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Weird MTU and TCP retranmission problem
by Sam Stickland 22 Oct '04

22 Oct '04

I haven't seen anything like this before, so I'm hoping someone here could enlighten me. We have a customer that has taken a single co-located server from us. They can download large files from this server to any machine, except the Mac OS X machines at the end of their shared leased line at their office premises. Windows and OS9 machines at this site can download these files fine, as can Mac OS X machines at the end of consumer ADSL lines (offsite). Downloads just stall shortly after starting, which initially appears to an MTU problem. Lowering the MTU on the affect Mac OS X machines fails to solve the problem until the MTU is set to 100 (yes 100) bytes. Strange that the windows machines don't have this problem. These affected Mac OS X machines don't experience this problem if the exact same files are downloaded from a different server in the same datacentre, behind the same router. An ethereal dump of a failed download shows the following: 1.873772 Mac -> Server TCP [TCP Dup ACK 203#32] 7798 > http [ACK] Seq=786 Ack=106053 Win=65535 Len=0 TSV=4064715650 TSER=2370598 1.874145 Server -> Mac HTTP Continuation 1.885515 Mac -> Server TCP [TCP Dup ACK 203#33] 7798 > http [ACK] Seq=786 Ack=106053 Win=65535 Len=0 TSV=4064715650 TSER=2370598 1.885889 Server -> Mac HTTP Continuation 1.897384 Mac -> Server TCP [TCP Dup ACK 203#34] 7798 > http [ACK] Seq=786 Ack=106053 Win=65535 Len=0 TSV=4064715650 TSER=2370598 1.897758 Server -> Mac HTTP Continuation 1.909627 Mac -> Server TCP [TCP Dup ACK 203#35] 7798 > http [ACK] Seq=786 Ack=106053 Win=65535 Len=0 TSV=4064715650 TSER=2370598 1.921996 Mac -> Server TCP [TCP Dup ACK 203#36] 7798 > http [ACK] Seq=786 Ack=106053 Win=65535 Len=0 TSV=4064715650 TSER=2370598 1.933865 Mac -> Server TCP [TCP Dup ACK 203#37] 7798 > http [ACK] Seq=786 Ack=106053 Win=65535 Len=0 TSV=4064715650 TSER=2370598 which leads me unsure as to whether the server is failing to receive the ACKs (hence the ACK retransmission) or whether the Mac is failing to receive the next packet so is retransmitting what it believes to be a lost ACK for the last packet? The server is an HP Proliant running Windows 2003, setup and installed by HP. It's running the built-in windows firewall (ICF), but the effects are the same if this is disabled. Any suggestions of where to continue to look would be very much appreciated. Sam

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RE: Akamai
by Hannigan, Martin 22 Oct '04

22 Oct '04

I can also load pages. route-server>traceroute www.symantec.com Translating "www.symantec.com"...domain server (12.129.192.148) [OK] Type escape sequence to abort. Tracing the route to a568.d.akamai.net (208.254.57.157) 1 mdf1-bi8k-1-ve-93.lax1.attens.net (12.129.193.233) [AS 17233] 4 msec 0 msec 0 msec 2 mdf1-gsr12-1-gig-1-0.lax1.attens.net (12.129.192.237) [AS 17233] 4 msec 0 msec 0 msec 3 gar3-p320.la2ca.ip.att.net (12.122.255.249) [AS 7018] 4 msec 0 msec 0 msec 4 gbr5-p90.la2ca.ip.att.net (12.123.28.193) [AS 7018] 4 msec 0 msec 4 msec 5 tbr1-p013501.la2ca.ip.att.net (12.122.11.137) [AS 7018] 0 msec 0 msec 4 msec 6 ggr2-p300.la2ca.ip.att.net (12.123.29.1) [AS 7018] 0 msec 4 msec 4 msec 7 0.so-5-1-0.BR1.LAX7.ALTER.NET (204.255.168.29) [AS 701] 0 msec 4 msec 0 msec 8 0.so-1-0-0.XL1.LAX7.ALTER.NET (152.63.112.42) [AS 701] 4 msec 0 msec 4 msec 9 0.so-1-0-0.XL1.LAX2.ALTER.NET (152.63.3.185) [AS 701] 0 msec 0 msec 4 msec 10 0.so-4-0-0.WR1.LAX11.ALTER.NET (152.63.115.193) [AS 701] 0 msec 4 msec 4 msec 11 * * * 12 208.254.48.5 [AS 11486] 0 msec 0 msec 4 msec 13 a568.d.akamai.net (208.254.57.157) [AS 11486] 0 msec 0 msec 4 msec -- Martin Hannigan (c) 617-388-2663 VeriSign, Inc. (w) 703-948-7018 Network Engineer IV Operations & Infrastructure hannigan(a)verisign.com > -----Original Message----- > From: owner-nanog(a)merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of > Robert Scott > Sent: Friday, October 22, 2004 9:59 AM > To: nanog(a)nanog.org > Subject: Akamai > > > > Any body else having trouble with Akamai site this AM. > Started about an > hour ago. > > > C:\>tracert www.symantec.com > > Tracing route to a568.d.akamai.net [69.45.79.30] > over a maximum of 30 hops: > > 1 <10 ms <10 ms <10 ms 10.69.98.1 > 2 <10 ms <10 ms <10 ms 68.216.192.17 > 3 16 ms <10 ms <10 ms 205.152.111.94 > 4 <10 ms 16 ms 15 ms axr01mia-7-0-0-1.bellsouth.net > [65.83.237.50] > 5 * * * Request timed out. > 6 * * * Request timed out. > 7 * * * Request timed out. > 8 * * * Request timed out. > > > > > AppleBees says "No Anheuser" > Robert Scott says "NO APPLEBEES!" > Join The Boycott! > > Robert D. Scott > Associate Director > Computer Services and Telecommunications > Network Operations > University of Central Florida > Robert(a)mail.ucf.edu > CSB-310 > 407-823-0662 Voice > 407-823-5476 FAX > 345-0662 Sun-Com > 877-549-5390 Pager >

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The Cidr Report
by cidr-report＠potaroo.net 22 Oct '04

22 Oct '04

This report has been generated at Fri Oct 22 21:44:31 2004 AEST. The report analyses the BGP Routing Table of an AS4637 (Reach) router and generates a report on aggregation potential within the table. Check http://www.cidr-report.org/as4637 for a current version of this report. Recent Table History Date Prefixes CIDR Agg 15-10-04 146802 101029 16-10-04 146969 100417 17-10-04 146823 100433 18-10-04 146815 101032 19-10-04 147048 101156 20-10-04 147106 101176 21-10-04 147089 100943 22-10-04 147143 100940 AS Summary 18222 Number of ASes in routing system 7434 Number of ASes announcing only one prefix 1408 Largest number of prefixes announced by an AS AS7018 : ATTW AT&T WorldNet Services 86713344 Largest address span announced by an AS (/32s) AS721 : DNIC DoD Network Information Center Aggregation Summary The algorithm used in this report proposes aggregation only when there is a precise match using the AS path, so as to preserve traffic transit policies. Aggregation is also proposed across non-advertised address space ('holes'). --- 22Oct04 --- ASnum NetsNow NetsAggr NetGain % Gain Description Table 147045 101011 46034 31.3% All ASes AS18566 746 7 739 99.1% CVAD Covad Communications AS4134 827 181 646 78.1% CHINANET-BACKBONE No.31,Jin-rong Street AS4323 790 219 571 72.3% TWTC Time Warner Telecom AS7018 1408 976 432 30.7% ATTW AT&T WorldNet Services AS7843 497 97 400 80.5% ADELPH-13 Adelphia Corp. AS6197 808 421 387 47.9% BNS-14 BellSouth Network Solutions, Inc AS22773 394 19 375 95.2% CXA Cox Communications Inc. AS27364 411 37 374 91.0% ARMC Armstrong Cable Services AS22909 407 34 373 91.6% CMCS Comcast Cable Communications, Inc. AS701 1231 888 343 27.9% UU UUNET Technologies, Inc. AS6478 415 93 322 77.6% ATTW AT&T WorldNet Services AS1239 946 634 312 33.0% SPRN Sprint AS17676 367 63 304 82.8% JPNIC-JP-ASN-BLOCK Japan Network Information Center AS9929 336 33 303 90.2% CNCNET-CN China Netcom Corp. AS4355 381 99 282 74.0% ERSD EARTHLINK, INC AS4766 532 266 266 50.0% KIXS-AS-KR Korea Telecom AS21502 261 3 258 98.9% ASN-NUMERICABLE NUMERICABLE is a cabled network in France, AS14654 261 6 255 97.7% WAYPOR-3 Wayport AS6140 369 123 246 66.7% IMPSA ImpSat AS15557 343 107 236 68.8% LDCOMNET LDCOM NETWORKS AS2386 847 619 228 26.9% ADCS-1 AT&T Data Communications Services AS25844 244 16 228 93.4% SASMFL-2 Skadden, Arps, Slate, Meagher & Flom LLP AS1221 810 583 227 28.0% ASN-TELSTRA Telstra Pty Ltd AS22291 283 69 214 75.6% CC04 Charter Communications AS6198 429 219 210 49.0% BNS-14 BellSouth Network Solutions, Inc AS721 720 514 206 28.6% DNIC DoD Network Information Center AS4814 206 6 200 97.1% CHINA169-BBN CNCGROUP IP network¡ªChina169 Beijing Broadband Network AS3356 645 446 199 30.9% LEVEL3 Level 3 Communications AS5668 403 211 192 47.6% CIH-12 CenturyTel Internet Holdings, Inc. AS15270 223 37 186 83.4% PDP-14 PaeTec.net -a division of PaeTecCommunications, Inc. Total 16540 7026 9514 57.5% Top 30 total Possible Bogus Routes 24.138.80.0/20 AS11260 AHSICHCL Andara High Speed Internet c/o Halifax Cable Ltd. 24.246.0.0/17 AS7018 ATTW AT&T WorldNet Services 24.246.38.0/24 AS25994 NPGCAB NPG Cable, INC 24.246.128.0/18 AS7018 ATTW AT&T WorldNet Services 64.46.27.0/24 AS8674 NETNOD-IX Netnod Internet Exchange Sverige AB 64.46.34.0/24 AS29393 CLUEFULCOLO-AS AS for Cluefulcolo.net 64.46.63.0/24 AS7850 IHIGHW iHighway.net, Inc. 64.83.96.0/19 AS26956 NETFR NetFree Communications 64.127.0.0/18 AS7018 ATTW AT&T WorldNet Services 69.26.32.0/19 AS17307 VIRTEL-15 Virtela Communications 132.0.0.0/10 AS721 DNIC DoD Network Information Center 137.0.0.0/13 AS721 DNIC DoD Network Information Center 138.136.0.0/13 AS721 DNIC DoD Network Information Center 158.0.0.0/13 AS721 DNIC DoD Network Information Center 192.30.93.0/24 AS17757 HPAUS-AP HP Australia 192.30.94.0/24 AS17757 HPAUS-AP HP Australia 192.30.127.0/24 AS719 LANLINK Elisa Oyj 192.40.105.0/24 AS5515 SONERA-GLOBAL-IP Sonera Solution Autonomous System 192.44.0.0/19 AS702 AS702 MCI EMEA - Commercial IP service provider in Europe 192.70.164.0/24 AS25689 NRCC-2 National Research Council of Canada 192.81.182.0/24 AS719 LANLINK Elisa Oyj 192.81.183.0/24 AS719 LANLINK Elisa Oyj 192.81.184.0/24 AS719 LANLINK Elisa Oyj 192.119.135.0/24 AS270 NASA National Aeronautics and Space Administration 192.124.252.0/22 AS680 DFN-IP service G-WiN 192.133.6.0/24 AS4004 GLOBALONE-EQUANT-UK Equant UK & Greece Autonomous System 192.135.50.0/24 AS7018 ATTW AT&T WorldNet Services 192.153.144.0/21 AS721 DNIC DoD Network Information Center 192.172.0.0/19 AS721 DNIC DoD Network Information Center 192.188.208.0/20 AS721 DNIC DoD Network Information Center 192.243.32.0/23 AS2044 PALINA Palin Aquisitions Inc. 196.2.95.0/24 AS8668 TELONE-AS TelOne Zimbabwe P/L 198.23.26.0/24 AS4390 BELLAT-7 Bell Atlantic, Inc. 198.97.72.0/21 AS721 DNIC DoD Network Information Center 198.97.80.0/20 AS721 DNIC DoD Network Information Center 198.97.88.0/24 AS89 NUSC-1 Naval Underwater Systems Center 198.97.240.0/20 AS721 DNIC DoD Network Information Center 198.97.247.0/24 AS3475 DEPART-52 Department of the Navy 198.101.4.0/22 AS721 DNIC DoD Network Information Center 198.136.32.0/20 AS19329 MCBCC Martin County Board of County Commissioners 198.144.32.0/19 AS3998 CITY CityNet, Inc. 198.161.87.0/24 AS6539 GTGR GT Group Telecom Services Corp. 198.161.165.0/24 AS852 AGTA Telus Advanced Communications 198.163.155.0/24 AS684 MRN Manitoba Regional Network 198.167.0.0/16 AS7456 INS-51 Interhop Network SERVICES Inc. 198.167.163.0/24 AS15290 ACCA-2 Allstream Corp. Corporation Allstream 198.168.0.0/16 AS701 UU UUNET Technologies, Inc. 198.169.0.0/16 AS803 SASK SaskTel 198.232.133.0/24 AS23075 SKOTOS Skotos Tech, Inc 199.10.0.0/16 AS721 DNIC DoD Network Information Center 199.60.0.0/20 AS271 UBC-3 University of British Columbia 199.96.44.0/23 AS19092 360NE-1 360Networks (USA) Inc. 199.96.46.0/24 AS19092 360NE-1 360Networks (USA) Inc. 199.114.0.0/18 AS568 DISOUN DISO-UNRRA 199.114.0.0/21 AS721 DNIC DoD Network Information Center 199.114.128.0/18 AS721 DNIC DoD Network Information Center 199.114.130.0/24 AS721 DNIC DoD Network Information Center 199.114.132.0/24 AS721 DNIC DoD Network Information Center 199.114.134.0/24 AS1913 DLA-8 Defense Logistics Agency 199.114.136.0/24 AS1913 DLA-8 Defense Logistics Agency 199.114.138.0/24 AS721 DNIC DoD Network Information Center 199.114.140.0/24 AS3544 DISAUN DISA/UNRRA 199.114.142.0/24 AS721 DNIC DoD Network Information Center 199.114.144.0/24 AS721 DNIC DoD Network Information Center 199.114.148.0/24 AS721 DNIC DoD Network Information Center 199.114.150.0/24 AS721 DNIC DoD Network Information Center 199.114.152.0/24 AS1913 DLA-8 Defense Logistics Agency 199.114.154.0/24 AS1733 ADP-41 AF DDN PMO 199.114.156.0/24 AS1913 DLA-8 Defense Logistics Agency 199.114.160.0/24 AS1733 ADP-41 AF DDN PMO 199.120.32.0/19 AS16582 NXLI NEXTLEVEL INTERNET, INC. 199.121.0.0/16 AS721 DNIC DoD Network Information Center 199.123.0.0/18 AS721 DNIC DoD Network Information Center 199.123.16.0/20 AS721 DNIC DoD Network Information Center 199.123.80.0/21 AS721 DNIC DoD Network Information Center 199.189.32.0/19 AS7332 IQUEST IQuest Internet 199.197.8.0/22 AS21814 PARSON-18 Parsons Corp. 199.202.0.0/16 AS701 UU UUNET Technologies, Inc. 200.26.216.0/24 AS10834 Telefonica Data Argentina S.A. 202.70.28.0/24 AS4515 ERX-STAR Star Internet Services Ltd. 202.73.128.0/22 AS4058 LINKAGENET-AP CPCNet Hong Kong Ltd. 202.93.0.0/20 AS4134 CHINANET-BACKBONE No.31,Jin-rong Street 202.133.3.0/24 AS9335 CIP-JAPAN-AS-AP ATT IPlus 202.164.224.0/19 AS7599 IPXC-AS-AP IP Exchange 203.32.4.0/23 AS7617 203.62.0.0/17 AS7572 AARNET-ACT-RNO Australian Academic and Reasearch Network (AARNet) 203.84.192.0/19 AS17433 PHILWEB-AP PhilWeb.Com, Inc. 203.84.192.0/20 AS17433 PHILWEB-AP PhilWeb.Com, Inc. 203.84.208.0/20 AS17433 PHILWEB-AP PhilWeb.Com, Inc. 203.170.14.0/23 AS6648 ASN-SKYINTERNET ASs peering of Sky Internet 203.210.69.0/24 AS17536 PRODIGY-AS-AP Prodidgy Telecommunications 204.154.125.0/24 AS3952 TELLAB-1 TELLABS Operations, Inc. 204.154.126.0/24 AS3952 TELLAB-1 TELLABS Operations, Inc. 204.154.127.0/24 AS3952 TELLAB-1 TELLABS Operations, Inc. 204.194.110.0/23 AS30653 EXOBI Exobit Networks Inc. 205.150.0.0/15 AS701 UU UUNET Technologies, Inc. 205.159.72.0/24 AS1660 ANSCOM-5 ANS Communications 206.167.57.0/24 AS376 RISQR-3 Reseau Interordinateurs Scientique Quebecois (RISQ) 206.191.64.0/18 AS15290 ACCA-2 Allstream Corp. Corporation Allstream 206.251.69.0/24 AS27429 TIL-33 Telesat International Ltd. 206.253.190.0/23 AS8123 POLYBA Polybase 207.47.254.0/24 AS701 UU UUNET Technologies, Inc. 207.231.96.0/19 AS11194 NUNETI NuNet Inc 208.81.187.0/24 AS19194 SNL-8 Sentris Network LLC 209.172.0.0/18 AS7770 TRTI Triton Technologies, Inc. 209.205.69.0/24 AS21578 Universidad autonoma de Bucaramanga 209.205.70.0/24 AS21578 Universidad autonoma de Bucaramanga 209.205.81.0/24 AS15066 SkyNet de Colombia S.A. 209.205.82.0/24 AS15066 SkyNet de Colombia S.A. 209.205.84.0/24 AS15066 SkyNet de Colombia S.A. 209.213.32.0/19 AS10629 INS-52 Inter-Pacific Network Services 209.213.48.0/24 AS10629 INS-52 Inter-Pacific Network Services 209.213.49.0/24 AS10629 INS-52 Inter-Pacific Network Services 209.213.50.0/24 AS10629 INS-52 Inter-Pacific Network Services 209.251.0.0/19 AS11036 SISCOM-1 SISCOM, Inc 210.4.0.0/18 AS6648 ASN-SKYINTERNET ASs peering of Sky Internet 210.4.0.0/19 AS6648 ASN-SKYINTERNET ASs peering of Sky Internet 210.4.32.0/19 AS6648 ASN-SKYINTERNET ASs peering of Sky Internet 216.37.110.0/23 AS4264 CERFN California Education and Research Federation Network 216.96.128.0/18 AS7018 ATTW AT&T WorldNet Services 216.145.130.0/23 AS11937 TRXI TRX Inc. 216.145.132.0/22 AS11937 TRXI TRX Inc. 216.145.156.0/24 AS20304 JIS-32 JVLNET Internet Services 216.145.158.0/24 AS20304 JIS-32 JVLNET Internet Services 216.145.176.0/21 AS20304 JIS-32 JVLNET Internet Services 216.145.177.0/24 AS20304 JIS-32 JVLNET Internet Services 216.145.178.0/24 AS20304 JIS-32 JVLNET Internet Services 216.145.184.0/21 AS10758 INWAVE INWave Internet, Inc 216.145.200.0/21 AS20304 JIS-32 JVLNET Internet Services 216.186.151.0/24 AS3356 LEVEL3 Level 3 Communications 216.186.152.0/21 AS3356 LEVEL3 Level 3 Communications 216.186.160.0/23 AS3356 LEVEL3 Level 3 Communications 216.186.164.0/22 AS3356 LEVEL3 Level 3 Communications 216.186.192.0/22 AS3356 LEVEL3 Level 3 Communications 216.186.198.0/23 AS3356 LEVEL3 Level 3 Communications 216.186.248.0/23 AS3356 LEVEL3 Level 3 Communications Please see http://www.cidr-report.org for the full report ------------------------------------ Copies of this report are mailed to: nanog(a)merit.edu eof-list(a)ripe.net apops(a)apops.net routing-wg(a)ripe.net afnog(a)afnog.org swinog(a)swinog.ch

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IP Address Tracking?
by Jason Slagle 21 Oct '04

21 Oct '04

A few years ago, it seemed freeipdb and NorthStar were the way to go. freeipdb.org is DOA, and NorthStar's last development note is over a year ago with CVS unreachable. Are these two projects dead? If do, what are people using now. Thanks, Jason -- Jason Slagle - CCNP - CCDP /"\ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \ / ASCII Ribbon Campaign . X - NO HTML/RTF in e-mail . / \ - NO Word docs in e-mail .

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Re: BCP38 making it work, solving problems
by Fergie (Paul Ferguson) 21 Oct '04

21 Oct '04

It's better than a sharp stick in the eye, I'll tell ya, lad. Listen to me: It's called a "best current practice" for a reason -- people should do it. Not sit and around and endlessly discuss it (we've already done that a thousand times). I wrote it, I stand beside it. I'm sick of hearing why people haven't implemented it yet -- it's almost five years later and there's simply no excuse. It's sickening. - fergie Ref: ftp://ftp.rfc-editor.org/in-notes/bcp/bcp38.txt -- Sean Donelan <sean(a)donelan.com> wrote: But BCP38 doesn't immediately help the ISP. -- "Fergie", a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawg(a)netzero.net or fergdawg(a)sbcglobal.net

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Contact for ibmt.btconnect.com
by Steve Wright - EliteUKServe 21 Oct '04

21 Oct '04

Hi all, Could a BT Connect/ BT mail server admin contact me ASAP please with regard to one of your mail server/ clusters rejecting our mail. If anyone already has a contact, could you please forward as I am struggling to find anyone within BT who knows who's who. TIA Best Regards, Steve Wright EliteUKServe EMail: steve.wright(a)eliteukserve.net Tel: +44 (0) 870 250 7611

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in memoriam
by Randy Bush 21 Oct '04

21 Oct '04

abha ahuja died on this day in 2001 randy

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Cisco etherchannel question
by william(at)elan.net 21 Oct '04

21 Oct '04

Hi, I have etherchannel setup between cisco 7500 router and 5500 switch. For data going from 7500 router everything seems to be ok and data is well split between four interfaces with about 1/4th sent to each one (about 40% utilization each right now). But for data going from 5500 switch the split appears to be that one interface has 100% utilization while another one is 20% and others are less then 10%. So its not really splitting data on random basis to each interface and uses other interfaces as overflow after the main one. I don't like this as the one interface that is 100% full appears to sometimes be dropping packets on either switch or cisco router side. I'm wondering what I can do to force 5500 to use etherchannel in similar way cisco 7500 does? -- William Leibzon Elan Networks william(a)elan.net

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MCI problems - LA?
by Matt Bazan 21 Oct '04

21 Oct '04

anyone else seeing problems with mci in LA? apparently, from the rumors i've heard, they've had one or several of their main fiber links cut..

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Major maintenance in Level3?
by Wei Keong 21 Oct '04

21 Oct '04

Hi, We from our upstreams that Level3 (AS3356) is having a major maintenance from end of Sep to end of Oct. Do you guys have any info about this? Thanks, Wei Keong Pacific Internet Singapore (AS4628)

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