POST problems and Apache hanging
Maybe this info can help in finding a solution to the POST and/or Apache hang problem. We are using a Java based client doing POSTs to a Apache/mod_ssl/Jserv server. The client uses bothe SSL session reuse and HTTP Keep-Alive (just like the Netscape browser). The problems seemed to be related to the use of Keep-Alive. At one time we experienced the following problems: * Apache would close the connection unexpectedly, often in the middle of the (n'th) output phase. (The close notify was sent, but the channel was closed too early). * Sometimes Apache processes would hang, not responding, but using all available cpu. I did not find out why Apache did this, but I found out how to avoid it. Our client had a bug causing it to send a few bytes more than the "Content-Length:" header said. Wen we fixed that, both Apache problems went away. -- Mats Josefsson ([EMAIL PROTECTED]) RSV DataService __ Apache Interface to SSLeay (mod_ssl) www.engelschall.com/sw/mod_ssl/ Official Support Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]
Re: POST problems and Apache hanging
On Wed, Mar 17, 1999, Mats Josefsson wrote: > Maybe this info can help in finding a solution to the POST and/or Apache > hang problem. > > We are using a Java based client doing POSTs to a Apache/mod_ssl/Jserv > server. The client uses bothe SSL session reuse and HTTP Keep-Alive > (just > like the Netscape browser). The problems seemed to be related to the use > of Keep-Alive. > > At one time we experienced the following problems: > > * Apache would close the connection unexpectedly, often in the middle > of the (n'th) output phase. (The close notify was sent, but the > channel > was closed too early). > > * Sometimes Apache processes would hang, not responding, but using all > available cpu. > > I did not find out why Apache did this, but I found out how to avoid it. > Our client had a bug causing it to send a few bytes more than the > "Content-Length:" header said. Wen we fixed that, both Apache problems > went away. That's _VERY_ interesting. This would explain the problems and the fact why I cannot find the reason although I've tried to trace it down more than once now with s_client. Hmmm seems like I've to check the request Netscape sends to the server byte by byte... thanks for the hint. Ralf S. Engelschall [EMAIL PROTECTED] www.engelschall.com __ Apache Interface to SSLeay (mod_ssl) www.engelschall.com/sw/mod_ssl/ Official Support Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]
Re: POST problems and Apache hanging
On Wed, Mar 17, 1999, Ralf S. Engelschall wrote: > On Wed, Mar 17, 1999, Mats Josefsson wrote: > > > Maybe this info can help in finding a solution to the POST and/or Apache > > hang problem. > > > > We are using a Java based client doing POSTs to a Apache/mod_ssl/Jserv > > server. The client uses bothe SSL session reuse and HTTP Keep-Alive > > (just > > like the Netscape browser). The problems seemed to be related to the use > > of Keep-Alive. > > > > At one time we experienced the following problems: > > > > * Apache would close the connection unexpectedly, often in the middle > > of the (n'th) output phase. (The close notify was sent, but the > > channel > > was closed too early). > > > > * Sometimes Apache processes would hang, not responding, but using all > > available cpu. > > > > I did not find out why Apache did this, but I found out how to avoid it. > > Our client had a bug causing it to send a few bytes more than the > > "Content-Length:" header said. Wen we fixed that, both Apache problems > > went away. > > That's _VERY_ interesting. This would explain the problems and the fact why I > cannot find the reason although I've tried to trace it down more than once now > with s_client. Hmmm seems like I've to check the request Netscape sends to > the server byte by byte... thanks for the hint. I've today again investigated a few hours and now finally found out at least where the problem stays: It's Apache's ``lingering close'' stuff in combination with kept-alive connections. After I've moved the connection close phase directly inside the lingering close code (and there after the socket flush but before the socket close) it now works fine for me. Both Axel's testtool CGI and the posted page1.html/page2.html example now works without any I/O errors or hangs. But I've still not understood why it doesn't work to wait for Netscape's SSL finish message. According to the SSL/TLS standard it seems to be ok for a server to only send the SSL finish message but not wait for the response of the client. But it's interesting that Netscape doesn't send it (instead mod_ssl would wait endless for it) while other clients do. I've now to cleanup my changes and a POST-bugfixed 2.2.5 version should be now possible. But 2.2.5 has to be released in combination with OpenSSL 0.9.2 (the reason I still cannot explain), so you've to wait a few more days. Ralf S. Engelschall [EMAIL PROTECTED] www.engelschall.com __ Apache Interface to SSLeay (mod_ssl) www.engelschall.com/sw/mod_ssl/ Official Support Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]
RE: POST problems and Apache hanging
I have the same problem using IE4.0 as well. So it is just not a Netscape issue. John > -Original Message- > From: Ralf S. Engelschall [mailto:[EMAIL PROTECTED]] > Sent: Wednesday, March 17, 1999 7:32 AM > To: [EMAIL PROTECTED] > Subject: Re: POST problems and Apache hanging > > > On Wed, Mar 17, 1999, Ralf S. Engelschall wrote: > > > On Wed, Mar 17, 1999, Mats Josefsson wrote: > > > > > Maybe this info can help in finding a solution to the > POST and/or Apache > > > hang problem. > > > > > > We are using a Java based client doing POSTs to a > Apache/mod_ssl/Jserv > > > server. The client uses bothe SSL session reuse and HTTP > Keep-Alive > > > (just > > > like the Netscape browser). The problems seemed to be > related to the use > > > of Keep-Alive. > > > > > > At one time we experienced the following problems: > > > > > > * Apache would close the connection unexpectedly, often > in the middle > > > of the (n'th) output phase. (The close notify was sent, but the > > > channel > > > was closed too early). > > > > > > * Sometimes Apache processes would hang, not responding, > but using all > > > available cpu. > > > > > > I did not find out why Apache did this, but I found out > how to avoid it. > > > Our client had a bug causing it to send a few bytes more than the > > > "Content-Length:" header said. Wen we fixed that, both > Apache problems > > > went away. > > > > That's _VERY_ interesting. This would explain the problems > and the fact why I > > cannot find the reason although I've tried to trace it down > more than once now > > with s_client. Hmmm seems like I've to check the > request Netscape sends to > > the server byte by byte... thanks for the hint. > > I've today again investigated a few hours and now finally > found out at least > where the problem stays: It's Apache's ``lingering close'' stuff in > combination with kept-alive connections. After I've moved the > connection close > phase directly inside the lingering close code (and there > after the socket > flush but before the socket close) it now works fine for me. > Both Axel's > testtool CGI and the posted page1.html/page2.html example now > works without > any I/O errors or hangs. > > But I've still not understood why it doesn't work to wait for > Netscape's SSL > finish message. According to the SSL/TLS standard it seems to > be ok for a > server to only send the SSL finish message but not wait for > the response of > the client. But it's interesting that Netscape doesn't send > it (instead > mod_ssl would wait endless for it) while other clients do. > > I've now to cleanup my changes and a POST-bugfixed 2.2.5 > version should be now > possible. But 2.2.5 has to be released in combination with > OpenSSL 0.9.2 (the > reason I still cannot explain), so you've to wait a few more days. > >Ralf S. Engelschall >[EMAIL PROTECTED] >www.engelschall.com > __ > Apache Interface to SSLeay (mod_ssl) www.engelschall.com/sw/mod_ssl/ > Official Support Mailing List [EMAIL PROTECTED] > Automated List Manager [EMAIL PROTECTED] > __ Apache Interface to SSLeay (mod_ssl) www.engelschall.com/sw/mod_ssl/ Official Support Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]