I download metadata from http://geoportale.lamma.rete.toscana.it/MapStore/public/ based on this tutorial http://geoserver.geo-solutions.it/multidim/en/accessing_multidim/rtx/wind_arrows.html and extract it to a folder, so there is some .tiff files in it. then I opened my Geoserver 2.8.1 and on this path: Stores->add new Store-> ImageMosaic ( image mosaicking plugin) then choose the folder contains tiff files. then in the layer configuration, dimension tab, I should see that the time and elevation attributes are enabled as it is mentioned in the tutorial but they are not and The following message appears next to each of the respective enable checkboxes:
Cannot enable, no attribute of type Date found
Cannot enable, no attribute of type Number found
I already saw this question How to add time and elevation dimension attributes to Geoserver rasters? but that is not my case since I have not insert Geotiff Data into my Postgres or whatsoever. I spend two days on solving this and read a lot about it with googling the issue.