Hi Evgeny, thanks a lot for shared your experience, very interesting. I'd like to plug something magic that could avoid me configuring a filter, I started investigating about a possible use of AOP & HttpSession. If anyone is interested, I'll share my results when done. Best regards!!! Simo
http://people.apache.org/~simonetripodi/ On Tue, Feb 23, 2010 at 7:51 AM, Tsirkin Evgeny <tsir...@gmail.com> wrote: > Just in case somebody will google for a solution for "replacing session". > I have done this . > First of all ,why: > We have cluster of 2 machines . > Each have a separate db on it . > The machines are sharing information using nfs mounting fs. > Each machine runs it's own apache server ,(no apache balancer in front). > There IS a hardware load balancer in front of this but sometime it fails > to route already open sessions to same host. > So,we can't : > 1. share sessions using files ,because this would be same file for 2 tomcats > and because this would fail on nfs . > 2. we can't use tomcat cluster because there are cases when BOTH tomcat > would be shut down or restarted and session would be loosed. > 3. we can't use a db because there is no central db - each host has it's own > one. > 4. to complicate issue machines could be added/removed to the cluster. > > What we did - override session object using filter.On each request start it > would > read it's info from db (any configured one ,but preferring the local one) > On each request end it would write itself into ALL dbs that are configured > to be > used. > Although the obvious problem here is the writing to more then 1 db and > reading > from a db on each request ,this really works good thanks for mysql to be > so fast on simple read/write. > I have even implemented a simple lock mechanism for session . > What more - this solution is portable ,it worked for us on SunONE server > and now on tomcat. > Thanks > Evgeny > On Tue, Feb 16, 2010 at 9:54 PM, Simone Tripodi > <simone.trip...@gmail.com>wrote: > >> Hi Martin, >> very interesting, thanks for share it!!! I did, more or less, the same >> on a project for a customer, but it was strictly related to the >> application, your stuff looks much much better of mine and it is a >> reusable module. >> All the best, >> Simo >> >> http://people.apache.org/~simonetripodi/<http://people.apache.org/%7Esimonetripodi/> >> >> >> >> On Tue, Feb 16, 2010 at 6:02 PM, Martin Grotzke >> <martin.grot...@javakaffee.de> wrote: >> > Hi Jon, >> > >> > On Mon, 2010-02-15 at 11:55 -0600, Jon Brisbin wrote: >> >> I'm trying to figure out today how I can implement a Valve or something >> that can store a session to a backend DB and reload that session on another >> Tomcat instance similar to how the PersistentManager loads user's session >> after a restart. >> >> >> >> Would a Valve based on PersistentValve allow me to implement a >> cluster-like solution such that a user login causes a write to a central >> database and a load balanced request to another server would see that user >> without forcing another login? >> > You might have a look at the >> > http://code.google.com/p/memcached-session-manager/ which is a session >> > failover solution storing sessions in memcached. >> > >> > When the project was created I only thought of applications using sticky >> > sessions but it should also work with non-sticky sessions if sessions >> > are stored in memcached synchronously (sessionBackupAsync needs to be >> > set to false, see [1]). >> > >> > The memcached-session-manager basically is a session manager >> > implemention, the most interesting part is the >> > MemcachedBackupSessionManager ([2]) if you want to have a look at the >> > code. >> > >> > Cheers, >> > Martin >> > >> > >> > [1] >> http://code.google.com/p/memcached-session-manager/wiki/SetupAndConfiguration >> > [2] >> http://github.com/magro/memcached-session-manager/blob/master/core/src/main/java/de/javakaffee/web/msm/MemcachedBackupSessionManager.java >> > >> > >> > >> >> >> >> Jon Brisbin >> >> Portal Webmaster >> >> NPC International, Inc. >> >> >> >> >> >> >> >> On Feb 15, 2010, at 11:05 AM, Simone Tripodi wrote: >> >> >> >> > Hi all guys and very nice to meet the Tomcat community, >> >> > I've a web-application that needs to be replicated in more than one >> >> > Tomcat, and since it is HttpSession based, I need to enable the >> >> > session replication. >> >> > Even if I work with very good sysadmins that know how to do it, I'm >> >> > curious and would like to know if I could replace the HttpSession >> >> > implementation with a my own one, I'd like to integrate Hazelcast[1] >> >> > for data synchronization. >> >> > Thanks in advance, every suggestion will be very appreciated. >> >> > Simo >> >> > >> >> > [1] http://www.hazelcast.com/ >> >> > >> >> > http://people.apache.org/~simonetripodi/<http://people.apache.org/%7Esimonetripodi/> >> >> > >> >> > --------------------------------------------------------------------- >> >> > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org >> >> > For additional commands, e-mail: users-h...@tomcat.apache.org >> >> > >> >> >> >> >> >> --------------------------------------------------------------------- >> >> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org >> >> For additional commands, e-mail: users-h...@tomcat.apache.org >> >> >> > >> > -- >> > >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org >> For additional commands, e-mail: users-h...@tomcat.apache.org >> >> > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
