• 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…]

  • Virtual Bare Metal Provisioning Lab with MAAS on KVM

    MAAS on KVMMAAS (Metal As A Service) has caught my eye over the past couple of years.  It has tremendous system deployment value.  Imagine the cloud automation methods in use today, and apply that to racks full of traditional server hardware.  That’s where MAAS is maturing.  But then, perhaps, through some sort of rabbit hole, that bare metal provisioning concept could be turned inside out to expose further power and value back in the virtualization realm from whence it came.  Yes.  It can.  I predict that it will thrive in both.

    If you haven’t seen it in action, it’s definitely worth taking for a spin.  But what if you don’t have a bunch of servers, or a pile of old computer hardware to throw at building a test lab?  Enter, my general system deployment rule #1:  “Virtualize By Default.”   In other words, show me a good reason *not* to virtualize in scenario X.  Granted:  I’ll admit that there are some good reasons, but IMHO, there are few.

    Moving along then… as I was executing some ISO testing for the upcoming Ubuntu Server 14.04 (Trusty Tahr) release, I decided to capture pieces of that work.  The YouTube playlist below is the net product of that little journey.  [Read More…]

  • Linux server remote admin and performance monitoring tools

    byobu on beisner.com

    This is a short video which demonstrates a “tabbed SSH” tool, persistent remote session features and network performance monitoring utilities that I like to use when doing remote Linux server administration.  Using the upcoming Ubuntu Server 14.04 Trusty Tahr LTS, I touch on byobu, htop, nethogs, nload and iptraf while stepping through some of the basic and practical uses of each.

    For more tales, stories and practical info about linux, virtualization, cloud, continuous integration, devops, Ubuntu Server, JuJu, MAAS, OpenStack and the such, watch for more on the SYSOPS FABLES channel on YouTube.  There is also a playlist which is specific to general Linux server command line administration, where I will post future guides.

    More to come – enjoy!