I have similar problem when I started the clustering (it is still not working with a lot of other problems, not sure the clustering was properly tested), but regrading to the data source issue, I ended up deleting the resources and recreated then again and enabled to all targets. I guess if the resource already existed but adding it to the new target some how does not really worked even the admin console showing them enabled. You can also use asadmin to reset the resource, but using the admin console is easier.
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