Hi Bill, I've had a good look at the Ehcache/RMI replicated setup as documented on Confluence and think that may be our best bet in the long term. I'll have a chat with UNE and follow up to the list with any questions.
Thanks for all of the info. regards, Steve On 21/01/2012, at 2:14 AM, William G. Thompson, Jr. wrote: > On Fri, Jan 20, 2012 at 9:21 AM, Marvin Addison > <[email protected]> wrote: >>> This is caused by the service ticket being written to one node of the MySQL >>> cluster, >>> but then the other CAS node happens to get to do the service ticket >>> validation, >>> and it happens to use the other DB node, the ticket isn't found, because >>> database >>> replication hasn't been fast enough to bring the ticket over. >> >> I assume you're using traditional master-slave replication where no >> amount of tweaks will _guarantee_ replication on a timescale that >> would work in all cases. I believe you MUST use multi-master MySQL >> replication in order to make this work properly. Bill Thompson >> mentioned recently that he'd worked on such a setup and it worked >> admirably, so perhaps he can weigh in here with more information. >> > > The HA CAS setup we helped build for Lamar University is a multi-node > multi-site active/active architecture. The ticket registry is a > multi-master MySQL with synchronous replication. The solution > actually included two CAS clusters...one in each data center with some > fancy routing to make sure validate request ultimately land in the > right cluster. This solution is working well for Lamar. They > happened to be in hurricane alley and frequently use the alternate > data center. The decision to go with JPA and MySQL was mostly due to > Lamar's experience and expertise with MySQL. > > We've also helped University of New England (Australia) with a similar > HA CAS setup, but based on Ehcache (w/ simple RMI replication, not > Terracotta). They have been running in production since January 2011 > and report that their 2 node Ehcache setup has been running > "flawlessly". > > I'd recommend seriously considering your HA requirements and the > possibility of running a single node deployment, especially if you > running on virtualized hardware with inherent redundancy and > scalability. > > If you are convinced you need multi-node deployment, I'd try out Ehcache. > > Happy to go into further details with you. I should also point out > that Unicon of course provides consulting and support for CAS > deployments if you're looking for more direct help. > > Best, > Bill > > -- > You are currently subscribed to [email protected] as: > [email protected] > To unsubscribe, change settings or access archives, see > http://www.ja-sig.org/wiki/display/JSG/cas-user > -- You are currently subscribed to [email protected] as: [email protected] To unsubscribe, change settings or access archives, see http://www.ja-sig.org/wiki/display/JSG/cas-user
