# rbd ls -p spoa
image01
image02

# rbd --image image01 -p spoa info
rbd image 'image01':
        size 300 GB in 76800 objects
        order 22 (4096 KB objects)
        block_name_prefix: rb.0.0
        parent:  (pool -1)
		

master ceph # rbd -c ceph.conf map image01 --pool spoa --name client.admin --secret key.admin


master ceph # rbd -c ceph.conf map image02 --pool spoa --name client.admin --secret key.admin

dmesg:
device label SAVAGE devid 1 transid 211 /dev/rbd1p1
btrfs: disk space caching is enabled
 rbd2: p1
rbd: rbd2: added with size 0x30000000000

Consultando partición de 3TB:
 # parted /dev/rbd2
GNU Parted 3.1
Using /dev/rbd2
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Model: Unknown (unknown)
Disk /dev/rbd2: 3299GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:

Number  Start   End     Size    File system  Name     Flags
 1      4194kB  3299GB  3299GB               logical
 
master ceph # mkfs.btrfs -L SERRANA /dev/rbd2p1

WARNING! - Btrfs Btrfs v0.19 IS EXPERIMENTAL
WARNING! - see http://btrfs.wiki.kernel.org before using

fs created label SERRANA on /dev/rbd2p1
        nodesize 4096 leafsize 4096 sectorsize 4096 size 2.00TB
Btrfs Btrfs v0.19


=============================================
Create partition aligned using parted

master spoa # parted /dev/rbd2 unit s p free
Model: Unknown (unknown)
Disk /dev/rbd2: 6442450944s
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:

Number  Start  End          Size         File system  Name  Flags
        34s    6442450910s  6442450877s  Free Space
		
Create partition aligned using parted
 # parted /dev/rbd2 p free
Model: Unknown (unknown)
Disk /dev/rbd2: 3299GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:

Number  Start   End     Size    File system  Name  Flags
        17.4kB  3299GB  3299GB  Free Space


master spoa # parted -a optimal /dev/rbd2 mkpart primary 0% 100%
Information: You may need to update /etc/fstab.		

master spoa # parted /dev/rbd2 p free
Model: Unknown (unknown)
Disk /dev/rbd2: 3299GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:

Number  Start   End     Size    File system  Name     Flags
        17.4kB  4194kB  4177kB  Free Space
 1      4194kB  3299GB  3299GB               primary
        3299GB  3299GB  4177kB  Free Space

# mkfs.btrfs -L SERRANA /dev/rbd2p1

WARNING! - Btrfs Btrfs v0.19 IS EXPERIMENTAL
WARNING! - see http://btrfs.wiki.kernel.org before using

fs created label SERRANA on /dev/rbd2p1
        nodesize 4096 leafsize 4096 sectorsize 4096 size 3.00TB
Btrfs Btrfs v0.19

=================================================
Create partition aligned using parted
http://unix.stackexchange.com/questions/38164/create-partition-aligned-using-parted
I'm partitioning a non-SSD hard disk with parted because I want a GPT partition table.

parted /dev/sda mklabel gpt
Now, I'm trying to create partitions correctly aligned so I use the next command to know where begins the first sector:

parted /dev/sda unit s p free

Disk /dev/sda: 488397168s
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number  Start  End         Size        File system  Name      Flags
        34s    488397134s  488397101s  Free Space
We can see that it starts in the sector 34 (it's by default when this partition table is used).

So, to create the first partition I tried:

parted /dev/sda mkpart primary 63s 127s
to align it in the sector 64 since it's multiple of 8 but it shows:

Warning: The resulting partition is not properly aligned for best performance.

The sector size logical and physical in my hard disk are both of 512 bytes:

cat /sys/block/sda/queue/physical_block_size
512

cat /sys/block/sda/queue/logical_block_size 
512
How to create partitions correctly aligned? What I'm doing wrong?