Hi, we encounter some strange errors with our apache (v2.2) fronting 4 tomcat (v5.5) server. We are loadbalancing with sticky sessions to our tomcats. Everything runs fine beside the fact that 0.1% of all requests get a 503 http status code. The rate raises under load, but it is at least 0.1% (way too much!!) and occurs even at the early morning hours. The request is not logged on the tomcat side (no exceptions, no access.log), only on apache access.log with 503 and error log as stated below. 1. This is from our apache log file: [Wed Mar 25 07:08:44 2009] [error] [client 74.6.22.94] (70014)End of file found: proxy: error reading status line from remote server tc1 [Wed Mar 25 07:08:44 2009] [error] [client 74.6.22.94] proxy: Error reading from remote server returned by /site.html 2. This is from our apache config (prefork engine) KeepAlive Off ServerLimit 650 ListenBackLog 50 StartServers 50 MinSpareServers 100 MaxSpareServers 200 MaxClients 300 MaxRequestsPerChild 10000 ProxyRequests Off <Proxy balancer://tomcatcluster> BalancerMember http://tc1:80 max=100 route=tc1 BalancerMember http://tc2:80 max=100 route=tc2 BalancerMember http://tc3:80 max=100 route=tc3 BalancerMember http://tc4:80 max=100 route=tc4 Order Deny,Allow Allow from all </Proxy> ProxyPass / balancer://tomcatcluster/ stickysession=JSESSIONID|jsessionid ProxyPassReverse / http://tc1/ ProxyPassReverse / http://tc2/ ProxyPassReverse / http://tc3/ ProxyPassReverse / http://tc4/ ProxyPreserveHost On 3. This is our connector from our tomcat configuration <Connector port="80" URIEncoding="UTF-8" maxHttpHeaderSize="8192" maxThreads="200" minSpareThreads="100" maxSpareThreads="200" enableLookups="false" acceptCount="25" connectionTimeout="10000" disableUploadTimeout="true" maxKeepAliveRequests="100" compression="on" compressionMinSize="2048" noCompressionUserAgents="gozilla, traviata" compressableMimeType="text/html,text/xml,text/css" /> I tried to investigate this problem but wasn't even able to reproduce it on my test engine. Googling it, i found some other people having this problem but no solution. As far as i understand from my investigations "BalancerMember http://tc1:80 max=100" does not make sense on "prefork". max should be 1 with prefork model. But i think this is not the reason. if max=100 is not effective, there "could" be situations where MaxClients of 300 all go to one tomcat because of session affinity. But this is rather theoretical. Maybe i can't use keepalive on the tomcat side. But it seems to work. But honestly: i am clueless. Do you have any hints why i do encounter these connection errors? Or does anybody has a running configuration with apache2.2, mod_proxy_balancer and tomcat 5.5. where these problems does not occur? kind regards Peter --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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