The nat tcp-checksum adjust enable command enables a device to automatically change the checksum of a TCP packet after the device performs NAT for the packet.
The undo nat tcp-checksum adjust enable command disables the function.
The IP addresses of TCP packets need to be translated when the packets traverse the NAT device, so the checksum of the TCP packets needs to be recounted. Some devices, such as Netgear, cannot forward the packets whose checksum is 0xFFFF. To make the packets whose checksum is 0xFFFF forwarded normally, FW can change these checksums from 0xFFFF to 0x0 when being connected to such devices.
By default, this function is disabled.