I'm using a fairly vanilla Ubuntu 10.04 server installation, and I'm experimenting with BTRFS.
How can I create a BTRFS RAID1 mount?
I've got two (2) 1Gig drives that I popped in the server and after running the following commands, it appears I've got a 2 Gig partition, not 1 Gig as I would expect.
$ sudo mkfs.btrfs -m raid1 -d raid1 /dev/sdb /dev/sdc WARNING! - Btrfs Btrfs v0.19 IS EXPERIMENTAL WARNING! - see http://btrfs.wiki.kernel.org before using failed to open /dev/btrfs-control skipping device registration adding device /dev/sdc id 2 failed to open /dev/btrfs-control skipping device registration fs created label (null) on /dev/sdb nodesize 4096 leafsize 4096 sectorsize 4096 size 1.82TB Btrfs Btrfs v0.19
Okay ... errors. But if I plow ahead, I can mount this, and when I do a
df, I see 2 Gigs free:
$ mkdir btrfs && sudo mount -t btrfs /dev/sdc $(pwd)/btrfs $ cd btrfs && df . -h Filesystem Size Used Avail Use% Mounted on /dev/sdc 1.9T 28K 1.9T 1% /home/jamie/btrfs
I'd expected to see only one.