Date: Thu, 23 May 2002 11:18:03 +0300 From: Fred Souza <cseg@storming.org> To: stable@freebsd.org Cc: hackers@freebsd.org Subject: Bad TCP checksum Message-ID: <20020523081803.GA1730@torment.storming.org>
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Hi everyone, I'm experiencing something weird with my 4.6-RC box (compile of May 18). What happens is that for some hosts it just won't calculate the checksum properly, and thus my box is unable to start TCP connections to those hosts. Here's a piece of the output of tcpdump: 19:16:55.759657 me.50441 > somehost.http: S [bad tcp cksum fffe!] 2079216431:2079216431(0) win 65535 <mss 1452,nop,wscale 1,nop,nop, timestamp 797082 0> (DF) [tos 0x10] (ttl 96, id 41580, len 60) Additional info that might help: The default route goes through the tun0 interface, my ADSL service uses PPPoE and therefore I cannot think of any other way to work it out on FreeBSD. ppp(8) was compiled in the same day as the kernel, and I tried unloading firewalling and nothing different occured (at least apparently). NAT is disabled here. Since I saw once something similar happening, I think it's good to mention that these lines exist in my /etc/make.conf: CFLAGS= -O2 COPTFLAGS+= -O2 CPUTYPE=k6-2 They're in accordance with my K6-2 box. Just mentioned that because once I saw a box unable to connect to some hosts because it was a Pentium II with the kernel compiled for K6-2 boxes. What should I do? Please, CC any replies to me too, because I'm not subscribed to the lists. If any other output/detail is necessary, please ask away. Thank you very much in advance, Fred -- "I'd love to go out with you, but I never go out on days that end in `Y.'" To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message
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