On 28/04/2015 17:24, Neil Bothwick wrote: > On Tue, 28 Apr 2015 17:01:49 +0200, Alan McKinnon wrote: > >> When you use only LVM for this and nothing else, you have a high risk of >> losing everything if one disk fails. Why? Because LVM decides itself >> which extent it will put data on. Maybe a whole file is on one disk, >> maybe it's spread across two, because the software is designed so that >> you don't have to be concerned with that. The only thing that LVM does >> is expand your storage space as a single volume and make it easier to >> shuffle things around without having to backup/repartition/restore. > > An alternative is to create a new volume group on the new disk and mounts > PVs at various points in your home directory. That way you get the extra > space and much of the flexibility without the risk of a failure on a > single drive taking out data on both. However, if you are concerned about > data loss, you should be using RAID t a minimum, preferably with an error > detecting filesystem.
I've used that scheme myself in the past. You do get the increased space but you don't get much in the way of flexibility. And it get COMPLICATED really quickly. To get around the situation of one drive almost full and the other having lots of space, folks often use symlinked directories, which you forget about and no-one else can figure out what you did... It all smacks of the old saw: For any non-trivial problem, there is always at least one solution that is simple, elegant, and wrong. -- Alan McKinnon [email protected]
