Hi all, have a strange and recurring network problem with a domU host. Setup: Debian etch is running in domU on Debian etch dom0, xen 3.0.2 The xen network is configured in a bridged mode and there are no firewalls on any of xen domains. Every now and again the domU host losses its connection to the Ethernet network. By loses I mean all network connectivity ceases - from arp to anything else I pass down the NIC. This leaves the host effectively useless as a server. This event does not leave any traces in the logs on the domU or dom0 hosts and happens at seemingly irregular intervals. SNMP graphs dont show anything unusual either. Running the Debian network init script doesn''t fix the problem, the only way to fix it is by restarting the domU host. Im not sure if this is even a xen issue, but perhaps someone here can recognise this or have anything to suggest? Thanks for reading and any tips. JimBow _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi, i also had troubles with networking in xen. These problems disappeared after i disabled TX cheksums on the virtual domain: ethtool -K eth0 tx off you can also do it in the network init script: http://www.shorewall.net/XenMyWay.html -> look under "caution" Greetings, sven On Thu, Feb 14, 2008 at 5:12 PM, JimBow <jimbow@t-n-p.org> wrote:> Hi all, > > have a strange and recurring network problem with a domU host. > Setup: Debian etch is running in domU on Debian etch dom0, xen 3.0.2 > > The xen network is configured in a bridged mode and there are no > firewalls on any of xen domains. > > Every now and again the domU host losses its connection to the > Ethernet network. By loses I mean all network connectivity ceases - > from arp to anything else I pass down the NIC. This leaves the host > effectively useless as a server. > > This event does not leave any traces in the logs on the domU or dom0 > hosts and happens at seemingly irregular intervals. SNMP graphs dont > show anything unusual either. > > Running the Debian network init script doesn''t fix the problem, the > only way to fix it is by restarting the domU host. > > Im not sure if this is even a xen issue, but perhaps someone here > can recognise this or have anything to suggest? > > Thanks for reading and any tips. > > > JimBow > > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
sven waeyenbergh wrote:> i also had troubles with networking in xen. > These problems disappeared after i disabled TX cheksums on the virtual domain: > > ethtool -K eth0 tx offThanks for the pointer, I''m gonna give it a try and report back with the results. And by the way, this doesn''t disable TX checksums, it only disables checksum offloading onto the network card. Thanks all, JimBow _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Zygimantas Skulteckis
2008-Feb-15 10:48 UTC
Re: [Xen-users] intermittent domU network problems
JimBow wrote:> sven waeyenbergh wrote: >> i also had troubles with networking in xen. >> These problems disappeared after i disabled TX cheksums on the >> virtual domain: >> >> ethtool -K eth0 tx off > Thanks for the pointer, I''m gonna give it a try and report back with > the results.Unfortunately disabling hardware checksum offloading did not help, my xen domU has just "fallen" offline again. Does anyone have any other suggestions how to cure domU network problems? Thank you! JimBow _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi Jim, 2008/2/15, JimBow <jimbow@t-n-p.org>:> sven waeyenbergh wrote: > > i also had troubles with networking in xen. > > These problems disappeared after i disabled TX cheksums on the virtual domain: > > > > ethtool -K eth0 tx off > > Thanks for the pointer, I''m gonna give it a try and report back with the > results.Please also check the "age" field in brctl output for the bridge your domU is bound to at the time it loses connectivity, just in case this is the rooot issue. Regards, florian _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
JimBow-2 wrote:> > sven waeyenbergh wrote: >> i also had troubles with networking in xen. >> These problems disappeared after i disabled TX cheksums on the virtual >> domain: >> >> ethtool -K eth0 tx off > Thanks for the pointer, I''m gonna give it a try and report back with the > results. > > And by the way, this doesn''t disable TX checksums, it only disables > checksum offloading onto the network card. > > Thanks all, > > > > JimBow > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users > >Did you ever discover the cause / solution to this problem? We''ve experienced something similar on a couple of our domUs (although only around once every 4 months across around 20 domUs on 3 hosts). Our setup is using debian etch for the dom0 and domU and it''s running the default xen 3.0 packages provided with etch. The hardware is Dell PE860s. Thanks Alex -- View this message in context: http://www.nabble.com/intermittent-domU-network-problems-tp15483436p24303596.html Sent from the Xen - User mailing list archive at Nabble.com. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users