Maintained by: NLnet Labs

[Unbound-users]   bad udp/tcp cksum logged in all queries

Fri Sep 12 11:31:59 CEST 2014

under linux/unix platform, youcan turn off the checksum for packet:
the command is /sbin/ethtool -K eth0 rx off tx off.

------------------ Original ------------------
From:  "shmick at";<shmick at>;
Date:  Fri, Sep 12, 2014 05:12 PM
To:  "unbound-users"<unbound-users at>; 

Subject:  [Unbound-users] bad udp/tcp cksum logged in all queries


could i please have some feedback about what possible reasons would
cause this ?

for example: > Flags [S], cksum 0x0f97
(incorrect -> 0xa32b), seq 2709415216, win 29200, options [mss
1460,sackOK,TS val 60120911 ecr 0,nop,wscale 7], length 0 > [bad udp cksum 0xec18 -> 0xaa99!]
12116% [1au] DS? 31.192.iN-aDdr.aRpA. ar: . OPT UDPsize=4096 OK (48)
18:21:34.244863 IP (tos 0x0, ttl 52, id 11573, offset 0, flags [none],
proto UDP (17), length 531)

i never noticed this but i don't have any issues at all receiving
replies with udp/tcp checksums ok

the question remains, although these are logged, is it a problem ?

unbound 1.4.22 from debian jessie amd-64 repos

any other relevant settings required & i can revert
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