1. A method for processing packets, comprising: programming a hardware classifier in a network interface card (NIC) to send packets associated with a first packet destination to a non-standby hardware receive ring (HRR), wherein the first packet destination is located on a host; programming a software classifier located on the host to obtain packets from the non-standby HRR; programming the software classifier to send packets for the first packet destination to a first software receive ring (SRR) located on the host, wherein the first packet destination is associated with the first SRR; obtaining identifying information about a denial of service (DoS) attack; in response to obtaining identifying information about the DoS attack: programming the hardware classifier, using the identifying information, to send packets associated with the DoS attack to a standby HRR; receiving a first packet by the hardware classifier; determining, based on the identifying information, that the first packet is associated with the DoS attack; in response to determining, based on the identifying information, that the first packet is associated with the DoS attack, sending the first packet to the standby HRR; receiving a second packet by the hardware classifier; determining, based on the identifying information, that the second packet is not associated with the DoS attack; in response to determining, based on the identifying information, that the second packet is not associated with the DoS attack, sending the second packet to the non-standby HRR; and obtaining, by the software classifier, the second packet from the non-standby ring, wherein the standby HHR and the non-standby HRR are located on the NIC, wherein packets sent to the standby HRR are not sent to the host, wherein the NIC is interposed between the host and a network, and wherein the NIC is configured to receive, from the network, packets addressed to the host.