On 2016-01-23, Pedro Caetano <[email protected]> wrote: > The checksum errors are visible in tcpdump. > > pcaetano@soekris $ > doas tcpdump -nnvvr badchecksum.cap > 23:18:56.258991 89.115.7.49.38924 > 129.128.5.194.80: S [bad tcp cksum > e818! -> d08e] 2129156372:2129156372(0) win 16384 <mss > 1460,nop,nop,sackOK,nop,wscale 3,nop,nop,timestamp 293911467 0> (DF) (ttl > 64, id 62808, len 64)
These aren't real errors. You'll note that they concern outgoing packets. em(4) supports hardware checksum offloading. The checksum is filled in only _after_ tcpdump has seen the packet. (I can't comment on your overall problem.) -- Christian "naddy" Weisgerber [email protected]
