Proxy Error 502 The proxy server received an invalid response from an upstream server

Question

We are building a mass mailing sending application in Java  Mail is being send by third party SMTP  After sending 400-500 mails tomcat6 service get stopped  Below is the error      Proxy Error        The proxy server received an invalid response from an upstream server  The proxy server could not handle the request GET    lin Campaignn jsp          Reason  Error reading from remote server   Additionally  a 502 Bad Gateway error was encountered while trying to use an ErrorDocument to handle the request   Apache Server at msizzler com Port 80  But when we are sending from localhost I did not received any error  It send all the mails  Please help me to sort it out this problem

User · Answer

Add this into your httpd conf file  Timeout 2400 ProxyTimeout 2400 ProxyBadHeader Ignore

User · Answer

The HTTP 502  Bad Gateway  response is generated when Apache web server does not receive a valid HTTP response from the upstream server  which in this case is your Tomcat web application   Some reasons why this might happen    Tomcat may have crashed The web application did not respond in time and the request from Apache timed out The Tomcat threads are timing out A network device is blocking the request  perhaps as some sort of connection timeout or DoS attack prevention system   If the problem is related to timeout settings  you may be able to resolve it by investigating the following    ProxyTimeout directive of Apache s mod proxy Connector config of Apache Tomcat Your network device s manual

User · Answer

The java application takes too long to respond maybe due start-up jvm being cold  thus you get the proxy error    Proxy Error  The proxy server received an invalid response from an upstream server   The proxy server could not handle the request GET  lin Campaignn jsp    As Albert Maclang said amending the http timeout configuration may fix the issue    I suspect the java application throws a 500  error thus the apache gateway error too  You should look in the logs

User · Answer

I had this issue once  It turned out to be database query issue  After re-create tables and index it has been fixed   Although it says proxy error  when you look at server log  it shows execute query timeout  This is what I had before and how I solved it

[java] Proxy Error 502 : The proxy server received an invalid response from an upstream server

Examples related to java

Examples related to email

Examples related to proxy

Examples related to tomcat6