On 03/06/15 17:37, Chris Murphy wrote:
I actually have an additional problem. I built my system on a hard drive, then purchased a SSD, both 1TB. The first thing I would like to do is move my system to the SSD. But the SSDs have limited lifespan so I was hoping to keep an image of the SSD on the existing hard drive. btrfs is supposed to optimize blocking for SSD drives, so I would like it to make the optimized partitions, which I assume will be different than on the rotating media.
Backup the volume first. Then you can:
You can unmount the HHD, remount it with -o ssd, and then: btrfs device add <ssddev> <mp> btrfs device delete <hdddev> <mp>
This will migrate extents to the ssd using the ssd optimization. The one thing that's different about the state of the SSD in this case, is metadata profile is DUP since that's the HDD default. If you want metadata profile set to single, which is the SSD default, you can do a balance btrfs balance start -mconvert=single -f <mp>
-f is required to force this because you are reducing redundancy.
would have thought somebody would have made an app like rsync to do this before putting btrfs is full use. In the medical community, for instance, one is required by law to keep off site backups in case of fire etc.
I think you're conflating different things. Exactly reproducing a Btrfs volume onto another volume while retaining the deduplication of snapshots isn't possible yet, and poses some challenges. You can still rsync the current tree(s) excluding snapshots. There couldn't possibly be a law that requires you to use the same filesystem for the backup, as for the source. Certainly you could rsync the current tree to e.g. XFS using rsync and meet backup requirements.
As for future work in this area:
https://btrfs.wiki.kernel.org/index.php/Project_ideas#Rsync_integration https://btrfs.wiki.kernel.org/index.php/Project_ideas#Take_recursive_snapsho...
You are correct about the legals. It was just my lazy way to get everything saved in one operation. Patient data would not be on the btrfs portion of the system. I was just hoping that there was a global solution, perhaps such as you suggested for migrating between the disks in my system. And I need to look into dirvish with the btrfs patches described in the link you posted. Thanks, Don -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org