• Welcome

    Welcome!  Here you will find posts about things that I find interesting:  OpenStack, Open Source, Ubuntu Server, Linux, Cloud Computing, and other miscellaneous, sometimes random thoughts. 

    As with any of my content, this is not official documentation, and it may not apply to your your specific environment.  The opinions expressed here are my own, not the formal stance of any other party.  Take care, always test in a non-production environment, and remember to Read The Full Manual.

     I hope you enjoy.  Feel free to find me or contact me for discussion.

    Best to you!

  • OpenStack, Outer Space & Left Eyes

    I just realized that I have a conflict of abbreviation.  Common interpretation of “OS” in the industry is generally operating system, and sometimes open source.  To those outside the cloud industry, perhaps one-size, outer-space, or even oculus sinister (the left eye).

    Not to minimize the importance of an operating system, a left eye or outer space, but for the sake of saying:  I hereby propose that the old-skool meanings of OS are obsolete.  Used in a naked context, or without clarifying qualifiers, the OS acronym shall now equate:  OpenStack.  Granted, I could be biased.  Just a silly thought this morning, there you have it.

  • Offline Instance Migration with Nova Compute

    In managing or testing an OpenStack private cloud environment, it may be periodically necessary to offload nova compute workloads to perform planned server maintenance. Live migration is often preferred and is generally the best option, as it requires zero instance downtime. Motivations for choosing to do an offline migration over a live migration can certainly vary, depending on any number of variables such as shared storage configuration, hardware condition, hypervisor flavor, or perhaps the nova compute, qemu or KVM versions that are in play. Whatever the reason, here is a simple example of an offline migration.

    This environment is OpenStack Icehouse 2014.1, Juju-deployed onto MAAS-managed Ubuntu Server 14.04 LTS Trusty Tahr nodes. Storage back-end is ceph RBD, but other shared storage options should do as well. It’s all open source, and it’s all free as in … freedom to learn, or freedom to buy support if or as needed. By the way, I just love that about open source. Ok back on track, here goes:

    The short version:

    # For offline migration, the instance should be
    # in a STOPPED / shutoff state!  Use nova stop for
    # non-graceful shutdown of the vm, if you must.
    
    # Get the instance ID
    nova list --all-tenants | grep my-instance
    
    # Confirm the current state and hypervisor node
    nova show ab90cc7a-7022-4157-b32a-11c49b7701cc
    
    # Migrate the instance, nova scheduler decides where
    nova migrate ab90cc7a-7022-4157-b32a-11c49b7701cc
    
    # Watch & wait
    watch nova migration-list
    
    # Seal the deal
    nova resize-confirm ab90cc7a-7022-4157-b32a-11c49b7701cc
    
    # Confirm the goods
    nova show ab90cc7a-7022-4157-b32a-11c49b7701cc
    
    # Fire it up
    nova start ab90cc7a-7022-4157-b32a-11c49b7701cc

    [Read More…]

  • OpenStack One-Liners

    One-line bash commands for managing, deploying and testing OpenStack and related components, hypervisors and containers.  Some simple and obvious, some cool and questionable, hopefully all useful.  Check back on this post, I’ll likely add more.

    #1 – Watch Nova Compute for Non-Active Instances on Openstack

    Outputs total instance count and non-active instances. Useful for keeping an eye on potential problem VMs in a PAUSED, ERROR, SHUTOFF or other non-active state.

    Command:
    watch --interval=1 'nova list --all-tenants | wc -l && nova list --all-tenants | grep -v "ACTIVE"'

    nova-tenant-list

    [Read More…]

  • Red Hat testing the OpenStack waters

    I’ve been following OpenStack’s maturity pretty closely over the past year.  Since the late 1990’s, I’ve taken note that as goes Red Hat, so goes the herd when it comes to enterprise Linux solutions.  Of course, in many cases, that may very well be “I like what you’ve got going, watch me do it better.”  That is also is not to minimize the impressive impact of Canonical, HP, IBM, Mirantis and Rackspace.  This is merely an observation that when Red Hat throws their support and weight at a project, things tend to change.

    As a relative late-comer to the OpenStack Foundation (platinum member since 2012), Red Hat is contributing $500K per year and a sizable chunk in terms of software engineering labor.  One must assume that it intends to monetize these efforts with a Red Hat OpenStack offering some day soon.  If so, what does that mean for RHEL pet projects oVirt and Aeolus?  And RHEV?  Who knows.  Their continued sponsorship of those projects raises my eyebrow a bit, that they might just be slightly over-hedged and confused.

    Meanwhile, Canonical seems to be quietly dominating this developing space with Ubuntu Server.  It will be interesting to watch as Canonical and Red Hat cloud platform offerings mature.  I’ll be looking for the OpenStack.  May the most clever hat or non-hat win.