Using listpermission mine on any of the nodes gives me the nodeA (first node) address only. However during setup, I set "anyone-can-mine" to true and also observed from looking at the blocks that all nodes are actually participating in the mining. The listpermission mine result is confusing.
P.S I have noticed similar confusions with the other permissions. Although this is not really a problem for me, but I am wondering if there is an explanation or am I missing the meaning of the permissions?