|   xen-devel
Re: [Xen-devel] xen.git branch reorg 
| | Chris, 
 I have to apologize. Turning off segmentation offloading may work as well.
 Just now it fixed VNC issue on bare metal - CentOS 5.2 with Atansic Gigabit
 Ethernet driver (ASUS P5KR) . I gonna try it at DomUs at my earliest convenience.
 
 Boris.
 
 --- On Fri, 4/24/09, Christophe Saout <christophe@xxxxxxxx> wrote:
 
 From: Christophe Saout <christophe@xxxxxxxx>Subject: Re: [Xen-devel] xen.git branch reorg
 To: "Jeremy Fitzhardinge" <jeremy@xxxxxxxx>
 Cc: bderzhavets@xxxxxxxxx, "Xen-devel" <xen-devel@xxxxxxxxxxxxxxxxxxx>, "Ian Campbell" <Ian.Campbell@xxxxxxxxxx>
 Date: Friday, April 24, 2009, 6:39 PM
 
 
 Hi Jeremy,
 > >  In meantime time i see,  that
 2.6.30-rc3&rc2&rc1-tip are
 affected.
 > > Solution is the same as on Solaris xVM Linux DomUs about one
 > > year ago -  is  to disable checksum (nothing else) offloading at
 Linux
 > > DomUs ( CentOS 5.3, Ubuntu 9.04)
 > >
 > > /usr/local/sbin/ethtool -K etho tx off
 >
 > OK, that's a good lead.
 
 Yes, I've been seeing this too (and meant to investigate it before
 claiming there's abug) and I can confirm that turning off segmentation
 offloading "cures" the problem here too.
 
 Now the tcpdump on Dom0 looks interesting.  It repeatedly sees a packet
 with 2880 byte from DomU coming in, which is then dropped and ICMP
 "fragmentation needed" sent back, the DomU resends a 1440 byte packet
 (after some delay), which then goes through, but then the next one is a
 2880 byte one again, and so on.
 
 FYI: My Dom0 is running NAT, in case this is relevant.
 
 Christophe
 
 
 
 _______________________________________________
 Xen-devel mailing list
 Xen-devel@xxxxxxxxxxxxxxxxxxx
 http://lists.xensource.com/xen-devel
 
 | 
 
 _______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
 | 
 |  |