(70007)The timeout specified has expired: proxy: error reading status line from remote server

[maurizio bella <lain80@xxxxxxxxx>]

Hi to all,
I have an httpd server with mod_proxy that forward any request to an 
another server.

the flow is: client --> requesto proxy https://miosito.it --> 
forward to server https://192.168.0.10:8443/

I'm reading this error in my httpd log in LogLevel debug (after some 
request).
After some request the proxy (or the backend server) don't response to any future requests.
How can find teh root cause?
many thanks for all suggest.

ssl_error.log:

Thu Apr 15 10:37:10 2010] [debug] ssl_engine_io.c(1821): OpenSSL: I/O error, 5 bytes expected to read on BIO#863acd0 [mem: 863b420]
[Thu Apr 15 10:37:10 2010] [info] [client 192.168.0.10] (70007)The timeout specified has expired: SSL input filter read failed.
[Thu Apr 15 10:37:10 2010] [error] [client 10.0.2.123] (70007)The timeout specified has expired: proxy: error reading status line from remote server 192.168.0.10, referer: https://miosito.it/cas-server-webapp-3.3.5/login?service=https%3A%2F%2Fmiosito.it%2FUAP%2Fj_spring_cas_security_check
[Thu Apr 15 10:37:10 2010] [debug] mod_proxy_http.c(1466): [client 10.0.2.123] proxy: NOT Closing connection to client although reading from backend server 192.168.0.10 failed., referer: https://miosito.it/cas-server-webapp-3.3.5/login?service=https%3A%2F%2Fmiosito.it%2FUAP%2Fj_spring_cas_security_check
[Thu Apr 15 10:37:10 2010] [error] [client 10.0.2.123] proxy: Error reading from remote server returned by /UAP/j_spring_cas_security_check, referer: https://miosito.it/cas-server-webapp-3.3.5/login?service=https%3A%2F%2Fmiosito.it%2FUAP%2Fj_spring_cas_security_check
[Thu Apr 15 10:37:10 2010] [debug] proxy_util.c(2062): proxy: HTTPS: has released connection for (192.168.0.10)
[Thu Apr 15 10:37:10 2010] [info] [client 10.0.2.123] Connection closed to child 7 with unclean shutdown (server miosito.it:443)


this is my system

# uname -a
Linux SRV01 2.6.18-128.el5 #1 SMP Wed Dec 17 11:42:39 EST 2008 i686 i686 i386 GNU/Linux
# rpm -qa | grep http
httpd-manual-2.2.3-31.el5_4.2
system-config-httpd-1.3.3.3-1.el5
jakarta-commons-httpclient-3.0-7jpp.1
httpd-2.2.3-31.el5_4.2
httpd-devel-2.2.3-31.el5_4.2
# rpm -qa | grep ssl
openssl-devel-0.9.8e-7.el5
mod_ssl-2.2.3-31.el5_4.2
docbook-style-dsssl-1.79-4.1
openssl-0.9.8e-7.el


and this my /etc/httpd/conf.d/ssl.conf


LoadModule ssl_module modules/mod_ssl.so
LoadFile   /usr/lib/libxml2.so
LoadModule proxy_html_module modules/mod_proxy_html.so
LoadModule xml2enc_module modules/mod_xml2enc.so

Listen 443
# Listen 444
AddType application/x-x509-ca-cert .crt
AddType application/x-pkcs7-crl    .crl
SSLPassPhraseDialog  builtin
SSLSessionCache         shmcb:/var/cache/mod_ssl/scache(512000)
SSLSessionCacheTimeout  300
SSLMutex default
SSLRandomSeed startup file:/dev/urandom  256
SSLRandomSeed connect builtin
SSLCryptoDevice builtin

NameVirtualHost miosito.it:443

#<VirtualHost *:443>
<VirtualHost miosito.it:443>
ServerName miosito.it
ErrorLog logs/ictservices_ssl_error_log
TransferLog logs/ictservices_ssl_access_log
#LogLevel debug

####ProxyRequests on
ProxyRequests off
ProxyPass / https://192.168.0.10:8443/
ProxyHTMLURLMap https://192.168.0.10:8443 /
<Location />
        ProxyPassReverse https://192.168.0.10:8443/
        ProxyHTMLEnable On
        ProxyHTMLURLMap  /      /
        RequestHeader    unset  Accept-Encoding
</Location>

SSLEngine on
SSLProxyEngine on
SSLProtocol all -SSLv2
SSLCipherSuite ALL:!ADH:!EXPORT:!SSLv2:RC4+RSA:+HIGH:+MEDIUM:+LOW
SSLCertificateFile /etc/httpd/cert/Global_Alternative.cer
SSLCertificateKeyFile /etc/httpd/cert/Global_Alternative.key
SSLCertificateChainFile /etc/httpd/cert/Global_CA.cer

<Files ~ "\.(cgi|shtml|phtml|php3?)$">
    SSLOptions +StdEnvVars
</Files>
<Directory "/var/www/cgi-bin">
    SSLOptions +StdEnvVars
</Directory>
SetEnvIf User-Agent ".*MSIE.*" \
         nokeepalive ssl-unclean-shutdown \
         downgrade-1.0 force-response-1.0
CustomLog logs/ssl_request_log \
          "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"
</VirtualHost>