Thoughts on Openstack London 2014



I attended Openstack London this week in the beautiful surroundings of Bishopsgate 155, right in the centre of the ‘city’.

A few thoughts:


Although I have not deployed Ceph yet it is something I am very interested in.  I love the idea of disrupted feature rich storage on commodity hardware.  John Spray from Inktank did an awesome job of taking us through an introduction to Ceph outlining why distributed storage is hard to do and how Ceph attacks those challenges.  He then talked about the most recent features in the latest release.  I particularily like Cache tiering:

  • Cache tiering: support for creating ‘cache pools’ that store hot, recently accessed objects with automatic demotion of colder data to a base tier. Typically the cache pool is backed by faster storage devices like SSDs.

This is great; have the reads on SSDs and the replicas on slow mechanical disks.  I can see so many use cases for that

  • Primary affinity: Ceph now has the ability to skew selection of OSDs as the “primary” copy, which allows the read workload to be cheaply skewed away from parts of the cluster without migrating any data.

   This is also very cool from an operational standpoint.

Finally John demo’d calamari – the previously enterprise only web interface and management tool for Ceph.  I am sure this will be very useful in production deploys.  Kudos to Redhat for opensourcing this as part of the Inktank aqusition.


Canonical were sponsors and presenters at the event.  Mark Shuttleworth had a somewhat shaky time doing his demo’s but overall it was pretty interesting.  I already knew about cloud init etc so nothing massively new there.  My takeaway was Juju which I had also dismissed as Canonicals take on config management. I know realise that it’s much more of an Orchestration tool, like Mcollective.  Will try and carve out some time to test some Juju deploys later this week.


Networking is obviously a core component of Openstack and a few talks covered aspects, with Mark McClain doing the deepest dive.  Of all the components in Openstack, Neutron and networking is the one I think is the most challenging.  The loadbalanacing on demand was not really covered but was interested to hear it’s based on Haproxy but does not support SSL yet.





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