I need to make backups of my email archive on SuSe11. The archive consists of around 20 million files and is currently about 2 TB in size.
Is it a viable proposition to back this stuff up to a portable USB 3.0 drive. I assume there are drivers available in SuSE but I don't know
what the performance would be like. I have tried this on a fairly fast tape drive but it takes days to complete.

If this is not an option, what would you do?