tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Seth Ladd <>
Subject Re: Advice for Hosting Many Individual Webapps?
Date Thu, 18 Aug 2005 18:35:33 GMT
Mikolaj Rydzewski wrote:
> Seth Ladd wrote:
>> The frequency is so much that the uptime of all of our applications is 
>> affected as we continually take down Tomcat servers in production to 
>> deploy a new application (or new version of the application).  Because 
>> hot deploy does not work (the old favorite OOM error w/ too many 
>> redeploys), we bounce the Tomcat server for every redeploy.
> What about clustering? You could move users to one node of the cluster, 
> update apps in the second one, and then the opposite. Move users to the 
> second node, update the first one and finally allow users to work with 
> two (or more) nodes.

Yes, but then how to do you handle class evolution for objects in the 

For example, if I'm clustering two Tomcats, they are sharing Session 
state.  If I upgrade one node in the cluster, and possibly change a 
class definition of an object that gets stored in the session, I will 
now have two definitions of the same object (one for the old cluster 
node and one for the new cluster node).  I think there will be 
serialVersionUID issues there.

Advice on how to handle that?


To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message