I was looking at a problem a coworker had. He was unable to create any tables in HBase.
As it turned out he had created a RegionObserver and loaded it at HBase start, which (as a test) just returned empty scanners from postOpenScanner(...). (In our case we will eventually have at least some clusters that will implement certain operators through RegionObservers for every table.) That led me to question: Should a RegionObserver be allowed to interfere with the system tables? Opinions? -- Lars
