The following reply was made to PR kern/29544; it has been noted by GNATS.

From: Martin Husemann <martin@duskware.de>
To: john heasley <heas@shrubbery.net>
Cc: thorpej@netbsd.org, gnats-bugs@NetBSD.org
Subject: Re: kern/29544
Date: Sat, 5 Mar 2005 19:24:30 +0100

 On Sat, Mar 05, 2005 at 03:40:10PM +0000, john heasley wrote:
 > Could you provide any other environment specifics?  ipf/pf, ipsec, or a
 > router involved?
 
 There is realy nothing special that I can see. I have INET6 in the NFS servers
 kernel, but don't use it (yet). No IPF/PF, no ipsec, no router. MTU is 1500
 on all interfaces, both on client and server.
 
 The NFS server has another interface (fxp0), but that is unused. The only
 special option in the kernel is MULTIPROCESSOR.
 
 The wm0 is connected to an unmanaged 100Mbit switch, which also connects
 to one of the clients, a sparc64 machine with hme (not using any checksum
 offloads). The other client I tried is an i386 notebook behind a wavelan
 AP. Both react the same, so I guess it's the server.
 
 I'll attach some pkt traces - maybe this helps. The log from the server say
 "bad cksum 0" (as expected, right?) but the client says "bad cksum ffff", and
 that probably is not ok.
 
 Martin
 
 server: night-porter, client: sunny-weather
 tcpdump on client:
 
 tcpdump: listening on hme0, link-type EN10MB (Ethernet), capture size 2000 bytes
 19:18:54.350781 IP (tos 0x0, ttl  64, id 1732, offset 0, flags [none], length: 84) sunny-weather.duskware.de.1008 > night-porter.duskware.de.sunrpc: [udp sum ok] UDP, length: 56
 19:18:54.351995 IP (tos 0x0, ttl  64, id 1877, offset 0, flags [none], length: 56) night-porter.duskware.de.sunrpc > sunny-weather.duskware.de.1008: [udp sum ok] UDP, length: 28
 19:18:54.352259 IP (tos 0x0, ttl  64, id 1733, offset 0, flags [none], length: 84) sunny-weather.duskware.de.1007 > night-porter.duskware.de.sunrpc: [udp sum ok] UDP, length: 56
 19:18:54.353777 IP (tos 0x0, ttl  64, id 1878, offset 0, flags [none], length: 56) night-porter.duskware.de.sunrpc > sunny-weather.duskware.de.1007: [udp sum ok] UDP, length: 28
 19:18:54.354141 IP (tos 0x0, ttl  64, id 1734, offset 0, flags [none], length: 160) sunny-weather.duskware.de.1006 > night-porter.duskware.de.1020: [udp sum ok] UDP, length: 132
 19:18:54.358095 IP (tos 0x0, ttl  64, id 1880, offset 0, flags [none], length: 96) night-porter.duskware.de.1020 > sunny-weather.duskware.de.1006: [udp sum ok] UDP, length: 68
 19:18:54.358354 IP (tos 0x0, ttl  64, id 1735, offset 0, flags [none], length: 148) sunny-weather.duskware.de.2675204107 > night-porter.duskware.de.nfs: 120 getattr fh 18,0/1931
 19:18:54.358754 IP (tos 0x0, ttl  64, id 1881, offset 0, flags [none], length: 140) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204107: reply ok 112 getattr DIR 775 ids 205/100 sz 0x600
 19:18:54.358826 IP (tos 0x0, ttl  64, id 1736, offset 0, flags [none], length: 120) sunny-weather.duskware.de.2675204108 > night-porter.duskware.de.nfs: 92 fsinfo fh 18,0/1931
 19:18:54.359933 IP (tos 0x0, ttl  64, id 1882, offset 0, flags [none], length: 192) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204108: reply ok 164 fsinfo POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046580.508220000 1109677039.602317000 1109677059.270389000 rtmax 32768 rtpref 32768 wtmax 32768 wtpref 32768 dtpref 32768 rtmult 512 wtmult 512 maxfsz 0x1ffffffffff delta 0.000001 
 19:18:54.360014 IP (tos 0x0, ttl  64, id 1737, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:18:54.361108 IP (tos 0x0, ttl  64, id 1883, offset 0, flags [+], length: 1500, bad cksum ffff (->a023)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046734.649405000 1109677039.602317000 1109677059.270389000 verf 4229f7117ff89ec0
 19:18:54.361140 IP (tos 0x0, ttl  64, id 1883, offset 1480, flags [none], length: 424) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:18:57.374999 IP (tos 0x0, ttl  64, id 1742, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:18:57.375773 IP (tos 0x0, ttl  64, id 1889, offset 0, flags [+], length: 1500, bad cksum ffff (->a01d)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046737.659038000 1109677039.602317000 1109677059.270389000 verf 4229f7117ff89ec0
 19:18:57.375802 IP (tos 0x0, ttl  64, id 1889, offset 1480, flags [none], length: 424) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:19:03.405323 IP (tos 0x0, ttl  64, id 1743, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:19:03.405983 IP (tos 0x0, ttl  64, id 1896, offset 0, flags [+], length: 1500, bad cksum ffff (->a016)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046743.409992000 1109677039.602317000 1109677059.270389000 verf 4229f7117ff89ec0
 19:19:03.406017 IP (tos 0x0, ttl  64, id 1896, offset 1480, flags [none], length: 424) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:19:15.455977 IP (tos 0x0, ttl  64, id 1744, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:19:15.456711 IP (tos 0x0, ttl  64, id 1909, offset 0, flags [+], length: 1500, bad cksum ffff (->a009)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046755.458521000 1109677039.602317000 1109677059.270389000 verf 4229f7117ff89ec0
 19:19:15.456742 IP (tos 0x0, ttl  64, id 1909, offset 1480, flags [none], length: 424) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:19:39.547271 IP (tos 0x0, ttl  64, id 1786, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 
 23 packets captured
 545 packets received by filter
 0 packets dropped by kernel
 
 And on server:
 
 tcpdump: listening on wm0, link-type EN10MB (Ethernet), capture size 2000 bytes
 19:18:54.630176 IP (tos 0x0, ttl  64, id 1732, offset 0, flags [none], length: 84) sunny-weather.duskware.de.1008 > night-porter.duskware.de.sunrpc: [udp sum ok] UDP, length: 56
 19:18:54.631194 IP (tos 0x0, ttl  64, id 1877, offset 0, flags [none], length: 56, bad cksum 0 (->c5cd)!) night-porter.duskware.de.sunrpc > sunny-weather.duskware.de.1008: [bad udp cksum 7df3!] UDP, length: 28
 19:18:54.631606 IP (tos 0x0, ttl  64, id 1733, offset 0, flags [none], length: 84) sunny-weather.duskware.de.1007 > night-porter.duskware.de.sunrpc: [udp sum ok] UDP, length: 56
 19:18:54.632977 IP (tos 0x0, ttl  64, id 1878, offset 0, flags [none], length: 56, bad cksum 0 (->c5cc)!) night-porter.duskware.de.sunrpc > sunny-weather.duskware.de.1007: [bad udp cksum cdf!] UDP, length: 28
 19:18:54.633462 IP (tos 0x0, ttl  64, id 1734, offset 0, flags [none], length: 160) sunny-weather.duskware.de.1006 > night-porter.duskware.de.1020: [udp sum ok] UDP, length: 132
 19:18:54.637284 IP (tos 0x0, ttl  64, id 1880, offset 0, flags [none], length: 96, bad cksum 0 (->c5a2)!) night-porter.duskware.de.1020 > sunny-weather.duskware.de.1006: [bad udp cksum dac2!] UDP, length: 68
 19:18:54.637747 IP (tos 0x0, ttl  64, id 1735, offset 0, flags [none], length: 148) sunny-weather.duskware.de.2675204107 > night-porter.duskware.de.nfs: 120 getattr fh 18,0/1931
 19:18:54.637933 IP (tos 0x0, ttl  64, id 1881, offset 0, flags [none], length: 140, bad cksum 0 (->c575)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204107: reply ok 112 getattr DIR 775 ids 205/100 sz 0x600
 19:18:54.638206 IP (tos 0x0, ttl  64, id 1736, offset 0, flags [none], length: 120) sunny-weather.duskware.de.2675204108 > night-porter.duskware.de.nfs: 92 fsinfo fh 18,0/1931
 19:18:54.639103 IP (tos 0x0, ttl  64, id 1882, offset 0, flags [none], length: 192, bad cksum 0 (->c540)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204108: reply ok 164 fsinfo POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046580.508220000 1109677039.602317000 1109677059.270389000 rtmax 32768 rtpref 32768 wtmax 32768 wtpref 32768 dtpref 32768 rtmult 512 wtmult 512 maxfsz 0x1ffffffffff delta 0.000001 
 19:18:54.639319 IP (tos 0x0, ttl  64, id 1737, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:18:54.640036 IP (tos 0x0, ttl  64, id 1883, offset 0, flags [+], length: 1500, bad cksum 0 (->a023)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046734.649405000 1109677039.602317000 1109677059.270389000 verf 11f72942c09ef87f
 19:18:54.640051 IP (tos 0x0, ttl  64, id 1883, offset 1480, flags [none], length: 424, bad cksum 0 (->c39e)!) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:18:57.654405 IP (tos 0x0, ttl  64, id 1742, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:18:57.654664 IP (tos 0x0, ttl  64, id 1889, offset 0, flags [+], length: 1500, bad cksum 0 (->a01d)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046737.659038000 1109677039.602317000 1109677059.270389000 verf 11f72942c09ef87f
 19:18:57.654679 IP (tos 0x0, ttl  64, id 1889, offset 1480, flags [none], length: 424, bad cksum 0 (->c398)!) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:19:03.206906 IP (tos 0x0, ttl  64, id 1743, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:19:03.207093 IP (tos 0x0, ttl  64, id 1896, offset 0, flags [+], length: 1500, bad cksum 0 (->a016)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046743.409992000 1109677039.602317000 1109677059.270389000 verf 11f72942c09ef87f
 19:19:03.207103 IP (tos 0x0, ttl  64, id 1896, offset 1480, flags [none], length: 424, bad cksum 0 (->c391)!) night-porter.duskware.de > sunny-weather.duskware.de: udp
 19:19:15.456837 IP (tos 0x0, ttl  64, id 1744, offset 0, flags [none], length: 168) sunny-weather.duskware.de.2675204109 > night-porter.duskware.de.nfs: 140 readdir fh 18,0/1931 8192 bytes @ 0x0 verf 0000000000000000
 19:19:15.457099 IP (tos 0x0, ttl  64, id 1909, offset 0, flags [+], length: 1500, bad cksum 0 (->a009)!) night-porter.duskware.de.nfs > sunny-weather.duskware.de.2675204109: reply ok 1472 readdir POST: DIR 775 ids 205/100 sz 0x600 nlink 51 rdev 3681/39880 fsid 0x1200 fileid 0x25a1d4b a/m/ctime 1110046755.458521000 1109677039.602317000 1109677059.270389000 verf 11f72942c09ef87f
 19:19:15.457113 IP (tos 0x0, ttl  64, id 1909, offset 1480, flags [none], length: 424, bad cksum 0 (->c384)!) night-porter.duskware.de > sunny-weather.duskware.de: udp
 
 22 packets captured
 363 packets received by filter
 0 packets dropped by kernel