Software version maintenance in a software defined network

A computer program product comprising:

• one or more computer readable storage media and program instructions stored on the one or more computer readable storage media, the program instructions comprising instructions to:
• identify, by a software defined networking controller (SDN controller), an element managed by the SDN controller on which to perform a software version maintenance operation, the identified element in a software defined network (SDN), wherein identifying the element comprises:
• responsive to the SDN controller determining that the element has powered up, sending a vendor packet from the SDN controller to the element;
• receiving a reply to the vendor packet from the element, the reply identifying a version of a software image installed on the element, the reply identifying an element type for the element selected from a list consisting of a network switch, a router, a VPN, a firewall, a hypervisor, an agent, and appliance, and a load balancer;
• determining, using the SDN controller, that the version identified in the reply does not match a required version of the software image identified in a catalog maintained by the SDN controller;
• ensure, using the SDN controller, that there is an active backup for the element in the SDN;
• responsive to ensuring that there is an active backup for the element, de-activate, using the SDN controller, the element;
• initiate the software version maintenance operation on the element;
• and
• in response to completion of the software version maintenance operation, re-activate, using the SDN controller, the element in the SDN.

A computer system comprising:

• one or more computer processors;
• one or more computer readable storage media;
• program instructions stored on the computer readable storage media for execution by at least one of the computer processors, the program instructions comprising instructions to:
• identify, by a software defined networking controller (SDN controller), an element managed by the SDN controller on which to perform a software version maintenance operation, the identified element in a software defined network (SDN), wherein identifying the element comprises:
• responsive to the SDN controller determining that the element has powered up, sending a vendor packet from the SDN controller to the element;
• receiving a reply to the vendor packet from the element, the reply identifying a version of a software image installed on the element, the reply identifying an element type for the element selected from a list consisting of a network switch, a router, a VPN, a firewall, a hypervisor, an agent, and appliance, and a load balancer;
• determining, using the SDN controller, that the version identified in the reply does not match a required version of the software image identified in a catalog maintained by the SDN controller;
• ensure, using the SDN controller, that there is an active backup for the element in the SDN;
• responsive to ensuring that there is an active backup for the element, de-activate, using the SDN controller, the element;
• initiate the software version maintenance operation on the element;
• and
• in response to completion of the software version maintenance operation, re-activate using the SDN controller, the element in the SDN.