Methods, systems and apparatus for handling maintenance events in public cloud deployments

A method of implementing a real time communications service comprising:

• receiving, by a maintenance management application of a real time communications service, a first maintenance notification indicating a first virtual machine is to undergo a first maintenance event;
• determining, by the maintenance management application, a first Packet Front End application of the real time communications service executing on the first virtual machine;
• determining, by the maintenance management application, public Internet Protocol (IP) addresses being hosted by the first Packet Front End application;
• notifying, by the maintenance management application, session control applications of the real time communications service to drain the determined public IP addresses being hosted by the first Packet Front End application;
• in response to receiving the first maintenance notification indicating the first virtual machine is to undergo a first maintenance event, monitoring by the maintenance management application, the status of the first Packet Front End application determined to being executing on the first virtual machine;
• and
• upon detecting that the first Packet Front end application has terminated operation, notifying all session control applications of the real time communications service that notifications pertaining to the public IP addresses hosted by the first Packet Front End application are no longer valid.

A Public Cloud system comprising:

• a plurality of servers, said plurality of servers including a first server on which a first virtual machine is implemented, a maintenance management application of a real time communications service executing on the first virtual machine, said maintenance management application performing the following operations:
• receiving, from a Public Cloud maintenance and management entity of the Public Cloud system, a first maintenance notification indicating a second virtual machine located on a second server of the plurality of servers is to undergo a first maintenance event, said Public Cloud system being used to implement the real time communications service, said Public Cloud maintenance and management entity managing the maintenance of applications, virtual machines, and servers in the Public Cloud system;
• determining a first Packet Front End application of the real time communications service is executing on the second virtual machine;
• determining public Internet Protocol (IP) addresses being hosted by the first Packet Front End application;
• and
• notifying session control applications of the real time communications service to drain the determined public IP addresses being hosted by the first Packet Front End application;
• wherein in response to receiving a notification to drain a public IP address corresponding to a media IP address, each session control application of the real time communications service stops using the public IP address in Session Description Protocol offer and answer messages for new dialogs;
• and
• wherein in response to receiving a notification to drain a public IP address corresponding to a signaling IP address, each session control application of the real time communications service upon receiving an initial dialog request from a signaling IP address for which a drain notification was received, populates a Contact header of a reply message with a signaling IP address for which no draining notification has been received.

A non-transitory machine readable medium including a first set of executable instructions forming a maintenance management application of a real time communications service which when executed by a processor of a first server in a Public Cloud system cause the first server to perform the following operations:

• receiving, from a Public Cloud maintenance and management entity of the Public Cloud system, a first maintenance notification indicating a first virtual machine located on a second server in the Public Cloud system is to undergo a first maintenance event, said Public Cloud system being used to implement the real time communications service, said Public Cloud maintenance and management entity managing the maintenance of applications, virtual machines, and servers of the Public Cloud system;
• determining a first Packet Front End application of the real time communications service is executing on the first virtual machine;
• determining public Internet Protocol (IP) addresses being hosted by the first Packet Front End application;
• notifying session control applications of the real time communications service to drain the determined public IP addresses being hosted by the first Packet Front End application;
• in response to receiving the first maintenance notification indicating the first virtual machine is to undergo a first maintenance event, monitoring by the maintenance management application, the status of the first Packet Front End application determined to being executing on the first virtual machine;
• and
• upon detecting that the first Packet Front end application has terminated operation, notifying all session control applications of the real time communications service that notifications pertaining to the public IP addresses hosted by the first Packet Front End application are no longer valid.

A Public Cloud system comprising:

• a plurality of servers, said plurality of servers including a first server on which a first virtual machine is implemented, a maintenance management application of a real time communications service executing on the first virtual machine, said maintenance management application performing the following operations:
• receiving, from a Public Cloud maintenance and management entity of the Public Cloud system, a first maintenance notification indicating a second virtual machine located on a second server of the plurality of servers is to undergo a first maintenance event, said Public Cloud system being used to implement the real time communications service, said Public Cloud maintenance and management entity managing the maintenance of applications, virtual machines, and servers in the Public Cloud system;
• determining a first Packet Front End application of the real time communications service is executing on the second virtual machine;
• determining public Internet Protocol (IP) addresses being hosted by the first Packet Front End application;
• notifying session control applications of the real time communications service to drain the determined public IP addresses being hosted by the first Packet Front End application;
• in response to receiving the first maintenance notification indicating the second virtual machine is to undergo a first maintenance event, monitoring by the maintenance management application, the status of the first Packet Front End application determined to being executing on the second virtual machine;
• and
• upon detecting that the first Packet Front end application has terminated operation, notifying all session control applications of the real time communications service that notifications pertaining to the public IP addresses hosted by the first Packet Front End application are no longer valid.