Does the Identity Manager suite support running in fully active-active mode across 2 data centers? Has anyone does this successfully?
Assuming it's Oracle RAC, it's supported as a Identity Manager user store and runtime store, seeing https://support.ca.com/phpdocs/7/5655/5655_r126_SP6_PSM.pdf
When talking about running identitymanager as active active across datacenters, it is usually always assumed that you are talking about putting identitymanager into a cluster configuration.
The clustering is always supported by the application server, and the only application server configuration that I have seen that cannot be used across datacenters is Jboss in multicast.
This is not a limitation of identitymanager, or even jboss, this is a limitation of network router configuration on the multicast protocol used in the configuration. When Jboss is configured to use Mulicast, it sends out mass network messages on the MULTIcast protocol to all devices on a network to see if they are a jboss cluster member. Network Admins hate this as it causes pack storms so out of the box almost all network routers have multicast disabled.
So, IF this was not disabled on the network routers, then all cluster configurations would be supported in active active clustermode. It is just safer for us supporting identitymanager to say that is you are crossing datacenters, please use a more robust appserver with a proper support contract with that app server vender, not jboss communities.
Long winded answer, but that is why.
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