Subject: Re: Fw: masquerading failure for at least icmp and tcp+sack on amd64

From: Marc Lehmann <[email-masked]>
Date: Wed, 7 Sep 2005 23:34:13 +0200

On Wed, Sep 07, 2005 at 02:39:20PM +0200, Patrick McHardy <[email-masked]> wrote:
> Please try if loading the ipt_LOG module and executing
> "echo 255 > /proc/sys/net/ipv4/netfilter/ip_conntrack_log_invalid"
> gives more information

Some more messages I get when logging is enabled:

printk: 1286 messages suppressed.
ip_ct_tcp: invalid state IN= OUT= SRC=84.56.231.206 DST=xxx.xxx.xxx.xxx LEN=52 TOS=0x00 PREC=0x00 TTL=64 ID=3260 DF PROTO=TCP SPT=41535 DPT=119 SEQ=3475818900 ACK=1819416201 WINDOW=12198 RES=0x00 ACK URGP=0 OPT (0101080A00F5DE260917B744) UID=0 
printk: 1166 messages suppressed.
ip_ct_tcp: bad TCP checksum IN= OUT= SRC=xxx.xxx.xxx.xxx DST=84.56.231.206 LEN=1492 TOS=0x00 PREC=0x00 TTL=53 ID=6652 DF PROTO=TCP SPT=119 DPT=41550 SEQ=686563106 ACK=3472571721 WINDOW=55741 RES=0x00 ACK URGP=0 OPT (0101080A091782AB00F5E2EC) 
printk: 1114 messages suppressed.
ip_ct_tcp: bad TCP checksum IN= OUT= SRC=xxx.xxx.xxx.xxx DST=84.56.231.206 LEN=52 TOS=0x00 PREC=0x00 TTL=53 ID=45484 DF PROTO=TCP SPT=119 DPT=41550 SEQ=686606959 ACK=3472571737 WINDOW=55725 RES=0x00 ACK URGP=0 OPT (0101080A0917849E00F5E7B4) 
printk: 1214 messages suppressed.
ip_ct_tcp: bad TCP checksum IN= OUT= SRC=xxx.xxx.xxx.xxx DST=84.56.231.206 LEN=1492 TOS=0x00 PREC=0x00 TTL=53 ID=39527 DF PROTO=TCP SPT=119 DPT=41552 SEQ=2432945453 ACK=3473246510 WINDOW=56283 RES=0x00 ACK URGP=0 OPT (0101080A09182B2000F5ECAC) 
printk: 1320 messages suppressed.
ip_ct_tcp: bad TCP checksum IN= OUT= SRC=xxx.xxx.xxx.xxx DST=84.56.231.206 LEN=1492 TOS=0x00 PREC=0x00 TTL=52 ID=4867 DF PROTO=TCP SPT=119 DPT=41561 SEQ=1077509261 ACK=3487524170 WINDOW=56319 RES=0x00 ACK URGP=0 OPT (0101080A0917ABCD00F5F18F) 
printk: 1190 messages suppressed.
ip_ct_tcp: bad TCP checksum IN= OUT= SRC=xxx.xxx.xxx.xxx DST=84.56.231.206 LEN=1492 TOS=0x00 PREC=0x00 TTL=53 ID=7628 DF PROTO=TCP SPT=119 DPT=41538 SEQ=163747835 ACK=3477529327 WINDOW=56170 RES=0x00 ACK URGP=0 OPT (0101080A098F2AB200F5F682) 
printk: 1172 messages suppressed.

The corresponding connections work just fine, though (and I think I get
more than a single message for every physical packet received).

-- 
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