All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Niccolò Belli" <darkbasic@linuxsystems.it>
To: netfilter@vger.kernel.org
Cc: wireshark-users@wireshark.org, lartc@lists.linuxsystems.it
Subject: Re: Problem with ip spoofing load balancing
Date: Wed, 26 Oct 2011 22:38:55 +0200	[thread overview]
Message-ID: <4EA86FDF.8090906@linuxsystems.it> (raw)
In-Reply-To: <alpine.LFD.2.00.1110262235340.1558@ja.ssi.bg>

Il 26/10/2011 21:43, Julian Anastasov ha scritto:
> 	I looked at broken-spoofing-server.pcap and
> broken-spoofing-client.pcap
>
> 	It looks like that this packet comes after some
> packet that is dropped before server:
>
> IP 2.119.245.36.80>  88.38.77.130.39243: Flags [P.], seq 1449:1534, ack 602, win 438, options [nop,nop,TS val 17124611 ecr 56937089], length 85
>
> 	May be the seq 1:1449 packet can not reach 2.119.245.36.80,
> that is why it does not go to client 88.38.77.130.39243.
> May be server is a virtual server or something like that.
>
> 	I guess someone before 2.119.245.36.80 is sending
> large packets and some MTU is low and may be due to missing
> ICMP the sender there can not learn the lower path MTU.
> May be client can use ip route add ... advmss 1400 to check
> if problem is fixed that way. May be there is some tunnel
> behind the server that uses lower MTU.
>
> 	Note that some 3.0.X kernels have problem that
> ICMP is not sent and this can cause PMTU problems.

SOLVED! Thanks Julian Anastasov.

Niccolò

       reply	other threads:[~2011-10-26 20:38 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <4EA821DD.1050306@linuxsystems.it>
     [not found] ` <alpine.LFD.2.00.1110262235340.1558@ja.ssi.bg>
2011-10-26 20:38   ` Niccolò Belli [this message]
2011-10-25 22:10 Problem with ip spoofing load balancing Niccolò Belli

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4EA86FDF.8090906@linuxsystems.it \
    --to=darkbasic@linuxsystems.it \
    --cc=lartc@lists.linuxsystems.it \
    --cc=netfilter@vger.kernel.org \
    --cc=wireshark-users@wireshark.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.