I was wrong. It is not the remote server but Squid itself which is sending a FIN,ACK after ServerHelloDone. At 8 seconds, ServerKeyExchange, ServerHelloDone is received by Squid. The cipher suite looks like (ECDHE+RSA+SHA512 ,wireshark shows rsa_pkcs_sha512.) After about 60 more seconds (there is no activity on the wire during this period), Squid sends a FIN/ACK to the remote server effectively closing the connection. What debug_options should I be using for more relevant logging in cache.log ? 26,9 11,9 and 5,9 are not helping much. I am adding few loglines anyways. 2018/05/28 07:20:13.603 kid1| 5,4| AsyncCall.cc(26) AsyncCall: The AsyncCall clientLifetimeTimeout constructed, this=0x1c5e5f0 [call136782] 2018/05/28 07:20:13.603 kid1| 5,3| comm.cc(559) commSetConnTimeout: local=<Squid_IP>:3128 remote=<Client_IP>:64774 FD 13 flags=1 timeout 86400 2018/05/28 07:20:13.603 kid1| 11,5| HttpRequest.cc(460) detailError: current error details: 12/-2 2018/05/28 07:20:13.603 kid1| 11,2| Stream.cc(266) sendStartOfMessage: HTTP Client local=<Squid_IP>:3128 remote=<Client_IP>:64774 FD 13 flags=1 2018/05/28 07:20:13.603 kid1| 11,2| Stream.cc(267) sendStartOfMessage: HTTP Client REPLY: --------- HTTP/1.1 503 Service Unavailable Post splicing the webpage opens just fine. That website (www.pcmag.com) has over 750 DNS names added to SAN field. The RFC does not set an upper bound on the number of DNS names you can have in there. Regards, Sarfaraz -----Original Message----- From: Ahmad, Sarfaraz Sent: Thursday, May 17, 2018 4:18 PM To: 'squid-users@xxxxxxxxxxxxxxxxxxxxx' <squid-users@xxxxxxxxxxxxxxxxxxxxx> Cc: 'Marcus Kool' <marcus.kool@xxxxxxxxxxxxxxx> Subject: RE: TCP FIN,ACK after ServerHelloDone with pcmag.com Guys, Any thoughts ? Regards, Sarfaraz -----Original Message----- From: Ahmad, Sarfaraz Sent: Wednesday, May 16, 2018 10:36 AM To: 'Marcus Kool' <marcus.kool@xxxxxxxxxxxxxxx>; squid-users@xxxxxxxxxxxxxxxxxxxxx Subject: RE: TCP FIN,ACK after ServerHelloDone with pcmag.com I see a message similar to Marcus' in cache.log. 2018/05/16 00:20:10 kid1| ERROR: negotiating TLS on FD 77: error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed (1/-1/0) And I am running squid-4.0.24. Sarfaraz -----Original Message----- From: squid-users <squid-users-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Marcus Kool Sent: Wednesday, May 16, 2018 1:41 AM To: squid-users@xxxxxxxxxxxxxxxxxxxxx Subject: Re: TCP FIN,ACK after ServerHelloDone with pcmag.com The proxies that I used for the test have Squid 4.0.22 and Squid 4.0.23. Marcus On 15/05/18 15:40, Amos Jeffries wrote: > On 16/05/18 01:32, Marcus Kool wrote: >> pcmag.com also does not load here, although my config parameters are >> slightly different. >> The certificate is indeed huge... >> Do you have >> ERROR: negotiating TLS on FD NNN: error:14090086:SSL >> routines:ssl3_get_server_certificate:certificate verify failed >> (1/-1/0) or other errors in cache.log ? >> >> Marcus >> > > Are these Squid-4.0.24 ? There is a regression[1] in the cafile= > parameter handling in the latest release. > <https://bugs.squid-cache.org/show_bug.cgi?id=4831> > > Amos > _______________________________________________ > squid-users mailing list > squid-users@xxxxxxxxxxxxxxxxxxxxx > http://lists.squid-cache.org/listinfo/squid-users > _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users