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<body class='hmmessage'><div dir='ltr'>hehe...thanks for the reply, but this post was sent back in 2011...for some reason, a few "older" posts seemed to have arrived today.<div><br></div><div>And agree 100% - We replaced a 2960G with a 4948, and no longer see any drops.</div><div><br><br><div><div id="SkyDrivePlaceholder"></div><hr id="stopSpelling">From: mack.mcbride@viawest.com<br>To: johnelliot67@hotmail.com; cisco-nsp@puck.nether.net<br>Date: Wed, 1 May 2013 13:37:48 -0700<br>Subject: RE: [c-nsp] FW: 2960S drops/packet loss<br><br><style><!--
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--></style><div class="ecxWordSection1"><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">The 2960 has very small buffers.</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">The end solution is a better box since these are queue drops.</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">Replacing the 2960 with a 4948 will solve your problem (although it costs money).</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">Another solution is making sure that most packets are being received on links with</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">the same speed as they are going out so no buffering takes place.</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">Ie. Use all 1G links.</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;"> </span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">LR Mack McBride</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;">Network Architect</span></p><p class="ecxMsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;"> </span></p><div><div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in;"><p class="ecxMsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> cisco-nsp [mailto:cisco-nsp-bounces@puck.nether.net] <b>On Behalf Of </b>John Elliot<br><b>Sent:</b> Thursday, December 22, 2011 4:33 PM<br><b>To:</b> cisco-nsp<br><b>Subject:</b> [c-nsp] FW: 2960S drops/packet loss</span></p></div></div><p class="ecxMsoNormal"> </p><div><div><p class="ecxMsoNormal" style=""><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Re-forward - My original reply seems to have gone missing...</span></p><div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Thanks - Fairly certain we are seeing actual drops (And we are seeing packet-loss across this link)</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Gi1/0/17 is mapped to asic 0/20</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Gi1/0/17 17 17 17 0/20 1 17 17 local Yes Yes</span></p></div></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Port-asic Port Drop Statistics - Summary</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">========================================</span></p></div></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Port 20 TxQueue Drop Stats: 308277833</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">And majority appear to be in Queue 1:</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">(The formatting will probably be screwed up by Hotmail.... apologies)</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Port 20 TxQueue Drop Statistics</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 3</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 1</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 308240408</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 458</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 2</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 37898</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 3</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 91</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 4</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 5</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 6</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Queue 7</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 0 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 1 Frames 0</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> Weight 2 Frames 0</span></p></div></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">So hoping someone can suggest a few tweaks to reduce these drops(And also (more importantly!) the packet-loss)</span></p><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Note - We have other ports on this switch doing far more traffic, but not seeing any loss/drops on these....so I believe it is due to the bursty traffic specific to this trunk port</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Cheers</span></p></div><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><div><p class="ecxMsoNormal" style=""><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><div><div class="ecxMsoNormal" align="center" style="text-align:center;"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"><hr size="2" width="100%" align="center" id="ecxstopSpelling"></span></div><p class="ecxMsoNormal" style=""><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">From: <a href="mailto:tlusty@wayfair.com">tlusty@wayfair.com</a><br>To: <a href="mailto:cisco-nsp@puck.nether.net">cisco-nsp@puck.nether.net</a>; <a href="mailto:johnelliot67@hotmail.com">johnelliot67@hotmail.com</a>; <a href="mailto:andriy.bilous@gmail.com">andriy.bilous@gmail.com</a><br>Date: Thu, 22 Dec 2011 09:08:17 -0500<br>Subject: Re: [c-nsp] 2960S drops/packet loss</span></p><div><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">We’ve run into the same/similar output drop bug (technically a “different” bug, with ID CSCtq86186, but it’s really the same thing). We’re seeing it on a 3750X with 12.2(58)SE. TAC also recommended that we upgrade to 15.2 to fix the issue, but as Andriy noted, it hasn’t been released yet. When I asked them about this, they said that it was actually fixed in 15.0.1(SE1), which was released Dec 2<sup>nd</sup>. We haven’t tested that assertion out yet; we’ve decided to hold off on putting the “fresh out of the oven” IOS on our gear, but if someone else has, and has a good or bad experience we’d be all ears.</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">And just to reiterate what Andriy said, use command ”sh platform port-asic stats drop” to get the true numbers as “sh int <blah>” can’t be trusted. Ensure there are actually drops happening, so you don’t end up chasing a ghost :) </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">-Tom</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><table class="ecxMsoNormalTable" border="0" cellspacing="0" cellpadding="0"><tbody><tr><td style="padding:0in 0in 3.75pt 0in;"><p class="ecxMsoNormal" style=""><b><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#5A2149;text-transform:uppercase;">Tom Lusty</span></b><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#464646;"><br>Senior Systems Engineer </span></p></td><td rowspan="2" style="border:none;border-left:solid #6D6D6D 1.0pt;padding:0in 0in 0in 15.0pt;"><p class="ecxMsoNormal"><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#464646;"><img border="0" width="130" height="55" id="ecx_x005f_x0000_i1025" src="cid:image001.gif@01CE4675.13398DE0" alt="Description: wayfair inc"></span></p></td></tr><tr><td style="padding:0in 33.75pt 0in 0in;"><p class="ecxMsoNormal"><b><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#5A2149;text-transform:uppercase;">Wayfair</span></b><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#464646;"><br>177 Huntington Ave, Suite 6000<br>Boston, MA 02115<br></span><b><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#5A2149;text-transform:uppercase;">P</span></b><span style="font-size:8.5pt;font-family:"Arial","sans-serif";color:#464646;">: 617.502.7026 <br><a href="mailto:tlusty@wayfair.com">tlusty@wayfair.com</a> </span></p></td></tr></tbody></table><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">-----Original Message-----<br>Date: Thu, 22 Dec 2011 13:09:24 +0100</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">From: Andriy Bilous <<a href="mailto:andriy.bilous@gmail.com">andriy.bilous@gmail.com</a>></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">To: John Elliot <<a href="mailto:johnelliot67@hotmail.com">johnelliot67@hotmail.com</a>></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Cc: cisco-nsp <<a href="mailto:cisco-nsp@puck.nether.net">cisco-nsp@puck.nether.net</a>></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Subject: Re: [c-nsp] 2960S drops/packet loss</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Message-ID:</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> <<a href="mailto:CAOnSrb9LO8YffjjwHOPW09SKK+gpKqjWWBK-UFZVtxAivphAdA@mail.gmail.com">CAOnSrb9LO8YffjjwHOPW09SKK+gpKqjWWBK-UFZVtxAivphAdA@mail.gmail.com</a>></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Content-Type: text/plain; charset=ISO-8859-1</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">There is a bug in most of SEs for all stackable models, which makes drop statistics unusable (see CSCso81660 for example - there are lots of BugIDs with same diagnostics and keep in mind "Fixed-in is a lie).</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">Reported numbers aren't realistic and often go both ways - increase and decrease in what appears to be a random manner. sh platform port-asic stats drop should report right value though. So, before you start tweaking, you may want to look further into it and just wait for the sane IOS release. Our SE reported it's fixed in 15.2, which isn't available for download yet.</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">On Thu, Dec 22, 2011 at 4:41 AM, John Elliot <<a href="mailto:johnelliot67@hotmail.com">johnelliot67@hotmail.com</a>> wrote:</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Hi Guys,</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Have a pair of 2960's in a stack, one port(trunk) connects to another DC and we are seeing ~5% packet-lossand large output drops to this DC.</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> #sh interfaces gigabitEthernet 1/0/17 counters errors</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Port ? ? ? ?Align-Err ? ? FCS-Err ? ?Xmit-Err ? ? Rcv-Err ?UnderSize </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ?OutDiscards</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Gi1/0/17 ? ? ? ? ? ?0 ? ? ? ? ? 0 ? ? ? ? ? 0 ? ? ? ? ? 0 ? ? ? ? ?0 ? </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ? ? 182867</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> GigabitEthernet1/0/17 is up, line protocol is up (connected) ?Hardware </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> is Gigabit Ethernet, address is a0cf.5b87.ec11 (bia a0cf.5b87.ec11) </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ?Description: QinQ_to_DC2 ?MTU 1998 bytes, BW 100000 Kbit, DLY 100 </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> usec, ? ? reliability 255/255, txload 41/255, rxload 23/255 </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ?Encapsulation ARPA, loopback not set ?Keepalive set (10 sec) </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ?Full-duplex, 100Mb/s, media type is 10/100/1000BaseTX ?input </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> flow-control is off, output flow-control is unsupported ?ARP type: </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ARPA, ARP Timeout 04:00:00 ?Last input 6d13h, output 00:00:00, output </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> hang never ?Last clearing of "show interface" counters 04:02:15 ?Input </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 183592 </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> ?Queueing strategy: fifo ?Output queue: 0/40 (size/max) ?30 second </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> input rate 9047000 bits/sec, 2075 packets/sec ?30 second output rate </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> 16324000 bits/sec, 2309 packets/sec</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> As you can see, 30sec rate isnt excessive, but as the drops are outdiscards it would appear we are getting hit by the small buffers/microburst issue.</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Done a bit of reasearch, and as we have mls qos configured(Need to as we have to trust dscp markings), we needto look at "tweaking" the buffer allocations on the switch to hopefully mitigate these drops.</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> There appears to be a range of recommendations when it comes to these tweaks - Hoping someone has some suggestions on what to set with "mls qos queue-set output" to alleviate the drops?(start conservative, then apply more aggressive if needed)....and also, does adjusting the buffers require an outage window?</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Our traffic is primarily backup(replication which is very bursty), and </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Internet</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> Thanks in advance.</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> _______________________________________________</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> cisco-nsp mailing list <a href="mailto:?cisco-nsp@puck.nether.net">?cisco-nsp@puck.nether.net</a> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> <a href="https://puck.nether.net/mailman/listinfo/cisco-nsp" target="_blank">https://puck.nether.net/mailman/listinfo/cisco-nsp</a></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">> archive at <a href="http://puck.nether.net/pipermail/cisco-nsp/" target="_blank">http://puck.nether.net/pipermail/cisco-nsp/</a></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">------------------------------</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">_______________________________________________</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";">cisco-nsp mailing list</span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"><a href="mailto:cisco-nsp@puck.nether.net">cisco-nsp@puck.nether.net</a></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"><a href="https://puck.nether.net/mailman/listinfo/cisco-nsp" target="_blank">https://puck.nether.net/mailman/listinfo/cisco-nsp</a></span></p><p class="ecxMsoNormal"><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";"> </span></p></div></div></div></div></div></div></div></div></div></div> </div></body>
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