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Many tcp "Bad Checksum" on linux server. Does that mean LAN card is broken ?

Posted on 2010-09-16
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Last Modified: 2012-05-10
Hi,
 I've made tcpdump on a linux server - fedora 8.
when I open the cap file with wireshark I see a lot of Errors - at the TCP section :
Checksum: 0xa771 [incorrect, should be 0xa5f8 (maybe caused by "TCP checksum offload"?)]

I guess that's not normal. Does it mean that I have to change my LAN card ?
there are no kernel errors in /var/log/messages log

thank you.
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Question by:severel
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gremwell earned 500 total points
ID: 33692792
These errors can appear if your system offloads TCP checksum calculation to NIC. You can disable this feature, but it may increase CPU utilization on your system as CPU will have to deal with checksum calculation. http://www.meshwalk.com/?p=34
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