Hi,
On Thu, Mar 23, 2017 at 4:20 PM, Wayne W <[email protected]>
wrote:
> Hi Martin,
>
> that was a typo on my part. I've been doing a lot more testing before I
> replied to make sure things are as I say. This is what I am observing:
>
>
> - I have a 2 node tomcat cluster setup with apache balancing between
> them locally on my machine.
> - Testing with a very simple Wicket app I can see the replication is
> working fine when shutting down either instance.
> - Testing with our very heavy weight wicket app it sometimes work and
> sometimes does not.
>
> Now the last point above I have narrowed down to our homepage. If I am not
> on the homepage the replication seems to work ok. However if I am on the
> homepage I always get a ComponentNotFoundException when failing over to the
> other instance.
> The homepage has an AbstractDefaultAjaxBehavior which is called once the
> page is rendered, this in turn adds to the the page a DataView containing a
> lot of content and links. The user needs to be logged in before they see
> the homepage, so the session is already setup.
>
> I don't know what it is about this page that breaks the replication. Is
> there anything around the ajax part that could do this? Any pointers would
> be most welcome as it will be a long long task to break that page down and
> do rounds and rounds of cluster testing
>
Let's try something!
In you Ajax callback method do something like:
getSession().setAttribute("someKey", UUID.randomUUID().toString())
Does this trigger replication ?
>
> many thanks
>
>
>
>
> On Wed, Mar 22, 2017 at 12:34 PM, Martin Grigorov <[email protected]>
> wrote:
>
> > Hi,
> >
> > "I can stop one of the instances and I'm not logged in"
> > This statement says that you don't really have a properly configured
> > failover.
> > If those two Tomcat instances are in a cluster then the http sessions
> > should be replicated and you should stay logged in no matter which one is
> > serving the request.
> > Wicket will store the used stateful page at the disks for all Tomcats in
> > the cluster, if it the replication is actually working!
> >
> >
> > On Wed, Mar 22, 2017 at 1:02 PM, Wayne W <[email protected]>
> > wrote:
> >
> > > Hi,
> > >
> > > We have 2 instances of Tomcat running with Apache sitting in front
> > > balancing between the Tomcat instances. I have session replication
> setup
> > > which seems to work for basic bookmarkable links on the pages. I can
> stop
> > > one of the instances and I'm not logged in as it failover to the other
> > > instance.
> > >
> > > However for normal Link<?> and ajax links etc I get
> > > ComponentNotFoundException thrown as the new instance cannot find it
> in
> > > the session it seems.
> > >
> > > Clearly I'm not understanding how wicket manages the page state or I've
> > > configured something wrong.
> > >
> > > Does wicket support full session failover ?
> > >
> > > Many thanks
> > >
> >
>
