Check-point based high availability: network packet buffering in hardware

A method, system, and computer program product enhances resource/process availability by providing hardware based buffering of network packets during checkpointing in a virtualized environment. A High Availability Checkpoint (HAC) utility pre-configures a physical network adapter to buffer outgoing network packets from virtual machines that employ a checkpointing technology. In response to receiving an outgoing network packet from a virtual machine and determining that the virtual machine employs a pre-specified checkpointing technology, the physical network adapter buffers the outgoing network packet. In addition, a primary host performs/facilitates checkpoint operations (associated with the virtual machine) with a secondary host. When checkpoint operations are successfully completed, the HAC utility triggers the transmission of the buffered network packets from the network adapter to a network destination. The physical network adapter minimizes checkpointing network latency by pre-assigning a higher priority to a buffered network packet from a checkpointing virtual machine than to a new network packet that originates from a non-checkpointing virtual machine.