Method and system for achieving high availability of a primary network controller in a network controller cluster using distributed network device state information

A non-transitory computer readable medium comprising instructions that, when executed by a processor on a network controller, perform a method, the method comprising:

• obtaining, by the network controller in a network controller cluster, network device state information (NDSI) from each network device of a plurality of network devices managed by the network controller cluster, wherein the network controller has a role of a non-primary network controller in the network controller cluster;
• storing the NDSI in a configuration file;
• and
• after the storing:
• receiving a notification that a second network controller in the network controller cluster has failed, wherein the second network controller has a role of primary network controller in the network controller cluster;
• in response to the notification, making a first determination that a role of the network controller has changed to primary network controller in the network controller cluster;
• based on the first determination, loading the NDSI from the configuration file into a network controller state database on the network controller;
• and
• after the loading, initiating operation of the network controller using the network controller state database.

A method for managing a network controller, the method comprising:

• obtaining, by the network controller of a plurality of network controllers in a network controller cluster, network device state information (NDSI) from a network device of a plurality of network devices, wherein the network controller has a role of a non-primary network controller in the network controller cluster and a second network controller in the network controller cluster has a role of primary network controller;
• storing the NDSI in a configuration file on the network controller;
• after the storing:
• making a first determination that a role of the network controller has changed to primary network controller in the network controller cluster;
• based on the first determination, loading the NDSI from the configuration file into a network controller state database on the network controller, wherein the configuration file specifies that the network device was synchronized to the second network controller;
• and
• initiating, after the loading, operation of the network controller using the network controller state database.