Martin, this workaround is documented at
http://www.shorewall.net/XenMyWay-Routed.html
which is an interesting Xen setup.

you can put the line "ethtool -K <device> tx off" in your interfaces
file (e.g. directly beneath each interface configuration stanza) to
ensure this persists across reboots.

Werner


On Mon, 2008-03-31 at 13:19 +0200, Martin Leben wrote:
> Alexander Wilms wrote:
> > Hi Martin,
> > 
> > this reminds me of a FTP conntrack problem I had with Xen a while ago.
> > It's related to the common Xen checksum offload problem.
> > First FTP port packet has incorrect checksum and is dropped. Then the 
> > resent 
> > packet is ignored by the ftp_conntrack module and doesn't get masq'ed. E 
> > voila, you have your internal address in the port command.
> > 
> > Diagnosis: run tcpdump -vv (or even better wireshark) on the involved 
> > interfaces and you'll see a lot of invalid checksums
> > 
> > Solution: disable tx-checksumming on ALL interfaces (ethtool -K <device> tx 
> > off).
> 
> Hi Alexander,
> 
> Voila! That did it. Now it works. I ran
> # ethtool -K <device> tx off
> ... on the firewalls both network interfaces as well as on the FTP server 
> network interface.
> 
> Big thanks to you, Andrew and Tom for your time and input.
> 
> Tom, I think this is something for the documentation.
> 
> /Martin Leben
> 
> 
> -------------------------------------------------------------------------
> Check out the new SourceForge.net Marketplace.
> It's the best place to buy or sell services for
> just about anything Open Source.
> http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
> _______________________________________________
> Shorewall-users mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/shorewall-users


-------------------------------------------------------------------------
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
_______________________________________________
Shorewall-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/shorewall-users

Reply via email to