Here's the dashboard:
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And here's the aggregate tab:
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show aggregate agrees with the information displayed on the aggregate tab. However there are a couple of strange things:
1) I deleted a volume that had 8TB of data... and only 2TB of available space showed up.
2) When I querey the volumes for physical space used, it is not equal to what I am seeing with show aggregate, it is equal to what I'm seeing with the dashboard.