Planet Ceph

Aggregated news from external sources

  • July 30, 2013
    Convert RBD to Format V2

    Simple Import / Export

    Don’t forget to stop IO before sync and unmap rbd before rename.

    $ rbd export rbd/myrbd – | rbd import –image-format 2 – rbd/myrbd_v2
    $ rbd mv rbd/myrbd rbd/myrbd_old
    $ rbd mv rbd/myrbd_v2 rbd/myrbd

    Check :

  • July 30, 2013
    Remove Snapshot Before Rbd

    $ rbd rm rbd/myrbd
    2013-07-30 14:10:13.341184 7f9e11922760 -1 librbd: image has snapshots – not removing
    Removing image: 0% complete…failed.
    rbd: image has snapshots – these must be deleted with ‘rbd snap purge’ before the …

  • July 30, 2013
    Using Ceph-deploy

    Install the ceph cluster

    On each node :

    create a user “ceph” and configure sudo for nopassword :

    $ useradd -d /home/ceph -m ceph
    $ passwd ceph
    $ echo “ceph ALL = (root) NOPASSWD:ALL” | sudo tee /etc/sudoers.d/ceph
    $ chmod 0440 /e…

  • July 26, 2013
    Ceph: update Cephx Keys

    It’s not really clear from the command line

    Generate a dummy key for the exercise

    $ ceph auth get-or-create client.dummy mon 'allow r' osd 'allow rwx pool=dummy'

    key = AQAPiu1RCMb4CxAAmP7rrufwZP…

  • July 11, 2013
    Inktank Presenting on Ceph at FinTech Demo Day!

    It’s been quite a year for Inktank and the Ceph community. We are super excited to announce another major milestone for Inktank – our participation in the third annual FinTech Innovation Lab in New York City. The goal of the Lab – established in 2010 by Accenture and the Partnership Fund for New York City […]

  • June 23, 2013
    What I think about CephFS in OpenStack

    I recently had some really interesting questions that led to some nice discussions.
    Since I received the same question twice, I thought it might be good to share the matter with the community.

    The question was pretty simple and obvioulsy the context…

  • June 11, 2013
    Ceph RBD Online Resize

    Extend rbd drive with libvirt and XFS

    First, resize the device on the physical host.

    Get the current size :

    $ qemu-img info -f rbd "rbd:rbd/myrbd"

    Be careful, you must specify a bigger size, shrink a volume is destructive for the FS.

    $ qemu-img resize -f rbd "rbd:rbd/myrbd" 600G

    List device define for myVM :

    $ virsh domblklist myVM

    Resize libvirt blockdevice :

    $ virsh blockresize --domain myVM --path vdb --size 600G
    $ rbd info rbd/myrb

    Extend xfs on guest :

    $ xfs_growfs /mnt/rbd/myrbd

    Extend rbd with kernel module

    You need at least kernel 3.10 on ceph client to support resizing.
    For previous version look at

    Get current size :

    $ rbd info rbd/myrbd

    Just do :

    $ rbd resize rbd/myrbd --size 600000
    $ xfs_growfs /mnt/rbd/myrbd

    Also, since cuttlefish you can’t shrink a bloc device without specify additional option (–allow-shrink)

  • June 3, 2013
    Ceph integration in OpenStack: Grizzly update and roadmap for Havana

    What a perfect picture, a Cephalopod smoking a cigar! Updates!
    The OpenStack developer summit was great and obviously one of the most exciting session was the one about the Ceph integration with OpenStack.
    I had the great pleasure to attend this sess…

  • May 16, 2013
    ViPR: A software-defined storage mullet?

    Almost every few weeks, new storage products are announced by competitors and I generally avoid commenting on them. But EMC’s ViPR announcement contains attempts to perform both marketing and technical sleight of hand around software-defined storage that potentially do much to slow down the inevitable change that is coming to the storage market. While EMC […]

  • May 13, 2013
    Deploy a Ceph MDS server

    How-to quickly deploy a MDS server.

    Assuming that /var/lib/ceph/mds/mds is the mds data point.

    Edit ceph.conf and add a MDS section like so:

    mds data = /var/lib/ceph/mds/mds.$id
    keyring = /var/lib/ceph/mds/mds.$id/mds.$id.keyring


  • May 11, 2013
    What a Year 1!

    Back in January I posted about how Inktank’s momentum was accelerating. Well, to say this trend is continuing would be a gross understatement. The Inktank team continues to execute at a blinding pace and the world keeps on noticing. For example: •    The Community and Marketing (we are hiring) teams killed it at the OpenStack Summit. There […]

  • May 7, 2013
    Use existing RBD images and put it into Glance

    The title of the article is not that explicit, actually I had trouble to find a proper one. Thus let me clarify a bit. Here is the context I was wondering if Glance was capable of converting images within its store. The quick answer is no, but I thin…