Not really covered, no. 

I'm thinking maybe convoy-monitor (which is currently the only user of this lib) should just keep track of the ZK state and restart itself if it loses contact. The drawback with this is of course that it might not come up for a while if ZK goes down. OTOH, it won't be able to do all its stuff anyway since it can't read/write markers etc to ZK. And the only thing that would really be lost is host metrics data..?