On Mon, 17 Dec 2001, Tom Drake wrote:
> Date: Mon, 17 Dec 2001 07:47:23 -0800
> From: Tom Drake <[EMAIL PROTECTED]>
> Reply-To: Tomcat Users List <[EMAIL PROTECTED]>,
> Tom Drake <[EMAIL PROTECTED]>
> To: Tomcat Users List <[EMAIL PROTECTED]>
> Subject: Re: Configuring Multiple Tomcat JVMs with Apache - Load Balancing
>
> When my work is done, Session Affinity will not be required in order to
> acheive load balancing. However, we should still want to use session
> affinity in our load balancing solution(s) for the simple reason that
> it will perform better.
>
As you look at (re)designing this feature, *please* keep in mind that the
servlet spec (both 2.2 and 2.3) requires a certain amount of session
affinity in any conforming container -- in particular, all of the
simultaneous requests to a particular session *must* be served by the same
JVM. A distributed server can migrate a session if it wants to, but only
"in between" requests.
By this definition, the session affinity provided in Tomcat 3.x via AJPv13
conforms to the requirements (it doesn't support migration, but that's not
required).
> However, the session affinity between Apache and Tomcat 3 locks
> a user (based on her JSESSIONID) to a single Tomcat instance. Once
> the distributed session management solution is in place, Apache should
> 'prefer' NOT 'force' tomcat instance routing. This gives us a real fail-over
> story. Administrators will be able to bring down Tomcat instances without
> blowing away 'logged in' users.
>
> Tom
>
Craig
--
To unsubscribe: <mailto:[EMAIL PROTECTED]>
For additional commands: <mailto:[EMAIL PROTECTED]>
Troubles with the list: <mailto:[EMAIL PROTECTED]>
