In order to prepare for my CCIE R&S recert, and in an attempt to save trees, I bought the e-book (Kindle edition) of CCIE Routing and Switching Certification Guide, 4th Edition from Amazon.com. The print edition costs at least $20 more than the Kindle edition. However, after a few weeks of reading it on my first generation Kindle, I returned it to Amazon and bought the print edition instead. Here are the reasons why:
Monthly Archives: January 2013
Handling Kernel Updates with Open vSwitch
Last month I wrote how I built Open vSwitch 1.4.0 package on Ubuntu 12.04. Immediately afterwards I left my lab and when I returned to it, nearly a month later, I ran an apt-get upgrade out of habit. Consequently, the kernel got upgraded from 3.2.0-34 to 3.2.0-36 and I ran into the following error when starting the OVS service:
root@pakdude-02:~# uname -a
Linux pakdude-02 3.2.0-36-generic #57-Ubuntu SMP Tue Jan 8 21:44:52 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
root@pakdude-02:~# service openvswitch-switch start
FATAL: Module openvswitch_mod not found.
* Inserting openvswitch module
Module has probably not been built for this kernel.
For instructions, read
/usr/share/doc/openvswitch-datapath-source/README.Debian
FATAL: Module openvswitch_mod not found.
* Inserting openvswitch module
root@pakdude-02:~#
It turns out that this was because the kernel modules also needed to be updated. The following command did the trick:
root@pakdude-02:~# module-assistant auto-install openvswitch-datapath
I could have simply typed the following instead with the same consequences.
root@pakdude-02:~# m-a a-i openvswitch-datapath
As per the documentation, module-assistant aims to facilitate the process of building kernel modules from source. In other words, this needs to be run each time the kernel is upgraded.
Book Review – OpenStack Cloud Computing Cookbook
In December 2012, I participated in a contest on Scott Lowe’s blog and won a copy of Kevin Jackson’s OpenStack Cloud Computing Cookbook. I’ve been reading it to progress my OpenStack lab and have a few thoughts on it.
The most important thing to keep in mind about this book is that it is not about the design philosophy or goals of OpenStack. If you are looking for an OpenStack 101 book, this is not the one. It is very simply, a cookbook with precise recipes or tasks to set up and manage OpenStack cloud environments, and doesn’t pretend to be anything other than that. Hence, it is very difficult for it to be a meaningful and long-lasting book. This is unlikely to be on my bookshelves in a year or two. OpenStack has been evolving very rapidly and at the time the book was published, in September 2012, OpenStack came out with a new release – Folsom. The book was developed on the Essex platform, which was around April 2012. Folsom is a major release as it contains the Quantum networking component. Consequently, the book only covers Nova Networking (Chapter 10), which supports Flat networking, Flat networking with DHCP, and VLAN Manager. With, Quantum, users are presented a backend platform from which they can leverage plugins to pick network services from many vendors. Similarly, there is no mention of Cinder, the full-blown component that covers block storage. Instead, the book only talks about Nova Volumes (Chapter 8) for block storage support.
The OpenStack components present in Essex receive coverage in the following chapters:
- Nova (Compute) – Chapters 1 (Starting) and 2 (Administering)
- Keystone (Identity) – Chapter 3
- Swift (Storage) – Chapters 4 (Installing), 5 (Using), and 6 (Administering)
- Glance (Image) – Chapter 7
- Horizon (Dashboard) – Chapter 9
Chapter 11 discusses how to provision OpenStack in Data Centers and discusses the tools and techniques for automating tasks. The absence of DevStack is notable here.
Chapters 12 and 13 cover Monitoring and Troubleshooting respectively.
Most of the 100-odd tasks are written in a three-tiered Getting ready / How to do it / How it works format. It is not a book you would read from start to finish; instead you would pick tasks that are important to you. However, though there are several screenshots and code snippets, there is not a single diagram, either block or network. This is another major shortcoming in the book. One would expect at least a few of the How it works sections to have diagrams to illustrate, conceptually, how the task was realized, such as the flow of packets between VMs in Chapter 10 (OpenStack Networking).
However, it is a good resource for monitoring and troubleshooting tasks and might serve your needs there. Otherwise, my biggest complaint of OpenStack Cloud Computing Cookbook was that it was largely obsolete on the day it was released.
My 2013 Goals
We are two weeks into 2013, so these goals might appear a bit late, but are better that way than never being made. I’m limiting these goals to the professional arena as most of the readers probably won’t care whether I learned French, took 30 wickets in my club’s summer cricket league, or learned how to make the perfect cappuccino.
With that said, here are the professional goals that I will strive to achieve in 2013:
- Immerse myself in OpenStack and its Quantum component. Specifically, I want to build a cloud in my home lab and create complicated scenarios, including, but not limited to:
- Create virtual Data Centers
- Easily spin off VMs and move them across L2 and L3 domains
- Build and configure Open vSwitch and a Floodlight OpenFlow controller to achieve the tasks above
- Document my findings and release them to the public in easy-to-understand videos and screencasts.
- Watch all of Ivan Pepeljnak’s webinars. So far I’ve only watched about a third.
- Attain a working knowledge of Python via Codeacademy.
- Recertify my CCIE status.
- Play a major role in building a product.
I’ll revisit in about a year to see how I fared!
Brief Observations on the State of Networking in Pakistan
I was in Karachi, Pakistan recently for brief visit during the Christmas holidays. Though the purpose of my visit was personal, I did manage to squeeze in some time speaking to professionals who are intimate with the state of networking in Pakistan. In particular I spoke with one individual at Cisco Pakistan who did not wish to be named, but is very familiar with the largest networks in Pakistan.
First, a brief word about telecommunications. Mobile networks in Pakistan currently utilize GPRS and EDGE technologies. Plans to roll out 3G and pseudo 4G technologies have been put on hold. However, broadband speeds to homes and offices have improved significantly over the years, with WiMAX deployments common in Karachi.
Amongst the various ISPs in Pakistan, the biggest player by far is PTCL, which, as of 2006, is a semi-private corporation. PTCL is a Cisco shop that is investing heavily in L2 and L3 MPLS backbones for their customers. For many years, up into the mid-2000s, VSAT communications and dialup were the only means of Internet connectivity. So it was refreshing to see this step being taken.
High Availability is a tough ask in Pakistan with very few enterprises deploying redundant links or nodes. The exceptions are the larger banks. Generally speaking, it has been difficult to educate CIOs in Pakistan on the need for high availability. Likewise, structured cabling and cooling in Data Centers is often neglected or simply misunderstood.
On the technology front, the biggest banks in Pakistan are among the few to deploy Nexus 7Ks. Service Providers such as PTCL deploy CRS’. Virtualization has also yet to make a significant penetration in Pakistan Data Centers. Only the largest banks carry ESX licenses. My questions about SDN, overlay networks, and private clouds met bemused expressions.
However, the country has no shortage of talent. The number of universities that offer degrees in computer science and computer engineering has increased significantly since the early 1990s. The past 20 years has seen some brilliant professionals rise from Hamdard Institute of Information Technology (HIIT), Usman Institute of Technology (UIT), Ghulam Ishaq Khan Institiute of Engineering Sciences and Technology (GIK), and the School of Electrical Engineering and Computer Sciences (SEECS) at the National University of Science and Technology (NUST). R&D work in engineering sciences, unlike that in the natural sciences, is of a much higher quality and comparable to any international institute.
Take, for example, a startup incubated out of NUST, called xFlow Research, which is doing fantastic work in porting Open vSwitch to the Marvell xCat and LION platforms. On the Open vSwitch mailing list archives, about 10% of the contributions come from Pakistanis.
Clearly, despite all the challenges that Pakistani enterprises face with proprietary offerings from pure-play networking vendors and a politically unstable environment, the open source world offers a lot of potential to Pakistan networking industry. I wouldn’t be surprised if 2013 saw some major contributions to OpenStack being made by Pakistani companies.
Umair Hoodbhoy - Multi-Cloud, Networking, and Kubernetes 