Date: Wed, 8 Jul 2015 11:05:39 +0300 From: Pavel Timofeev <timp87@gmail.com> To: Slawa Olhovchenkov <slw@zxy.spb.ru> Cc: freebsd-current@freebsd.org, "freebsd-virtualization@freebsd.org" <freebsd-virtualization@freebsd.org> Subject: Re: MS DNS doesn't answer to CURRENT under Hyper-V Message-ID: <CAAoTqft_u1YEOGf6pThhHd-JuYoGnxzQxFpo-57SCUJ0OksWGw@mail.gmail.com> In-Reply-To: <20150707154906.GA44094@zxy.spb.ru> References: <CAAoTqftvtQunx%2BWCL4%2BBz-mYSgqCTcGx1aAyemfaz%2B=0ogZuWw@mail.gmail.com> <20150707130902.GA41189@zxy.spb.ru> <CAAoTqfsUfdAP1G=U4eDg3hfmuHtoosgGjOd9gMrehX%2BrcxaiJw@mail.gmail.com> <20150707154906.GA44094@zxy.spb.ru>
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Ok, r284746 is the root of the problem. MS DNS works under r284745 and doesn't work under r284746. Slawa, what should I look at in wireshark output? 2015-07-07 18:49 GMT+03:00 Slawa Olhovchenkov <slw@zxy.spb.ru>: > On Tue, Jul 07, 2015 at 06:04:46PM +0300, Pavel Timofeev wrote: > >> Well, turning off checksum offloading by `ifconfig hn0 -txcsum >> -rxcsum` definitely helps. >> >> As for tcpdump I'm not completely sure if I did it right, but I see >> "bad udp cksum" phrase: >> >> # tcpdump -i hn0 -vvv -nn udp dst port 53 >> tcpdump: listening on hn0, link-type EN10MB (Ethernet), capture size >> 262144 bytes >> 18:01:19.139994 IP (tos 0x0, ttl 64, id 61218, offset 0, flags [none], >> proto UDP (17), length 51) >> 192.168.25.26.45683 > 192.168.25.3.53: [bad udp cksum 0xb39e -> >> 0xf210!] 52886+ A? ya.ru. (23) >> 18:01:24.140544 IP (tos 0x0, ttl 64, id 17293, offset 0, flags [none], >> proto UDP (17), length 51) >> 192.168.25.26.12575 > 192.168.25.3.53: [bad udp cksum 0xb39e -> >> 0x7365!] 52886+ A? ya.ru. (23) > > tcpdump "bad udp cksum" is normal on FreeBSD host in case checksum > offload (and may be need only for help finding issuse in code). Need > wireshark capturing from MS DNS host (or from mirroring port).
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