I've been busy trying to track down these ping issues and it appears
to be a problem with the actual ping program supplied with open rather
than a network problem.

I know get the following results from the mesh router

r...@generic:~# /usr/bin/ping -M do -s 1472 google.com
PING google.com (74.125.39.105) 1472(1500) bytes of data.
72 bytes from fx-in-f105.1e100.net (74.125.39.105): icmp_seq=1 ttl=53
(truncated)
72 bytes from fx-in-f105.1e100.net (74.125.39.105): icmp_seq=2 ttl=53
(truncated)

r...@generic:~# /usr/bin/ping -M do -s 1473 google.com
PING google.com (74.125.39.99) 1473(1501) bytes of data.
>From 192.168.1.123 icmp_seq=1 Frag needed and DF set (mtu = 1500)
>From 192.168.1.123 icmp_seq=1 Frag needed and DF set (mtu = 1500)

So large pings appear to be going over the batman interface.

However still not getting any web traffic through

r...@generic:~# echo "HEAD / HTTP/1.1\nHost: git.open-mesh.net\n\n"|nc
git.open-mesh.net 80


r...@generic:~# wget http://www.google.com
Connecting to www.google.com (74.125.39.104:80)

What else can i provide to help track down the problem here :-(

Dave

On Tue, Aug 17, 2010 at 11:14 AM, David Beaumont <[email protected]> wrote:
>
> The plot thickens..
>
> i started producing the tcp dumps that you requested to take a look at
> and noticed the following.
>
> On the main internet node, if i ping google.com everything is fine.
> However if i ping -s 1464 google.com i do not get a reply, this isn't
> even going over the batman interface. So it looks like i have more of
> a local problem.
>
> To clarify
>
> ping -s 1464 google.com
>
> results in ping requests being sent and recieved on ETH1, but not
> being returned to br-lan
>
> ping google.com
>
> results in ping requests being sent and recieved on ETH1, and being
> returned on br-lan
>
> ping -s 84 google.com will work
> ping -s 85 google.com will not work.
>
> I've never encountered these issues before, but i think they are the
> route cause of my problem? As was initially stated an MTU issue, i
> just need to find where!
>
> echo "HEAD / HTTP/1.1\nHost: git.open-mesh.net\n\n"|nc git.open-mesh.net 80
>
> from the mesh node brings no results, although works as expected on
> the internet node.
>
>
>
>
>
>
>
>
>
> On Mon, Aug 16, 2010 at 7:32 PM, Sven Eckelmann <[email protected]> wrote:
> > David Beaumont wrote:
> >> Sorry for the late reply, a few things came up over the weekend that i
> >> had to attend to.
> >>
> >> Here are three tcp dump files from the internet node on bat0 and one
> >> on eth1 (the internet port)
> >>
> >> Really don't understand what is wrong here :-(
> >
> > Ok, test plan:
> >
> >  * Find the machine and interface were a response from google.com could be
> >   received but which will not forward it to the other interface
> >  * take a real dump on all interfaces (wan and lan)
> >   tcpdump -s 0 -i eth1 -w eth1.dump
> >  * when the response packet is forwarded over the lan/bat0 interface but
> >   doesn't get to the final machine than please also create a tcpdump on the
> >   receiving machine (real interface and maybe bat0)
> >  * Go to your router and check mtu of your wan interface
> >  * Try to ping google.com with the maximum size (mtu - 28 bytes, for example
> >   mtu 1492): ping -M do -s 1464 google.com
> >  * Send small tcp packet with small tcp response:
> >   echo "HEAD / HTTP/1.1\nHost: git.open-mesh.net\n\n"|nc git.open-mesh.net 
> > 80
> >
> > Best regards,
> >        Sven
> >

Reply via email to