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I'm running QGIS 2.6 on OSGeo-Live 8.4 Virtual Machine based on Lubuntu 14.04.
I've set up a GRASS (GRASS GIS 7) environment in QGIS, and I have a merged .tif file of LiDAR images open in QGIS, so I want to use the grass tools to read the LiDAR image. Both the "grass tools" menu option and symbol are not highlighted and I can't select them (but some Grass tools are available such as add Grass raster/vector layer). What am I missing? How can I access the Grass tools?