DevOpsDays Chicago

October 12, 2014August 31, 2015 Josh Reichardt 16 Comments

As a first timer to this event, and first timer to any devopsdays event I’d like to write up a quick summary of the event and write about a few of the key takeaways that I got from the event. For anybody that isn’t familiar, the devopsdays events are basically 2 day events spread out through the year at different locations around the world. You can find more information on their site here:

http://devopsdays.org/

The nice thing about the devopsdays events is that they are small enough that they are very affordable ($100) if you register early. One unique thing about the events is their format, which I really liked. Basically the first half of the day is split up in to talks given by various leaders in the industry followed by “Ignite” talks which are very brief but informative talks on a certain subject, followed by “open spaces”, which are pretty much open group discussions about topics suggested by event participants. I spoke to a number of individuals that enjoyed the open spaces, even though they didn’t like all of the subjects covered in the talks. So I thought there was a very nice balance to the format of the conference and how everything was laid out.

I noticed that a number of the talks focused on broad cultural topics as well as a few technical subjects as well. Even if you don’t like the format or topics you will more than likely at least learn a few things from speakers or participants that will help you moving forward in your career. Obviously you will get more out of a conference if you are more involved so go out of your way to introduce yourself and try to talk to as many people as you can. The hallway tracks are really good to introduce yourself and to meet people.

So much to learn

One thing that really stood out to me was how different the composition and background of attendees really was. I met people from gigantic organizations all the way down to small startup companies and basically everything in between. The balance and mixture of attendees was really cool to see and it was great to get some different perspective on different topics.

Another fact that really stood out to me was that the topics covered were really well balanced, although some may disagree. I thought heading in to the conference that most of the talks were going to be super technical in nature but it turned out a lot these talks revolved more around the concepts and ideas that sort of drive the DevOps movement rather than just tools that are associated with DevOps.

One massive takeaway that I got from the conference was that DevOps is really just a buzzword. The definition that I Have of DevOps at my organization may be totally different than somebody else’s definition at a different company. What is important is that even though there will be differences in implementation at different scales, a lot of the underlying concepts and ideas will be similar and can be used to drive change and improve processes as well as efficiency.

DevOps is really not just about a specific tool or set of tools you may use to get something accomplished, it is more complicated than that. DevOps is about solving a problem or set of problems first and foremost, the tooling to do these tasks is secondary. Before this event I had these two distinguishing traits of DevOps backwards, I thought I could drive change with tools, but now I understand that it is much more important to drive the change of culture first and then to retool you environment once you have the buy in to do so.

Talk to people

One of the more underrated aspects of this conference (and any conference for that matter) is the amount of knowledge you can pick up from the hallway track. The hallway track is basically just a way to talk to people that you may or may not have met yet who are doing interesting work or have solved problems that you are trying to solve. I ran in to a few people who were working on some interesting challenges *cough* docker *cough* in the hallway track and I really got a chance for the first time to see what others are doing with Docker which I thought was really cool.

Open spaces were another nice way to get people to intermingle. The open spaces allowed people working on similar issues to put heads together to discuss specific topics that attendees either found interesting or were actively working on. A lot of good discussion occurred in these open spaces and a good amount of knowledge was spread around.

Conclusion

DevOps is not one thing. It is not a set of tools but rather a shift in thinking and therefore involves various cultural aspects, which can get very complicated. I think in the years to come, as DevOps evolves, a lot more of these aspects will become much more clear and will hopefully make it easier people to get involved in embracing the changes that come along with the DevOps mentality.

Current thought leaders in the DevOps space (many of them in attendance at devopsdays Chichago) are doing a great job of moving the discussion forward and there are some awesome discussions at the devopsdays events. Podcasts like Arrested DevOps, The Ship Show and DevOps Cafe are definitely creating a lot of good discussion around the subject as well. Judging from my observations from the event, it seems there is still a lot of work to be done before DevOps becomes more common and mainstream.

Patching CVE-6271 (shellshock) with Chef

September 26, 2014August 31, 2015 Josh Reichardt 2 Comments

If you haven’t heard the news yet, a recently disclosed vulnerability has been released that exploits environmental variables in bash. This has some far reaching implications because bash is so widespread and runs on many different types of devices, for example network gear, routers, switches, firewalls, etc. If that doesn’t scare you then you probably don’t need to finish reading this article. For more information you can check out this article that helped to break the story.

I have been seeing a lot “OMG the world is on fire, patch patch patch!” posts and sentiment surrounding this recently disclosed vulnerability, but basically have not seen anybody taking the time to explain how to patch and fix this issue. It is not a difficult fix but it might not be obvious to the more casual user or those who do not have a sysadmin or security background.

Debian/Ubuntu:

Use the following commands to search through your installed packages for the correct package release. You can check the Ubuntu USN for versions.

dpkg -l | grep '^ii' or
dpkg-query --show bash

If you are on Ubuntu 12.04 you will need update to the following version:

bash    4.2-2ubuntu2.3

If you are on Ubuntu 13.10, and have this package (or below), you are vulnerable. Update to 14.04!

 bash 4.2-5ubuntu3

If you are on Ubuntu 14.04, be sure to update to the most recently patched patch.

bash 4.3-7ubuntu1.3

Luckily, the update process is pretty straight forward.

apt-get update
apt-get --only-upgrade install bash

If you have the luxury of managing your environment with some sort of automation or configuration management tool (get this in place if you don’t have it already!) then this process can be managed quite efficiently.

It is easy to check if a server that is being managed by Chef has the vulnerability by using knife search:

knife search node 'bash_shellshock_vulnerable:true'

From here you could createa a recipe to patch the servers or fix each one by hand. Another cool trick is that you can blast out the update to Debian based servers with the following command:

knife ssh 'platform_family:debian' 'sudo apt-get update; sudo apt-get install -y bash'; knife ssh 'platform_family:redhat' 'sudo yum -y install bash'

This will iterate over every server in your Chef server environment that is in the Debain family (including Ubuntu) or RHEL family (including CentOS) and update the server packages so that the latest patched bash version gets pulled down and then gets updated to the latest version.

You may need to tweak the syntax a little, -x to override the ssh user and -i to feed an identity file. This is so much faster than manually installing the update on all your servers or even fiddling around with a tool like Fabric, which is still better than nothing.

One caveat to note: If you are not on an LTS version of Ubuntu, you will need to upgrade your server(s) first to an LTS, either 12.04 or 14.04 to qualify for this patch. Ubuntu 13.10 went out of support in August which was about a month ago as per the time of this writing so you will want to get your OS up date.

One more thing: The early patches to address this vulnerability did not entirely fix the issue, so make sure that you have the correct patch installed. If you patched right away there is a good chance you may still be vulnerable, so simply rerun your knife ssh command to reapply the newest patch, now that the dust is beginning to settle.

Outside of this vulnerability, it is a good idea to get your OS on an Ubuntu LTS version anyway to continue receiving critical updates for software as well as security patches for a longer duration than the normal, 6 month release cycle of the server distribution.

Analyzing cloud costs

September 24, 2014August 31, 2015 Josh Reichardt 19 Comments

Knowing about and controlling the costs of a cloud environment is not only good to know how to do as an admin/engineer, it also greatly helps others inside your organization. Knowing your environment and cost overhead also makes you (or your team) look better when you can pinpoint bottlenecks, as well as anomalies in your environment, and create solutions to mitigating costs or otherwise track cloud resource utilization. Plus, it can even get you some extra credit.

So with this in mind, I’d like to talk about a few strategies and tools I have been experimenting with to help road map and accurately model different costs and utilization for different workloads spread out accross an AWS environment.

ICE

The first tool I’d like to mention is ICE and is probably my favorite tool. It is a tool developed by Netflix and analyzes costs across your AWS infrastructure. It gives you nice graphs and advanced breakdowns of prices, including spot pricing vs on demand and many other permutations across your AWS infrastructure.

This is the best explanation I can find, pulled right from their github page:

The ability to trend usage patterns on a global scale, yet decompose them down to a region, availability zone, or service team provides incredible flexibility. Ice allows us to quantify our AWS footprint and to make educated decisions regarding reservation purchases and reallocation of resources.

It has a nice interface and some slick filtering, so breaking things down on a region by region level becomes easy, which is otherwise not the case for the other tools. This tool is also great for spotting trends and anomalies in your environment which can sometimes go undetected if not viewed in the correct context.

The downside is the overhead associated with getting this up and running bu there is a Chef cookbook that will pretty much do the installation for you, if you are comfortable with Chef. You will need to override some attributes but otherwise it is pretty straight forward. If you need assistance let me know and I’d be glad to walk you through getting it set up.

AWS Calculator

This is a handy tool to help ballpark and model various costs for AWS services. One disappointing discovery of this tool is that it doesn’t help model spot instance prices.

This is great for mocking out what the TCO of a server or group of servers might look like. It is also good for getting a general feel for what different server costs will be for a certain number of months and/or years.

Be sure to check this out to help stay current on the most recent news because AWS moves quickly with seemingly constant updates and have been dropping prices steadily over the past 3 years. Especially with the increased competition from Microsoft (Azure) and Google (Google Cloud), AWS seems to be constantly slashing prices and adding new improvement and features to their product.

AWS Billing and Cost Management

This one is pretty self explanatory. It is built right in to AWS and as such, it can be a very powerful tool that can easily be overlooked. It offers a variety of detailed information about costs and billing. It offers some nice graphs and charts for trend spotting and can be exported for analysis, which is also nice (even though I haven’t got that far yet).

The major downside (in my opinion) is that you can’t get the granular price breakdowns that are available with a tool like ICE. For example, there isn’t an easy way to find a price comparison breakdown for cost per region or other more detailed information.

Trusted Advisor

This tool is great and is free for basic usage. This offering from AWS is really nice for helping to find and optimize settings according to a number of good practice recommendations created by Amazon. Not only does it give you some really nice price breakdowns but it also reports things like security and performance which can be equally useful. Use this often to tighten up areas of your infrastructure and to optimize costs.

One down for this one is that to unlock all of the features and functionality you need to upgrade to the enterprise version which is obviously more expensive.

AWS ELK Billing

I just found out about this one but it looks like it might be a very nice solution, leveraging the Logstash + Kibana stack. I have written a post about getting started with the ELK stack so it shouldn’t be difficult at all to begin playing around with this solution if you are interested.

If you get this tool up and working I would love to hear about it.

Cost saving tips

I have compiled a list of simple yet powerful tips to help control costs in AWS. Ideally a combination of all of these tips would be used to help control costs.

Upgrade server and service instance generations as often as possible for automatic improved performance and reduced price. For example gen 1 to gen 3, m1.xxx -> m3.xxx.
Try to size servers correctly by keeping them busy. Servers that are running but aren’t doing anything are essentially wasting money. Either run them according to time of day or bump up the amount of utilization per box, either by downsizing the server or upping the workload.
On that note, size servers correctly according to workload. For example a workload that demands CPU cylces should not be deployed as a memory optimized server.
Adopt on demand instances and utilize them early on. On demand prices are significantly lower than standard prices. Just be careful because your on demand instances can disappear.
In the same ilk of on demand instances, use reserved instances. These instance types can significantly reduce prices, and have the advantage that they won’t disappear so long running servers and services benefit from this type of cost control.
Set up granular billing as early as possible. Create and optimize alerts based on expected usage for tighter control of costs. It’s better to start off knowing and controlling environment costs sooner than later.
Delete unused EBS volumes. Servers and volumes can come and go, but often times EBS volumes can become orphaned and essentially no good. Therefore it is a good idea to clean up unused EBS volumes whenever you can. Of course this process can and should be automated.

Conclusion

Managing cost and optimizing your cloud infrastructure really could be considered its own discipline in some regards. Environments can become complex quite quickly with instances, services and resources spinning up and down as well as dynamically growing up and down to accommodate workloads as well as ever evolving environments can lead to what some call “Cloud Sprawl”.

The combination of the tools and cost savings tips mentioned above can be a real lifesaver when you are looking to squeeze out the most bang for your buck out of your cloud environment. It can also lead to a much more solid understanding of all the moving pieces in your environment and can help determine exactly is going on at any given time, which is especially useful for DevOps admins and engineers.

If you have any other cool tips or tips for controlling AWS costs or other cloud environment costs let me know, I’ll be sure to add them here!

Test Kitchen Tricks

September 2, 2014August 31, 2015 Josh Reichardt 27 Comments

I have been working a lot with Chef and Test kitchen lately and thus have learned a few interesting tricks when running tests with these tools. Test Kitchen is one of my favorite tools when working with Chef configuration management because it is very easy to use and has a number of powerful features that make testing things in Chef simple and easy.

Test Kitchen itself sits on top of Vagrant and Virtualbox by default so to get started with the most basic usage example of Test Kitchen you will need to have Vagrant installed along with a few other items.

Vagrant (your distribution)
Virtualbox (again with your distribution)
Ruby 1.9 or higher + ruby gems

Then to install Test Kitchen.

gem install test-kitchen

That’s pretty much it. The official docs have some pretty detailed usage and in fact I have learned many of the tricks that I will be writing about today from the docs.

Once you are comfortable with Test Kitchen you can begin leveraging some of the more powerful features, which is what the remainder of this post will cover. There is a great talk given by the creator of test kitchen at this year’s Chefconf by the creator of Test Kitchen about some of the lessons learned and cool things that you can do with the tool. If you haven’t already seen it, it is worth a watch.

Anyway, let’s get started.

1) Fuzzy matching

This one is great for the lazy people out there. It basically allows you match a certain unique part of a command instead of typing out an entire command. So for example, you can just type in a partial name for a command to return the desired full command. Since Test Kitchen uses regular expression matching, this can be a very powerful feature.

2) Custom drivers

One reason that Test Kitchen is so flexible is because it can leverage many different plugins and drivers. And, since it is open source, if there is functionality missing from a driver you can simply write your own. Currently there is an awesome list of drivers available for Test Kitchen to use, and a wide variety of options available to hopefully suit most testing scenarios.

Of course, there are others as well. These just happen to be the drivers that I have tried and can verify. There is even support for alternate configuration management tool testing, which can be handy for those that are not using Chef specifically. For example there is a salt driver available.

3) .kitchen.local.yml

This is a nice handy little bit that is often overlooked but allows a nice amount of control by overriding the default .kitchen.yml configuration file with specific options. So for example, if you are using the ec2 driver in your configuration but need to test locally with Vagrant you can simply drop a .kitchen.local.yml on your dev machine and override the driver (and any other settings you might need to change). I have created the following .kitchen.local.yml for testing on a local Vagrant box using 32 bit Ubuntu to highlight the override capabilities of Test Kitchen.

driver: 
 name: vagrant 
 
platforms: 
 - name: ubuntu-1310-i386 
 - name: ubuntu-1404-i386

4) Kitchen diagnose

An awesome tool for diagnosing issues with Test Kitchen. Running the diagnose will give you lots of juicy info about what your test machines are doing (or should be doing) and a ton of configuration information about them. Basically, if something is misbehaving this is the first place you should look for clues.

If you want to blast info and settings for all your configurations, just run the following,

kitchen diagnose

5) Concurrency

If you have a large number of systems that need to have tests run on them then running your Test Kitchen tests in parallel is a great way to speed up your total testing time. Turning on concurrency is pretty straight forward, just add the “-c” flag and the number of instances to run on (the default is 9999).

kitchen converge -c 5

6) Verbose logging

This one can be helpful if your kitchen run is failing with no real clues or helpful information provided by the diagnose command. It seems obvious but getting this one to work gave me some trouble initially. To turn on verbosity simply add the debug flag to your test kitchen command.

So for example, if you want to converge a node with verbosity turned on, you would use this command.

kitchen converge -l debug

I recommend taking a look at some or all of these tricks to help improve your integration testing with Test Kitchen. Of course as I stated, all of this is pretty well documented. Even if you are already familiar with this tool, sometimes it just helps to have a refresher to remind you of a great tool and to jar your memory. Let me know if you have any other handy tricks and I will be sure to post them here.

Transitioning from bash to zsh

August 16, 2014August 31, 2015 Josh Reichardt 1 Comment

I have know about zsh for a long time now but have never really had a compelling reason to switch my default shell from bash until just recently, I have been hearing more and more people talking about how powerful and awesome zsh is. So I thought I might as well take the dive and get started since that’s what all the cool kids seem to be doing these days. At first I thought that changing my shell was going to be a PITA with all the customizations and idiosyncrasies that I have grown accustomed to using bash but I didn’t find that to be the case at all when switching to zsh.

First and foremost, I used a tool called oh-my-zsh to help with the transition. If you haven’t heard about it yet, oh-my-zsh aims to be a sort of framework for zsh. This project is a nice clean way to get started with zsh because it give you a nice set of defaults out of the the box without having to do much configuration or tweaking and I found that many of my little tricks and shortcuts were already baked in to to oh-my-zsh, along with a ton of other settings and customizations that I did not have using bash.

From their github page:

oh-my-zsh is an open source, community-driven framework for managing your ZSH configuration. It comes bundled with a ton of helpful functions, helpers, plugins, themes, and few things that make you shout…

Here are just a few of the improvement that zsh/oh-my-zsh offer:

Improved tab completion
persistent history across all shells
Easy to use plugin system
Easy to use theme system
Autocorrect

The most obvious difference that I have noticed is the improved, out of the box tab completion, which I think should be enough on its own to convince you! On top of that, most of my tricks and customizations were already turned on with oh-my-zsh. Another nice touch is that themes and plugins come along as part of the package, which is really nice for easing the transition.

So after spending an afternoon with zsh I am convinced that it is the way to go (at least for my own workfolw). Of course there are always caveats and hiccups along the way as I’ve learned there are with pretty much everything.

Tuning up tmux

Out of the box, my tmux config uses the default shell, which happens to be bash. So I needed to modify my ~/.tmux.conf to reflect the switch over the zsh. It is a pretty straight forward change but is something that you will need to make note of kif you use tmux and are transitioning in to using zsh.

set-option -g default-shell /usr/bin/zsh

I am using Ubuntu 14.04, so my zsh is installed to /usr/bin/zsh. The other thing that you will need to do is make sure you kill any stale tmux processes after updating to zsh. I found one running in the background that was blocking me from using the new coonfig.

Goodies

There is a nice command cheat sheet for zsh. Take some time to learn these shortcuts and aliases, they are great time savers and are very usefull.

oh-my-zsh comes bundled up with a large number of goodies. At the time of this writing there were 135 plugins as well as a variety of themes. You can check the plugins wiki page for descriptions for the various plugins. To turn on a specific plugin you will need to add it to your ~/.zshrc config file. Find the following line in your config.

plugins=(git)

and add plugins separated by spaces

plugins (git vagrant chef)

You will need to reload the config for the changes to be picked up.

source ~/.zshrc

Most themes are hosted on the wiki, but there is also a web site dedicated to displaying the various themes, which is really cool. It does a much better job of showing differences between various themes. You can check it out here. Themes function in a similar way to plugins. If you want to change your theme, edit your ~/.zshrc file and select the desired them.

ZSH_THEME="clean"

You will need to reload your config for this option as well.

source ~/.zshrc

Conclusion

If you haven’t already made the switch to zsh I recommend that you at least experiment and play around with it before you make any final decisions. You may be set in your ways and happy with bash or any other shell that you are used to but for me, all the awesomeness changed my opinion and decide to reevaluate my biases. If you’re worried about making the switchin, using oh-my-zsh makes the transition so painless there is practically no reason not to try it out.

This post is really just the tip of the iceberg for the capabilities of this shell, I just wanted to expose readers to all of its glory. Zsh offers so much more power and customization than I have covered in this post and is an amazing productivity tool with little learning overhead.

Let me know if you have any awesome zsh tips or tweaks that folks should know about.