Brocade Virtual ADX Installation and Deployment Guide (Supporting ADX v03.1.00) - Manual (Page 24)

FIGURE 2 Hardware checksum offload process
NOTE
Check the network adapter manual to know if it supports the hardware checksum offload functionality.
Incoming packets
Use the VMXNET3 driver which supports incoming packet checksum offload.
Brocade Virtual ADX relies on the network adapter to verify the TCP, UDP and IP checksums for
incoming packets. If the network adapter does not support checksum verification, the Brocade Virtual
ADX software does the checksum verification.
NOTE
If the network adapter returns a TCP, UDP or IP checksum error, the Brocade Virtual ADX software
will also verify the incoming packet, because it is possible that an undetermined fault on the network
adapter caused it to return the checksum error.
Outgoing packets
Use the VMXNET3 driver, which supports outgoing packet checksum offload.
By default, TCP checksum offload is disabled and checksum calculation is performed by the Brocade
Virtual ADX software.
Enabling or disabling TCP checksum offload
Ensure that your network adaptor supports checksum offload prior to enabling TCP checksum offload.
Incoming packets
24 Brocade Virtual ADX Installation and Deployment Guide
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