Active-active data center using RHI, BGP, and IGP anycast for disaster recovery and load distribution

In a data center topology having a plurality of data centers with each data center comprising at least a server cluster, a method for load balancing and managing traffic flow between at least two active data centers, the method comprising:

• providing a plurality of application services at server clusters at each of the at least two data centers;
• redistributing IGP routes into BGP at the at least two data centers;
• directing traffic to said data centers using an IP Anycast mechanism to achieve load balancing based on directing traffic to the closest data center;
• activating route health injection (RHI) at each active data center using the “advertise active” command;
• monitoring the health of each data center;
• and
• in the event one of said data centers becomes unavailable, causing future traffic to be directed to another data center by modifying an OSPF cost metric of a link to the unavailable data center.

In an autonomous system, a method for load balancing and recovering from a disaster, the method comprising:

• hosting active applications and serving clients from at least two active data centers in said autonomous system;
• advertising the same route from said at least two active data centers;
• routing client traffic to one of said plurality of data centers using IP Anycast mechanism;
• using “advertise active” command in route health injection (RHI) to install a host route in an edge router if a virtual server in said data center is in an operational state;
• advertising the availability of a virtual IP (VIP) address throughout the network;
• injecting, from an internal routing protocol into an external routing protocol, a static route by redistribution;
• configuring route summarization in OSPF;
• and
• configuring BGP route redistribution and route preference to update neighboring routers.