Embodiments of the present disclosure provide a method for scaling of a server VNF in a virtualized network. The virtualized network comprises at least a server VNF, a client VNF connected to the server VNF and a VNF manager. The connection between the client VNF and the server VNF is initiated by the client VNF. The method is performed at a PCM server. Firstly, scaling information is obtained at the PCM server in response to a scaling operation performed by the VNF manager on the server VNF. Once the scaling information is obtained, then the PCM server notifies the client VNF of the scaling information. There is also provided a method performed at a client VNF and corresponding apparatuses.