Re: [squid-users] Connection reset by peer

Hi John,

As Amos mentioned, it would be great to see http payload of the packets
(use -Afnn switches for this). Also traffic on proxy itself is more
interesting.
IIRC, 502 status code means that your proxy has some issues when reading
data from origin server. Do you see anything suspicious in cache.log?

Best wishes,
Pavel

On 10/09/2013 09:00 AM, John Kenyon wrote:
>> What makes you think that? HTTP/1.1 does not require FIN and as far as I can
>> see those URL responses all contain explicit Connection:keep-alive.
>>
>> The content of those packets between Squid and server may shed some more
>> light on it. Try saving a full packet dump and viewing it with wireshark.
>>
>> Amos
>
> Hi Amos,
>
> I have rolled back to Squid 3.1.23 and all is working as expected now, but I would like to still find out what in Squid 3.3.x is causing this... I will need to run up another instance of squid to perform further testing.
>
> The reason why I thought it might be related to the FIN packet is when it does work it seems the server is able to send the final packet before the reset packet.
>
> Here is the full tcpdump... I can install wireshark if required...
>
> NOT WORKING
>
> # tcpdump -i eth0 dst 66.151.79.155
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
> 16:53:53.462042 IP proxyserver.33784 > 66.151.79.155.http: S 264441315:264441315(0) win 5840 <mss 1460,sackOK,timestamp 447447258 0,nop,wscale 8>
> 16:53:53.665606 IP proxyserver.33784 > 66.151.79.155.http: . ack 258927824 win 23 <nop,nop,timestamp 447447462 0>
> 16:53:53.666037 IP proxyserver.33784 > 66.151.79.155.http: P 0:636(636) ack 1 win 23 <nop,nop,timestamp 447447462 0>
> 16:53:53.666217 IP proxyserver.33784 > 66.151.79.155.http: P 636:711(75) ack 1 win 23 <nop,nop,timestamp 447447462 0>
> 16:53:53.903639 IP proxyserver.33784 > 66.151.79.155.http: . ack 327 win 27 <nop,nop,timestamp 447447700 4801001>
> 16:53:54.028623 IP proxyserver.33784 > 66.151.79.155.http: P 711:1363(652) ack 327 win 27 <nop,nop,timestamp 447447825 4801001>
>
> # tcpdump -i eth0 src 66.151.79.155
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
> 16:55:17.007426 IP 66.151.79.155.http > proxyserver.34334: S 2581779361:2581779361(0) ack 350474126 win 16384 <mss 1380,nop,wscale 0,nop,nop,timestamp 0 0,nop,nop,sackOK>
> 16:55:17.225169 IP 66.151.79.155.http > proxyserver.34334: . ack 714 win 64822 <nop,nop,timestamp 4801834 447530601>
> 16:55:26.115901 IP 66.151.79.155.http > proxyserver.34334: P 1:327(326) ack 714 win 64822 <nop,nop,timestamp 4801924 447530601>
> 16:55:26.552923 IP 66.151.79.155.http > proxyserver.34334: . ack 1366 win 64170 <nop,nop,timestamp 4801928 447540018>
> 16:55:26.943813 IP 66.151.79.155.http > proxyserver.34334: R 327:327(0) ack 1366 win 0
>
>
> WORKING
>
> # tcpdump -i eth0 dst 66.151.79.155
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
> 17:07:28.092131 IP proxyserver.53294 > 66.151.79.155.http: S 1133726612:1133726612(0) win 5840 <mss 1460,sackOK,timestamp 448261838 0,nop,wscale 8>
> 17:07:31.091991 IP proxyserver.53294 > 66.151.79.155.http: S 1133726612:1133726612(0) win 5840 <mss 1460,sackOK,timestamp 448264838 0,nop,wscale 8>
> 17:07:31.295283 IP proxyserver.53294 > 66.151.79.155.http: . ack 1237499326 win 23 <nop,nop,timestamp 448265041 0>
> 17:07:31.295597 IP proxyserver.53294 > 66.151.79.155.http: P 0:636(636) ack 1 win 23 <nop,nop,timestamp 448265041 0>
> 17:07:31.295710 IP proxyserver.53294 > 66.151.79.155.http: P 636:711(75) ack 1 win 23 <nop,nop,timestamp 448265041 0>
> 17:07:31.529730 IP proxyserver.53294 > 66.151.79.155.http: . ack 327 win 27 <nop,nop,timestamp 448265275 4809178>
> 17:07:31.680187 IP proxyserver.53294 > 66.151.79.155.http: P 711:1363(652) ack 327 win 27 <nop,nop,timestamp 448265426 4809178>
> 17:07:31.882188 IP proxyserver.53294 > 66.151.79.155.http: F 1363:1363(0) ack 328 win 27 <nop,nop,timestamp 448265628 4809181>
> 17:07:31.882228 IP proxyserver.53320 > 66.151.79.155.http: S 1131177905:1131177905(0) win 5840 <mss 1460,sackOK,timestamp 448265628 0,nop,wscale 8>
> 17:07:32.076585 IP proxyserver.53320 > 66.151.79.155.http: . ack 3528185504 win 23 <nop,nop,timestamp 448265822 0>
> 17:07:32.076867 IP proxyserver.53320 > 66.151.79.155.http: P 0:652(652) ack 1 win 23 <nop,nop,timestamp 448265822 0>
> 17:07:32.423790 IP proxyserver.53320 > 66.151.79.155.http: . ack 136 win 27 <nop,nop,timestamp 448266169 4809187>
> 17:07:32.425107 IP proxyserver.53320 > 66.151.79.155.http: . ack 1504 win 38 <nop,nop,timestamp 448266171 4809187>
> 17:07:32.618487 IP proxyserver.53320 > 66.151.79.155.http: . ack 2872 win 49 <nop,nop,timestamp 448266364 4809189>
> 17:07:32.618532 IP proxyserver.53320 > 66.151.79.155.http: . ack 4240 win 60 <nop,nop,timestamp 448266364 4809189>
> 17:07:32.619921 IP proxyserver.53320 > 66.151.79.155.http: . ack 5608 win 70 <nop,nop,timestamp 448266365 4809189>
> 17:07:32.619976 IP proxyserver.53320 > 66.151.79.155.http: . ack 6976 win 81 <nop,nop,timestamp 448266365 4809189>
> 17:07:32.813212 IP proxyserver.53320 > 66.151.79.155.http: . ack 8344 win 92 <nop,nop,timestamp 448266559 4809190>
> 17:07:32.813261 IP proxyserver.53320 > 66.151.79.155.http: . ack 9712 win 102 <nop,nop,timestamp 448266559 4809190>
> 17:07:32.813381 IP proxyserver.53320 > 66.151.79.155.http: . ack 11080 win 113 <nop,nop,timestamp 448266559 4809190>
> 17:07:32.813503 IP proxyserver.53320 > 66.151.79.155.http: . ack 12448 win 124 <nop,nop,timestamp 448266559 4809190>
> 17:07:32.814275 IP proxyserver.53320 > 66.151.79.155.http: . ack 13816 win 134 <nop,nop,timestamp 448266560 4809190>
> 17:07:32.814372 IP proxyserver.53320 > 66.151.79.155.http: . ack 15184 win 145 <nop,nop,timestamp 448266560 4809190>
> 17:07:32.814485 IP proxyserver.53320 > 66.151.79.155.http: . ack 16528 win 156 <nop,nop,timestamp 448266560 4809190>
> 17:07:33.007797 IP proxyserver.53320 > 66.151.79.155.http: . ack 16536 win 156 <nop,nop,timestamp 448266753 4809192>
> 17:07:33.010420 IP proxyserver.53320 > 66.151.79.155.http: . ack 17904 win 166 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010536 IP proxyserver.53320 > 66.151.79.155.http: . ack 19272 win 177 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010653 IP proxyserver.53320 > 66.151.79.155.http: . ack 20640 win 188 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010767 IP proxyserver.53320 > 66.151.79.155.http: . ack 22008 win 198 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010887 IP proxyserver.53320 > 66.151.79.155.http: . ack 23376 win 209 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010969 IP proxyserver.53320 > 66.151.79.155.http: . ack 24313 win 220 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010980 IP proxyserver.53320 > 66.151.79.155.http: . ack 24315 win 220 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.010988 IP proxyserver.53320 > 66.151.79.155.http: . ack 24320 win 220 <nop,nop,timestamp 448266756 4809192>
> 17:07:33.011354 IP proxyserver.53320 > 66.151.79.155.http: F 652:652(0) ack 24320 win 220 <nop,nop,timestamp 448266757 4809192>
> 17:07:33.205256 IP proxyserver.53320 > 66.151.79.155.http: . ack 24321 win 220 <nop,nop,timestamp 448266951 4809194>
>
>
> # tcpdump -i eth0 src 66.151.79.155
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
> 16:54:47.940285 IP 66.151.79.155.http > proxyserver.34230: S 3453084812:3453084812(0) ack 327244699 win 16384 <mss 1380,nop,wscale 0,nop,nop,timestamp 0 0,nop,nop,sackOK>
> 16:54:48.136907 IP 66.151.79.155.http > proxyserver.34230: . ack 714 win 64822 <nop,nop,timestamp 4801543 447501539>
> 16:54:48.222782 IP 66.151.79.155.http > proxyserver.34230: P 1:327(326) ack 714 win 64822 <nop,nop,timestamp 4801544 447501539>
> 16:54:48.567137 IP 66.151.79.155.http > proxyserver.34230: F 327:327(0) ack 714 win 64822 <nop,nop,timestamp 4801548 447502015>
> 16:54:48.587248 IP 66.151.79.155.http > proxyserver.34230: R 328:328(0) ack 1366 win 0
> 16:54:48.770802 IP 66.151.79.155.http > proxyserver.34232: S 2462277382:2462277382(0) ack 325513436 win 16384 <mss 1380,nop,wscale 0,nop,nop,timestamp 0 0,nop,nop,sackOK>
> 16:54:49.166166 IP 66.151.79.155.http > proxyserver.34232: P 1:136(135) ack 653 win 64883 <nop,nop,timestamp 4801554 447502360>
> 16:54:49.167354 IP 66.151.79.155.http > proxyserver.34232: . 136:1504(1368) ack 653 win 64883 <nop,nop,timestamp 4801554 447502360>
> 16:54:49.369492 IP 66.151.79.155.http > proxyserver.34232: . 1504:2872(1368) ack 653 win 64883 <nop,nop,timestamp 4801555 447502959>
> 16:54:49.370254 IP 66.151.79.155.http > proxyserver.34232: . 2872:4240(1368) ack 653 win 64883 <nop,nop,timestamp 4801555 447502959>
> 16:54:49.370836 IP 66.151.79.155.http > proxyserver.34232: . 4240:5608(1368) ack 653 win 64883 <nop,nop,timestamp 4801555 447502960>
> 16:54:49.370953 IP 66.151.79.155.http > proxyserver.34232: . 5608:6976(1368) ack 653 win 64883 <nop,nop,timestamp 4801555 447502960>
> 16:54:49.573650 IP 66.151.79.155.http > proxyserver.34232: . 6976:8344(1368) ack 653 win 64883 <nop,nop,timestamp 4801558 447503162>
> 16:54:49.573720 IP 66.151.79.155.http > proxyserver.34232: P 8344:9712(1368) ack 653 win 64883 <nop,nop,timestamp 4801558 447503162>
> 16:54:49.573836 IP 66.151.79.155.http > proxyserver.34232: . 9712:11080(1368) ack 653 win 64883 <nop,nop,timestamp 4801558 447503163>
> 16:54:49.573955 IP 66.151.79.155.http > proxyserver.34232: . 11080:12448(1368) ack 653 win 64883 <nop,nop,timestamp 4801558 447503163>
> 16:54:49.574188 IP 66.151.79.155.http > proxyserver.34232: . 12448:13816(1368) ack 653 win 64883 <nop,nop,timestamp 4801558 447503163>
> 16:54:49.574773 IP 66.151.79.155.http > proxyserver.34232: . 13816:15184(1368) ack 653 win 64883 <nop,nop,timestamp 4801558 447503163>
> 16:54:49.575470 IP 66.151.79.155.http > proxyserver.34232: P 15184:16528(1344) ack 653 win 64883 <nop,nop,timestamp 4801558 447503163>
> 16:54:49.786877 IP 66.151.79.155.http > proxyserver.34232: P 16528:16536(8) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788255 IP 66.151.79.155.http > proxyserver.34232: . 16536:17904(1368) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788371 IP 66.151.79.155.http > proxyserver.34232: . 17904:19272(1368) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788496 IP 66.151.79.155.http > proxyserver.34232: . 20640:22008(1368) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788611 IP 66.151.79.155.http > proxyserver.34232: . 22008:23376(1368) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788697 IP 66.151.79.155.http > proxyserver.34232: P 23376:24313(937) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788710 IP 66.151.79.155.http > proxyserver.34232: P 24313:24315(2) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.788718 IP 66.151.79.155.http > proxyserver.34232: P 24315:24320(5) ack 653 win 64883 <nop,nop,timestamp 4801560 447503368>
> 16:54:49.992190 IP 66.151.79.155.http > proxyserver.34232: . 19272:20628(1356) ack 653 win 64883 <nop,nop,timestamp 4801562 447503581>
> 16:54:49.992211 IP 66.151.79.155.http > proxyserver.34232: . 20628:20640(12) ack 653 win 64883 <nop,nop,timestamp 4801562 447503581>
> 16:54:50.195357 IP 66.151.79.155.http > proxyserver.34232: F 24320:24320(0) ack 654 win 64883 <nop,nop,timestamp 4801564 447503785>
> 16:54:50.685028 IP 66.151.79.155.http > proxyserver.34232: F 24320:24320(0) ack 654 win 64883 <nop,nop,timestamp 4801570 447503785>
> 16:54:51.887986 IP 66.151.79.155.http > proxyserver.34232: F 24320:24320(0) ack 654 win 64883 <nop,nop,timestamp 4801582 447503785>
>
> Cheers, John
Received on Wed Oct 09 2013 - 06:26:51 MDT