"mbroons" wrote:
Can i use this pattern to provide some kind of highly available cluster ?

Yes.

"mbroons" wrote:

I would have cluster A caches delegating to far cache A (inside the cluster A)
I would have cluster B caches delegating to far cache B (inside the cluster B)

Can i set up something like:

cluster A caches delegating to far cache A delegating to far cache B
cluster B caches delegating to far cache B delegating to far cache A

there is cyclic dependency there. What will happen exactly ?

Not a cyclic dependency, but far cache A and far cache B replicating to each other may cause issues. Why not just have something like:

Cluster A delegates to far cache A (FC-A)
Cluster B delegates to far cache B (FC-B)

FC-A and FC-B are in their own, separate cluster replicating state between themselves.

This way, you still have 2 separate clusters (A and B) using far cache backends (FC-A and FC-B), and FC-A and FC-B are fail-safe since they back up to each other, and also cluster A and B can see the state in each other via the far caches.