ajm786 Posted March 1, 2005 CID Share Posted March 1, 2005 Thanks for having this useful forum; hopefully it will help me solve this issue. I have a Covad T1 connection, with a Netopia router and a Netscreen firewall, all supplied by Covad. Covad administers both of them, so I have no access. Here is the problem. At random intervals, during the day, the internet connection will just drop. No ping commands work, as there is no IP address (using DHCP from the router). However, the actual physical connection does not drop. Let me explain a bit further. This is how I am setup: T1 Line > Covad router > Netscreen firewall > switch/hub (distribution) I have 3 computers NOT behind the firewall. They are connected directly to the Covad router. When the connection drops, these computers work perfectly fine. Also, when the internet does work, I ping the firewall. I get massive packet loss: Reply from 68.164.103.130: bytes=32 time=407ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time=16ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Request timed out. Request timed out. Request timed out. Reply from 68.164.103.130: bytes=32 time=391ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Request timed out. Request timed out. Request timed out. Request timed out. Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Reply from 68.164.103.130: bytes=32 time=15ms TTL=64 Reply from 68.164.103.130: bytes=32 time<10ms TTL=64 Ping statistics for 68.164.103.130: Quote Link to comment Share on other sites More sharing options...
VanBuren Posted March 1, 2005 CID Share Posted March 1, 2005 hey ajm786 and welcome to the forum I do not know much about routers, but you can run this test and see if it can find anything http://nitro.ucsc.edu/ copy all text from More info and Statistic and paste it here VanBuren Quote Link to comment Share on other sites More sharing options...
ajm786 Posted March 1, 2005 Author CID Share Posted March 1, 2005 Here's what I get: TCP/Web100 Network Diagnostic Tool v5.3.3a click START to begin Another client is currently being served, your test will begin within 45 seconds Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done running 10s outbound test (client to server) . . . . . 631.78Kb/s running 10s inbound test (server to client) . . . . . . 1.39Mb/s Your PC is connected to a Cable/DSL modem Information: Other network traffic is congesting the link click START to re-test WEB100 Enabled Statistics: Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done running 10s outbound test (client to server) . . . . . 631.78Kb/s running 10s inbound test (server to client) . . . . . . 1.39Mb/s ------ Client System Details ------ OS data: Name = Windows 2000, Architecture = x86, Version = 5.0 Java data: Vendor = Sun Microsystems Inc., Version = 1.4.2_07 ------ Web100 Detailed Analysis ------ Cable modem/DSL/T1 link found. Link set to Full Duplex mode Information: throughput is limited by other network traffic. Good network cable(s) found Normal duplex operation found. Web100 reports the Round trip time = 138.87 msec; the Packet size = 1460 Bytes; and There were 11 packets retransmitted, 181 duplicate acks received, and 175 SACK blocks received The connection was idle 0 seconds (0%) of the time This connection is network limited 99.98% of the time. Contact your local network administrator to report a network problem Contact your local network admin and report excessive packet reordering Web100 reports TCP negotiated the optional Performance Settings to: RFC 2018 Selective Acknowledgment: ON RFC 896 Nagle Algorithm: ON RFC 3168 Explicit Congestion Notification: OFF RFC 1323 Time Stamping: OFF RFC 1323 Window Scaling: OFF Packet size is preserved End-to-End Server IP addresses are preserved End-to-End Client IP addresses are preserved End-to-End WEB100 Kernel Variables: Client: localhost/127.0.0.1 AckPktsIn: 1206 AckPktsOut: 0 BytesRetrans: 16060 CongAvoid: 969 CongestionOverCount: 0 CongestionSignals: 6 CountRTT: 1014 CurCwnd: 21900 CurMSS: 1460 CurRTO: 330 CurRwinRcvd: 65535 CurRwinSent: 5840 CurSsthresh: 16060 DSACKDups: 0 DataBytesIn: 0 DataBytesOut: 1775360 DataPktsIn: 0 DataPktsOut: 1216 DupAcksIn: 181 ECNEnabled: 0 FastRetran: 6 MaxCwnd: 40880 MaxMSS: 1460 MaxRTO: 400 MaxRTT: 210 MaxRwinRcvd: 65535 MaxRwinSent: 5840 MaxSsthresh: 20440 MinMSS: 1460 MinRTO: 330 MinRTT: 100 MinRwinRcvd: 24655 MinRwinSent: 5840 NagleEnabled: 1 OtherReductions: 0 PktsIn: 1206 PktsOut: 1216 PktsRetrans: 11 X_Rcvbuf: 103424 RcvWinScale: 2147483647 SACKEnabled: 3 SACKsRcvd: 175 SendStall: 0 SlowStart: 45 SampleRTT: 120 SmoothedRTT: 110 X_Sndbuf: 103424 SndWinScale: 2147483647 SndLimTimeRwin: 0 SndLimTimeCwnd: 10139112 SndLimTimeSender: 2504 SndLimTransRwin: 0 SndLimTransCwnd: 1 SndLimTransSender: 1 SndLimBytesRwin: 0 SndLimBytesCwnd: 1775360 SndLimBytesSender: 0 SubsequentTimeouts: 0 SumRTT: 140810 Timeouts: 0 TimestampsEnabled: 0 WinScaleRcvd: 2147483647 WinScaleSent: 2147483647 DupAcksOut: 0 StartTimeUsec: 638953 Duration: 10147731 c2sData: 2 c2sAck: 2 s2cData: 2 s2cAck: 2 half_duplex: 0 link: 100 congestion: 1 bad_cable: 0 mismatch: 0 spd: 0.00 bw: 1.14 loss: 0.004934211 avgrtt: 138.87 waitsec: 0.00 timesec: 10.00 order: 0.1501 rwintime: 0.0000 sendtime: 0.0002 cwndtime: 0.9998 rwin: 0.5000 swin: 0.7891 cwin: 0.3119 rttsec: 0.138866 Sndbuf: 103424 Checking for mismatch condition (cwndtime > .3) [0.99>.3], (MaxSsthresh > 0) [20440>0], (PktsRetrans/sec > 2) [1.1>2], (estimate > 2) [1.14>2] Checking for mismatch on uplink (speed > 50 [0>50], (xmitspeed < 5) [0.63<5] (rwintime > .9) [0>.9], (loss < .01) [0.00<.01] Checking for excessive errors condition (loss/sec > .15) [4.93>.15], (cwndtime > .6) [0.99>.6], (loss < .01) [0.00<.01], (MaxSsthresh > 0) [20440>0] Checking for 10 Mbps link (speed < 9.5) [0<9.5], (speed > 3.0) [0>3.0] (xmitspeed < 9.5) [0.63<9.5] (loss < .01) [0.00<.01], (mylink > 0) [3.0>0] Checking for Wireless link (sendtime = 0) [2.0E=0], (speed < 5) [0<5] (Estimate > 50 [1.14>50], (Rwintime > 90) [0>.90] (RwinTrans/CwndTrans = 1) [0/1=1], (mylink > 0) [3.0>0] Checking for DSL/Cable Modem link (speed < 2) [0<2], (SndLimTransSender = 0) [1=0] (SendTime = 0) [2.0E-4=0], (mylink > 0) [3.0>0] Checking for half-duplex condition (rwintime > .95) [0>.95], (RwinTrans/sec > 30) [0>30], (SenderTrans/sec > 30) [0.1>30], OR (mylink <= 10) [3.0<=10] Checking for congestion (cwndtime > .02) [0.99>.02], (mismatch = 0) [0=0] (MaxSsthresh > 0) [20440>0] estimate = 1.14 based on packet size = 11Kbits, RTT = 138.87msec, and loss = 0.004934211 The theoretical network limit is 1.14 Mbps The NDT server has a 101.0 KByte buffer which limits the throughput to 5.68 Mbps Your PC/Workstation has a 63.0 KByte buffer which limits the throughput to 3.60 Mbps The network based flow control limits the throughput to 2.24 Mbps Client Data reports link is 'T1', Client Acks report link is 'T1' Server Data reports link is 'T1', Server Acks report link is 'T1' Quote Link to comment Share on other sites More sharing options...
Nolder Posted April 20, 2005 CID Share Posted April 20, 2005 In case you havent figured this problem out yet. Netopia released a batch of the 4622-XL model routers most of which were sold to covad T1 clients that would periodicaly and for no apparent reason drop the LAN connection from the router to all connected devices. im not sure when you started haveing this problem but for quite some time Covad did not have any knoledge of this either that or werent willing to admit to it, any way when you would contact covad to report the problem they would run the usual test's and the router would check out fine so they would tell you that it was a problem on your end. The router checked out ok because it was not dropping WAN olny LAN so from what they could tell the router was functioning correctly. The olny way to fix this problem and it was olny temporary was to power cycle the modem, but like I said this olny temporarily fixed the problem. Any way if you are still haveing this problem contact covad again and tell them that your Netopia 4622-XL is frequently dropping the LAN connection and that any test they may run will not show this. with that they should have a new router at your doorstep with in about 4 hours. and if I recall the bad batch of routers had a serial number starting with 933 or something like that. Covad now knows about this problem and will either replace your router with the same make and model just one that does not malfunction or they will swap it out for the Seimens 5940 buisness T1 gateway, At least thats what they did when my Netopia 4622-XL-T ceased to function properly. Quote Link to comment Share on other sites More sharing options...
firewallrus Posted January 4, 2006 CID Share Posted January 4, 2006 Just in case anyone is still interested... I've seen similar problems. Quote Link to comment Share on other sites More sharing options...
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