Women in Technology

Article:		Clustering and Load Balancing in Tomcat 5, Part 2
Subject:		Fail over utility, Load balancing with URL redirecting
Date:		2004-08-22 12:37:36
From:		srinip
Response to: Fail over utility, Load balancing with URL redirecting
Hi, Thanks for the feedback on Clustering and Load Balancing article. Can you e-mail me the error message you are getting when using ServerUtil class. I have the configuration working on my home PC and am curious to see what kind of error message the load balance is throwing in your configuration. Also, regarding URL redirecting it should work by redirecting the Http request to the available cluster member (this is a simple forward to the new URL). This should work with any URL (internal server or external). Let me know what's the server configuration you are using in your web application. -Srini

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• Fail over utility, Load balancing with URL redirecting
  2004-08-23 17:02:36  yogesh_prajapati [View]
  
  
  As such your server util class works fine but it always starts and stops MCastService as many times as no of rules configured in rules.xml. This process is repeated for ever single incoming request. I am not sure if this is a good approach to be adopted. During start/stop of this temporary McastService there are warnings generated on other tomcat instancess running "clusterapp", I have sent the stack trace to you via email.
  
  About Redirection: I had a look into Tomcat BalanceFilter code it uses response.sendRedirect(..) method. There should be provision for more than just redirect. (I know this is something beyond the scope of what you have done) As I understand from the real application needs , this should not be (and can not be) a simple forward to new URL because of two reasons:
  
  1. Size limitation on URL rewriting. What if your request has a number of parameters size of which spans over beyond the limit of data your URL could carry. I am talking about simple URL size limit in HTTP GET Vs HTTP POST secenarios.
  
  2. Redirecting to local internal server (where actual Tomcat server running) changes the URL on client web browser (in this case to local internal address as hardcoded in rules.xml) and hence not acceptable. I think there should exactly the same mechanism between Tomcat Worker and actual Tomcat Server as it has been between Apache and Tomcat to for request forwarding transparently.
  
  ideas.....?????