The Web session and SSO session are differents things, session is create when you access a web application and this can live without autentication. SSO allows authentication to one resource to implicitly authorize access to other resources.
Then according documentation:
How SSO Works
If a resource is unprotected, a user is not challenged
to authenticate at all. If a user accesses a protected resource, the
user is required to authenticate.
Upon successful authentication, the
roles associated with the user are stored and used for authorization
of all other associated resources.
If the user logs out of an
application, or an application invalidates the session
programmatically, all persisted authorization data is removed, and the
process starts over.
A session timeout does not invalidate the SSO session if other sessions are still valid.
So if you want invalidate sso authtentication across cluster, you may call the method Request.logout()
, for example.
SSO Configuration Options:
maxEmptyLife:
Clustered SSO only. The maximum number of seconds an SSO
valve with no active sessions will be usable by a request, before
expiring. A positive value allows proper handling of shutdown of a
node if it is the only one with active sessions attached to the valve.
If maxEmptyLife is set to 0, the valve terminates at the same time as
the local session copies, but backup copies of the sessions, from
clustered applications, are available to other cluster nodes. Allowing
the valve to live beyond the life of its managed sessions gives the
user time to make another request which can then fail over to a
different node, where it activates the backup copy of the session.
Defaults to 1800 seconds (30 minutes).
Se also: Use Single Sign On (SSO) In A Web Application
Another thing is not possible configure a default session-timout
value in JBoss 7 (Like jboss 4, 5 and 6) so you'll have to configure this value in each application.
Eg. add in your web.xml:
<session-config>
<session-timeout>20</session-timeout>
</session-config>
I hope this help.