-----Original Message-----
From: Darren Reed
To: Martti Kuparinen
Cc: Nick Evans; [email protected]; [EMAIL PROTECTED]
Sent: 12/4/2005 5:17 AM
Subject: Re: 4.1.x, OOW and a packet capture.
Having looked at some packet dumps from Nick, the "OOW" problem seems
to be caused by TCP SACK.
e.g.
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330003176:330004636(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330003176:330004636(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330004636:330006096(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330006096:330007556(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520 (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330009016:330010476(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330010476:330011936(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330011936:330013396(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330013396:330014856(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330013396:330014856(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330009016} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330010476} > (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330014856:330016316(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330011936} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330013396} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330013396} > (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330017776:330019236(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330019236:330020696(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330014856} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330016316} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330017776} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330019236} > (DF)
1.1.1.1.2601 > 1.1.1.2.netbios-ssn: . ack 330004636 win 17520
<nop,nop,sack sack 1 {330006096:330020696} > (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330020696:330022156(1460) ack
3945818187 win 62880 NBT Packet (DF)
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330004636:330006096(1460) ack
3945818187 win 62880 NBT Packet (DF)
OOW:
1.1.1.2.netbios-ssn > 1.1.1.1.2601: . 330004636:330006096(1460) ack
3945818187 win 62880 NBT Packet (DF)
Darren
Hmm. The far side of this transfer doesn't have SACK support. That shouldn't
upset matters any, should it? There's a bigger problem in that it seems that
commenting out the OOW check in 4.1.9 fixes the issue however on an older
system with 4.1.2 we still see the problem even with the OOW check disabled.
We'll disable SACK on the Windows box and see what happens to the transfer.
