http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=447

Summary: dom0 netfilter DNAT rule that rewrites the destination port doesn't work with domU TX checksum offload Product: Xen Version: 3.0-testing Platform: x86-64 OS/Version: Linux-2.6 Status: NEW Severity: normal Priority: P2 Component: Unspecified AssignedTo: xen-...@lists.xensource.com ReportedBy: mgoo...@csua.berkeley.edu

A rule like this in dom0:

iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j DNAT --to-destination $DOMU_IP:7800

doesn't work unless in the domU, I run:

ethtool -K eth0 tx off

If the DNAT rule preserves the destination port, it works.