Article View: borland.public.cppbuilder.internet.socket
Article #2574Strange event using TServerSocket / TClientSocket
From: Alex Liu
Date: Tue, 28 Mar 2006 11:02
Date: Tue, 28 Mar 2006 11:02
46 lines
3055 bytes
3055 bytes
I am not sure if this is the right place for my question. Pls help/forgive me if i post it wrong. i have two server side applications, A and B, which use TServerSocket in blocking mode for communicating with clients. The server socket threads will perform both read and write operations. In my case the two servers and just sending heartbeat only. A client application connects to the 2 servers via Intranet (in office). This case all are working fine. Now the whole system is put to a higher explosure level by setting up of VPN. Home users first connects to Internet, then connects to the office by NetScreen (a H/W + S/W 3rd party package) which provides SSL encryption over the connection. After VPN has established the user is able to run my client application. However, server A, under this situation, will crash (just simply disappeared) while B still works fine. The time of crash after client has connected varies from serveral minutes to an hour. I added logs in A and found that there seems to be a disconnection (maybe because of Internet connection) so the client should be disconnected from A before crash. And, AFTER 20 SECONDS, another disconnection event occur which has no identity. This is the last log i got before crash. The log i applied is simply adding log message to log file recording incoming IP and socket handle which is recorded in dtor() of the socket thread. The result shows that the IP is empty and no socket handle. This means no ctor() is called beforehand. I dont know why an extra disconnection is taking place. sample log: 15:00:00.000 disconnect IP=123.123.123.1 socket handle=222 .... // other log 15:00:20.213 disconnect IP= socket handle= // ??? an extra info but i dont know whether it helps: My user found that when another Intranet user is connecting and turned the machine (MS Window) to sleep mode, the crash will take place otherwise there is no problem. Technically speaking I think there should be no relation but it really seems so. I am not sure if i provide enough information or ...... I dont know. Please kindly advice.
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X-Google-Thread: 11508e,acb2b1ff7e8b813c,start X-Google-Attributes: gid11508e,public X-Google-Language: ENGLISH,ASCII-7-bit From: "Alex Liu" <alexliu@hket.com> Newsgroups: borland.public.cppbuilder.internet.socket Subject: Strange event using TServerSocket / TClientSocket Date: Tue, 28 Mar 2006 19:02:49 +0800 Lines: 48 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-RFC2646: Format=Flowed; Original NNTP-Posting-Host: 218.189.206.62 Message-ID: <4429183e$1@newsgroups.borland.com> X-Trace: newsgroups.borland.com 1143543870 218.189.206.62 (28 Mar 2006 03:04:30 -0700) Path: arc1-ca.pugleaf.net!g2news1.google.com!news3.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!newsfeed00.sul.t-online.de!newsfeed01.sul.t-online.de!t-online.de!newsgroups.borland.com!not-for-mail