Bi-directional affinity within a load-balancing multi-node network interface

A network load-balancing/external network interface node, for use in a system including multiple network load-balancing/external network interface nodes, including bi-directional load-balancing affinity with regard to requests from external clients and corresponding responses from internal network servers, the network load-balancing/external network interface comprising:

• an external network load-balancing adapter that executes a load-balancing algorithm to determine whether a received client request is accepted by the network load-balancing/external network interface node;
• an external network interface utility that processes the received client request and maintains state information associated with the received client request;
• an internal network load-balancing adapter that ensures the network load-balancing/external network interface node accepts a response from an internal network server corresponding to the received client request, the internal network load-balancing adapter comprising:
• a complementary load-balancing algorithm to determine whether the received server response is accepted by the network load-balancing/external network interface node, the complementary load-balancing algorithm rendering a same network load-balancing/external network interface node selection as the received client request, and
• an indicator set statically indicating that complementary load-balancing algorithm is selectively invoked.

A method for establishing bi-directional affinity for a load balancing firewall comprising multiple load balancing/firewall nodes interposed between an internal network comprising multiple published servers that are identified within a list maintained by the load balancing/firewall node, and an external network comprising requesting clients, the method comprising:

• first receiving, by an external network load balancing interface of the load balancing firewall, a request from an external client;
• first determining, based upon a load-balancing algorithm, a selected load balancing/firewall node that processes the request from the external client;
• establishing, by the selected load balancing/firewall node, a connection state corresponding to the request from the external client;
• passing, by the selected load balancing/firewall node, the request from the external client to a selected one of the multiple published servers;
• second receiving, by an internal network load balancing interface of the load balancing firewall, a message from the selected one of the multiple published servers;
• second determining, in response to the second receiving step, whether the address of the selected one of the multiple published servers is present in the list of published servers;
• and
• applying, by the internal network load balancing interface of the load balancing firewall, a complementary load-balancing algorithm to the message received during the second receiving step, in response to identifying the selected one of the multiple published servers within the list of published server during the second determining step, the complementary load-balancing algorithm determining the selected load balancing/firewall node established during the first determining step;
• and
• processing, by the selected load balancing/firewall node, the message from the selected one of the multiple published servers.

A computer-readable medium having computer-executable components thereon for a load balancing firewall comprising multiple load balancing/firewall nodes interposed between an internal network comprising multiple published servers that are identified within a list maintained by the load balancing/firewall node, and an external network comprising requesting clients, the components performing the steps of:

• first receiving, by an external network load balancing interface of the load balancing firewall, a request from an external client;
• first determining, based upon a load-balancing algorithm, a selected load balancing/firewall node that processes the request from the external client;
• establishing, by the selected load balancing/firewall node, a connection state corresponding to the request from the external client;
• passing, by the selected load balancing/firewall node, the request from the external client to a selected one of the multiple published servers;
• second receiving, by an internal network load balancing interface of the load balancing firewall, a message from the selected one of the multiple published servers;
• second determining, in response to the second receiving step, whether the address of the selected one of the multiple published servers is present in the list of published servers;
• and
• applying, by the internal network load balancing interface of the load balancing firewall, a complementary load-balancing algorithm to the message received during the second receiving step, in response to identifying the selected one of the multiple published servers within the list of published server during the second determining step, the complementary load-balancing algorithm determining the selected load balancing/firewall node established during the first determining step;
• and
• processing, by the selected load balancing/firewall node, the message from the selected one of the multiple published servers.

A method for establishing bi-directional affinity for a load balancing firewall comprising multiple load balancing/firewall nodes interposed between an internal network comprising multiple published servers and an external network comprising requesting clients, the method comprising:

• first receiving, by an external network load balancing interface of the load balancing firewall, a request from an external client;
• first determining, based upon a load-balancing algorithm, a selected load balancing/firewall node that processes the request from the external client;
• evaluating, by the selected load balancing/firewall node, the request from the external client to determine whether to establish bi-directional affinity;
• establishing, by the selected load balancing/firewall node, a connection state corresponding to the request from the external client;
• passing, by the selected load balancing/firewall node, the request from the external client to a selected one of the multiple published servers;
• second receiving, by an internal network load balancing interface of the load balancing firewall, a message from the selected one of the multiple published servers;
• and
• applying, by the internal network load balancing interface of the load balancing firewall, a complementary load-balancing algorithm to the message received during the second receiving step, in response to determining establishment of bi-directional affinity during the evaluating step, the complementary load-balancing algorithm determining the selected load balancing/firewall node established during the first determining step;
• and
• processing, by the selected load balancing/firewall node, the message from the selected one of the multiple published servers.