Network appliance having forwarding traffic mode to reduce traffic loss and related methods

A method for establishing sessions between client devices and at least one network server for exchanging network traffic therebetween using a network appliance, the method comprising:

• establishing new sessions for network traffic based upon new session requests from the client devices;
• forwarding network traffic associated with prior existing sessions from the client devices to the at least one network server;
• upon startup of the network appliance during a continuous flow of new session requests, entering a forwarding traffic mode and forwarding unknown network traffic not associated with a prior existing session or a new session request to the at least one network server so that the unknown network traffic is not blocked from reaching the at least one network server during the startup;
• and
• in a normal traffic mode, blocking the unknown network traffic not associated with a prior existing session or a new session request from reaching the at least one network server.

A non-transitory computer-readable medium for a network appliance, the network appliance for establishing sessions between client devices and at least one network server for exchanging network traffic therebetween, the non-transitory computer-readable medium having computer-executable instructions for causing the network appliance to perform steps comprising:

• establishing new sessions for network traffic based upon new session requests from the client devices;
• forwarding network traffic associated with prior existing sessions from the client devices to the at least one network server;
• upon startup of the network appliance during a continuous flow of new session requests, entering a forwarding traffic mode and forwarding unknown network traffic not associated with an existing session or a new session request to the at least one network server so that the unknown network traffic is not blocked from reaching the at least one network server during the startup;
• and
• in a normal traffic mode, blocking the unknown network traffic not associated with an existing session or a new session request from reaching the at least one network server.