I am following this example - http://linfiniti.com/2009/09/image-mosaicking-with-gdal/
I have 6TB of aerial imagery in 6 folders 1TB each and each folder has many subdirectories including the geotiffs. I am using gdal_translate to compress the data first. Then I use gdalbuildvrt to create the mosaics, and finally I build the pyramids/overviews for the mosaics using gdaladdo.
My target is to use geoserver to serve all the aerial data connected together. My concern is that a subdirectory may be 100GB which takes quite a while to process (either compress or building pyramids). This is why I did not use gdal on all 6TB at once and preferred handling them in different directories. Thus, my question is whether or not I will be able to use something like gdal_merge to connect all the pyramitised mosaics together to a bigger mosaic and serve it using geoserver or similar OS software.
Apologies for the huge post! Thanks in advance for any hints or tips.