WildFly's use of JGroups

[nmoelholm]

Hey guys,

WildFly has several JGroups channels using different groups.

In a cluster.... is it possible that these channels, periodically, can have different views of the cluster (due to networking issues etc.) ? As an example: Given a cluster that is supposed to contain nodes A, B and C - can messaging have a different cluster view (Say: A,B) than hibernate (Say: A,B,C)? Or will they always be in sync ( see the same cluster members )?

Thank you,

Nicky

[pferraro]

In WF8, it is possible for the views of different channels to be different for very short periods of time, though this would be entirely due to timing issues - since the each channel stores its view in a distinct memory space, and failure detection tasks for each channel are not necessarily simultaneous.

However, the default configuration of WF9 multiplexes most clustering services over a single channel (except messaging, though that is planned).  Thus, in WF9, the channel view for each service will be identical.