State Management and Clustering (IdP)

[Paul Hethmon]

On 11/11/12 5:19 PM, "Cantor, Scott" <cantor.2 at osu.edu> wrote:

>Speaking personally, I'm deeply skeptical of most clustering/replication
>technologies. I'm not a fan of asynchronous "best effort" replication, and
>most other types aren't very robust. I would be more comfortable with that
>for something like logout, that has no hope of being reliable anyway, than
>for mainline features like attribute queries.

To add a bit to this, even though I wrote that extension with Infinispan
for the current version, I've abandoned it for my own use. In my data
center, it worked pretty well, but in a few customer hosted sites, I had
problems even getting it working. Tuning the network parameters seems a
big challenge.

I ended up writing another storage plug-in that persisted sessions to a
database, with heavy support for not throwing errors if the database is
down. So I have a full local copy of anything that starts on that server,
send it to the database for persistence and to move the session to another
server. If a server doesn't have a local copy of the session, it will ask
the database for it. If it can't get it from the database, then that user
will simply have to login again.

It works, its simple. There are times when the effort to get something
cool like Infinispan working is just not worth it.

Paul