replicate the active replay or not.
:return: ScReplication object or None.'

def start_replication(self, svolume, dvolume, replicationtype, qosnode, activereplay):

    if (svolume and dvolume):
        qos = self._find_qos(qosnode, svolume['scSerialNumber'])
        if qos:
            payload = {}
            payload['QosNode'] = self._get_id(qos)
            payload['SourceVolume'] = self._get_id(svolume)
            payload['StorageCenter'] = svolume['scSerialNumber']
            payload['ReplicateActiveReplay'] = activereplay
            payload['Type'] = replicationtype
            payload['DestinationVolume'] = self._get_id(dvolume)
            payload['DestinationStorageCenter'] = dvolume['scSerialNumber']
            r = self.client.post('StorageCenter/ScReplication', payload, True)
            if self._check_result(r):
                LOG.info('Replication    created    for    %(src)s    to    %(dest)s', {'src': svolume.get('name'), 'dest': dvolume.get('name')})
                screpl = self._get_json(r)
                return screpl
    return None
