From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jim Pick Subject: Re: Masquerading problems - XenU 3.0 on x86_64 Date: Sun, 09 Apr 2006 13:18:34 -0700 Message-ID: <44396C1A.5020102@jimpick.com> References: <44384EDA.2080106@jimpick.com> <6677c9ee1b32caad4ff87bf462512ee3@cl.cam.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: xen-devel Devel , netfilter-devel@lists.netfilter.org Return-path: To: Keir Fraser In-Reply-To: <6677c9ee1b32caad4ff87bf462512ee3@cl.cam.ac.uk> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com List-Id: netfilter-devel.vger.kernel.org Keir Fraser wrote: > > On 9 Apr 2006, at 01:01, Jim Pick wrote: > >> I'm trying to migrate my Xen sessions installed on 32-bit Xen 2.0 >> server to a 64-bit Xen 3.0 server. >> >> On the Xen 2.0 server (32-bit), I built a DomU kernel with >> masquerading, and I use that to do NAT for some private networks >> running on the same box. >> >> When I tried to do it with Xen 3.0 (64-bit), I couldn't get it to >> work. I had to build a custom DomU kernel (from xen-3.0-testing.hg, >> 2.6.16, 2 days ago) in order to include the netfilter/iptables code. >> ICMP works. TCP doesn't. Non-masquerading traffic is OK. I had the >> same problems with the 2.6.12 kernel from Xen 3.0.1. >> >> I captured some of the traffic, and ethereal is showing that the >> masqueraded traffic being output has bad TCP checksums. >> >> I'm going to have to do some debugging to try to figure out what's >> going wrong. >> >> Has anybody else encountered this? Also, if it's already been fixed >> somewhere, I'd love to know. Any Netfilter debugging tips would also >> be appreciated. > > > Turn off tx checksum offload in your domU's using ethtool. We had fixed > some forms of NAT with our checksum offload, but maybe not for your type > of setup. That fixed it. Thanks! Cheers, - Jim