<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">We've had some network problems that were resolved by disabling tcp checksum offloading on all the domUs. Our symptom was we couldn't ssh (or do much else) between two domUs on the same physical host.<DIV><BR class="khtml-block-placeholder"></DIV><DIV>So on each domU we run:</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "> sudo /sbin/ethtool -K eth0 tx off</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><BR></DIV><DIV>Hope this helps!</DIV><DIV>Gabe</DIV><DIV><BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>-- </DIV><DIV>Gabriel M. Schuyler, sysop</DIV><DIV>Intercasting Corporation</DIV><BR class="Apple-interchange-newline"></SPAN> </DIV><BR><DIV><DIV>On Oct 10, 2007, at 12:11 AM, progressdll wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">in a xen environment , i see a lot op dropped packets via netstat -i</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Is this a sign of network problems, or is it normal to see this kind of</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">numbers? i'm not sure how to interprete the data. is this normal, bad,</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">critical. What are your stats on this?</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I guess i have a xen issue of some sort, but not sure what yet</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "># netstat -i</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Kernel Interface table</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Iface <SPAN class="Apple-converted-space"> </SPAN>MTU Met<SPAN class="Apple-converted-space"> </SPAN>RX-OK RX-ERR RX-DRP RX-OVR<SPAN class="Apple-converted-space"> </SPAN>TX-OK TX-ERR TX-DRP</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">TX-OVR Flg</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">eth0 <SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0 53999491<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>6234874<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BMRU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">lo<SPAN class="Apple-converted-space"> </SPAN>16436 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>9247734<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>9247734<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 LRU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">peth0<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0 135679270<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 95455766<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">tap0 <SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>5411876<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 35071803<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BMRU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif-vmdeb<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>35<SPAN class="Apple-converted-space"> </SPAN>0 333350<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif0.0 <SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>6234874<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 53999492<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif6.0 <SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0 55813641<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 98482968<SPAN class="Apple-converted-space"> </SPAN>0 482338<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif6.1 <SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>39<SPAN class="Apple-converted-space"> </SPAN>0 46875771<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif68.0<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BOU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif69.0<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>9349348<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 30571290<SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>3282<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif69.1<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>44<SPAN class="Apple-converted-space"> </SPAN>0 18947590<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif70.0<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>129605<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>460256<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>702<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vif70.1<SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0 <SPAN class="Apple-converted-space"> </SPAN>35<SPAN class="Apple-converted-space"> </SPAN>0 333350<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">xenbr0 <SPAN class="Apple-converted-space"> </SPAN>1500 <SPAN class="Apple-converted-space"> </SPAN>0 46298695<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN>0<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">0 BORU</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">--<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">View this message in context: <A href="http://www.nabble.com/are-dropped-packets-a-sign-of-network-problem--tf4598987.html#a13130626">http://www.nabble.com/are-dropped-packets-a-sign-of-network-problem--tf4598987.html#a13130626</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Sent from the Fedora Xen mailing list archive at Nabble.com.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">--</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Fedora-xen mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:Fedora-xen@redhat.com">Fedora-xen@redhat.com</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="https://www.redhat.com/mailman/listinfo/fedora-xen">https://www.redhat.com/mailman/listinfo/fedora-xen</A></DIV> </BLOCKQUOTE></DIV><BR></DIV></BODY></HTML>