A simple exemple to make Replication for RBD.

Based on this post from scuttlemonkey : http://ceph.com/dev-notes/incremental-snapshots-with-rbd/, here is a sample script to synchronize rbd image on a remote cluster (eg for backups). In the example below, the sync is made to an "archive" pool on the same …

The aim is showing that it is possible to create a low-cost storage, efficient and scalable, using opensource solutions. In the example below, I am using Ceph for scalability and reliability, combined with EnhanceIO to ensure very good performance.

Architecture

The idea was to create a storage with two parts …

Create a disk with an insane size can be fun, but a little hard to remove.

Here's a little trick (use with caution!) to remove a too big image for rm rbd (if image is not initialized, or not fully).

Image format 1 :

$ rbd info rbdbigsize
rbd image 'rbdbigsize':
    size …

An exemple for migrating journal from file on the default location to a dedicated partition on /dev/sde1.

$ apt-get install hdparm

### Stop osd
$ service ceph stop osd.0

### Flush Journal
$ ceph-osd --flush-journal -i 0

### Create symlink to partition
$ rm /var/lib/ceph/osd/ceph-0/journal
$ ln -s /dev/sde1 /var …

6 months since my last post... Firefly is released. http://ceph.com/releases/v0-80-firefly-released/

Ceph Major Release