Hi Frank-

I believe the release included (un-tested) support for distributed EhCache. Our 
tests indicated problems under even a low amount of traffic. Therefore, Scott 
was working with others in supporting other implementations:

Scott Battaglia wrote:
> We're currently testing a JBossCacheTicketRegistry that performs much 
> better than the EhCache ticket registry.  Its scheduled to be included 
> in 3.1


> Another possibility could be the jdbc based ticket registry on CASM. 
> Any opinions ?

We've also considered a backend db (oracle here) to support clustered CAS 
servers. The two obvious solutions seem:

1. distributed caches
2. database backend

I like distributed caches since it is generally light-weight though I'm not 
sure how it will scale with the number of servers/traffic increasing. Assuming 
you have a DB backend available/scalable, this seems to support a large number 
of CAS server front-ends though the DB will be hit pretty hard.

In the end, we are trying to do two things: 

a. insuring availability of the CAS session - if one CAS server goes down or a 
request goes to another CAS server, the ticket is available for validating

b. insuring scalability of the CAS service - adding additional CAS servers to 
increase capacity


Note that item "b" plays into item "a", i.e., adding a second (or third) CAS 
server requires the ticket be accessible (through a distributed registry or db).


There is a third option that we considered. It could be possible to generate 
tickets with a suffix identifier, then configure HTTP request routing to the 
CAS servers (through a content switch or apache) to inspect the Request URIs 
and/or cookies for this identifier and route to the correct CAS server. This 
insures scalability of the CAS service (item b), though it does not insure 
availability of the CAS session (item a). This seemed more difficult to 
configure/maintain in production, so we stopped looking into this.

Anyway, Scott should be back from holiday in a few days, so he might be able to 
shed more light on this topic.

Dan



Frank Taffelt wrote:
> Hi,
> 
> in the release notes for the CAS Server 3.0.5 is the new distributed Ticket 
> Registry feature mentioned. Could someone elaborate more on this topic, 
> mainly how to configure and use it ?
> 
> I want to use CAS now in a loadbalanced enviroment and i'm trying to figure 
> out how to realize this. Maybe the distributed ticketregistry could help 
> here. Another possibility could be the jdbc based ticket registry on CASM. 
> Any opinions ?
> 
> Thanks,
> Frank 
>
_______________________________________________
Yale CAS mailing list
[email protected]
http://tp.its.yale.edu/mailman/listinfo/cas

Reply via email to