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Exclusive: Q&A with Madhu Venugopal, OpenDaylight Hydrogen MVD, and Brent Salisbury, Network Admin Turned Developer

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Exclusive: Q&A with Madhu Venugopal, OpenDaylight Hydrogen MVD, and Brent Salisbury, Network Admin Turned Developer

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Exclusive: Q&A with Madhu Venugopal, OpenDaylight Hydrogen MVD, and Brent Salisbury, Network Admin Turned Developer

Earlier this month, OpenDaylight released Hydrogen, the organization’s much-anticipated first SDN platform release. OpenDaylight recognized Madhu Venugopal, senior principal software engineer with Red Hat and one of the architects of the OpenDaylight controller, as its Most Valuable Developer on the Hydrogen project. SDNCentral talked recently with Venugopal, who is known among his peers for enabling others to be successful by providing insight and guidance.

Joining us for the conversation was Brent Salisbury, who is also known as the network admin who became an SDN developer. Brent now works as a software developer on the OpenDaylight project for Red Hat. He blogs at NetworkStatic.net with a focus on disruptive technologies.

Together we discussed collaboration in the networking community, learnings from the Hydrogen project, and advice for professionals who want to transition to SDN.

SDNCentral: Madhu, congratulations on winning the MVD award for the Hydrogen project! How do you feel about it?

Venugopal: Thank you. I am deeply humbled and honored to receive this award. I feel this is not a recognition for me as a contributor to the project, rather, to recognize and reward the open source way of collaborating with the community towards a common goal.

I never had an opportunity to work in such a collaborative atmosphere in the field of networking prior to the first Open Networking Summit conference in 2011. Immediately after this inspiring conference, we found ourselves experimenting on the SDN controller project. The very first thing we observed was the amount of open information that we got from the community. I am extremely fortunate to know so many inspirational figures in our field, directly or indirectly. There is no OpenDaylight, or SDN for that matter, without these great leaders and the unconditional willingness to share their thoughts and experiences.

SDNCentral: Brent, one of the key reasons Madhu won the award was because of the assistance he’s provided other developers on OpenDaylight. How did you come to meet Madhu?

Salisbury: I first met Madhu virtually on the OpenDaylight IRC channel and then met him face to face at an industry conference. He operates at such a high level technically in software development and network architecture, coupled with an equally high social IQ for building and leading teams. It truly makes him a catalyst in the industry.

SDNCentral: Brent, how did Madhu engage you on OpenDayligt? What help did he provide?

Salisbury: Even before I meet Madhu face to face, there were hackathons where the awesome West Coasters would take pity on us geographically challenged East Coasters, and they would carry around iPads and get a stream going for us. Regardless of the topic, there was Madhu doing code walk throughs for those of us just getting up to the code base.

From there, we both agreed that a purely standards/RFC open source based network virtualization implementation was a gap in the industry. We really wanted to take as much advantage of what we consider the reference SDN datapath implementation in Open vSwitch.

SDNCentral: Brent, at the OpenDaylight Summit, you were referred to in the keynote as the “network admin who became a developer.” How do you feel about that?

Salisbury: To even be associated with a project like OpenDaylight, and even broader, the fledging networking community, is beyond words. I used to send [SDN leaders] e-mails thanking them for their work and leadership, and each of them always took the time to reply. They probably thought I was crazy – a random guy working as a network architect who saw the challenges we face up close, but never had the tools or means with which to change them.

SDNCentral: Madhu, what drives you to help other developers?

Venugopal: What I learned from leading SDN framers is the relentless commitment to collaboration and community that created this disruption. There isn’t a day that goes by when I don’t think of them, and it is natural to work with the community with this mindset. This is just our way of paying it forward.

One of the main reasons I joined Red Hat is to be part of that DNA structure that drives innovation through openness. It’s natural for me to collaborate with other developers in the OpenDaylight community because they share the same passion as I do.

SDNCentral: Madhu, why are you so passionate about OpenDaylight?

Venugopal: I am extremely passionate about software development and working with community. Regardless of corporate affiliation, we feel like a group of developers who are collectively putting our best foot forward as one to concretely deliver new ideas and vehicles for innovation. OpenDaylight is the platform that helps me deliver on my passion. It has some of the smartest minds in the networking industry and world-class programmers all growing and learning from one another.

SDNCentral: Do either of you have any interesting stories, anecdotes, or key learnings from getting Hydrogen out the door?

Venugopal: (Laughing.) A lot of stories and anecdotes. Most of the funniest ones happened during our crazy Google Hangout sessions during the middle of the night (PST/3 a.m. EST).

Salisbury: We have a bunch of ridiculous sleep-deprived stories, but one worthy of note is that our OVSDB team mascot is a vacuum cleaner. We worked around the clock, and at the same time each night Madhu’s Roomba, a robot/vacuum cleaner, would start – always when we were recording how-tos for developers to get started, or debugging code and whatnot. It makes Madhu crazy, and it was a much-needed laugh at times. As much fun as we had, here are my key take-aways:

  • Developers are in fact the backbone of OpenDaylight.
  • “Open” comes before “source” in open source. It is much more important to be open and collaborative than dumping source code.
  • “Code is the coin of the realm,” as Dave Meyer (OpenDaylight board member) says. Collaborative and open development practices transform good code to quality code.

SDNCentral: What would you avoid the next time round? What would you do more of?

Salisbury: As for what we would do more of, we would still put a lot of hard work into building solutions for the challenges facing next-generation compute, storage, and network requirements. We also would continue to put a lot of hard work into growing the community. There is a lot of work in building a collaborative and open community, but we are laser focused on achieving this.

Venugopal: As for what we would like to avoid, during the development cycle, we would avoid error-prone manual configuration where automation performs a better job, meaning we would have to make better use of continuous integration and automated release management. We also would avoid inter-project integration until the last minute of the release. We could achieve this by following solid software development and integration practices.

SDNCentral: What do you two see as the future of SDN?

Salisbury: Openness and community will be the underpinnings of whatever it is we come out of this evolution with. OpenStack set the stage, and much of the work we are doing is focused on complementing that.

Carriers cannot absorb the exponential growth of the NetFlix effect without radically changing their models. The growth of both the network software developer and the network engineer/architects coupled with the relationships that are made will profoundly change networking as we know it today. Open source gives anyone the chance to disrupt status quo.

Venugopal: SDN is the future of networking, so I take the question on the future of SDN as how SDN will evolve from its current form. I have been dead wrong in many of my predictions in the past – yes, I bought a house in 2008 – hence I would rather express my hope on how SDN will evolve.

SDN for me is network redemption. I hope SDN will work itself out in redeeming the seven deadly sins of our networking past. I think we are starting to see some signs of that. Ultimately, I really hope this SDN momentum will help deliver on the promise of operational simplicity and spurs more innovation in our next-generation digital world.

SDNCentral: Brent, what advice would you give network admins who are looking to transition to the new world of SDN?

Salisbury: First things first, learn Linux. I don’t just say that because I work at Red Hat. Almost all network operating systems today – whether located in the control, management, or data plane – are or will be using Linux. These are back-end components that differentiate in economies of scale and rock-solid performance. The Linux kernel is the crown jewel of open source and a marvel unto itself.

Secondly, learn compute virtualization and how these resources are being networked today. There is an ever-growing gap between virtual ports and physical ports from the evolution in the data center and the explosion of wireless devices.

Lastly, for those looking to differentiate themselves and even reinvent themselves, start or increase the amount of programming you do from day to day. Simple automation can be started or improved in any network shop. Starting with loosely typed languages like Python will be the right tool, OpenStack is a great example. For a bit more of a challenge, start hacking on Java or C and getting to know codebases in projects like OpenDaylight and Open vSwitch. At the end of the day, the more you give away, the more that comes back.

SDNCentral: Madhu, what advice would you give new developers who are still on the fence about getting started with OpenDaylight?

Venugopal: With 12 projects and growing, OpenDaylight codebase has grown in size over the past 10 months. It certainly will be daunting if any new developer tries to consume everything OpenDaylight has to offer. It’s best to associate with a project of interest, take up something small, and go through the process of hack, build, commit, and merge. I have seen many developers with very little programming experience get started quickly and who now are major contributors to some of the existing projects.

For programmers, both novice and experienced, my advice would be to come and hang out with us on the IRC channel. The OpenDaylight developers are extremely helpful, and they know the importance of building the community. All of us will advise you to get your hands dirty by jumping in. If the developer’s initial inertia is due to the programming language, then it’s best to download existing pre-built VMs and try out the end product. Here are some final thoughts and resources:

  • Join us at IRC channel #opendaylight, #opendaylight-ovsdb, etc. at irc.freenode.net;
  • Join the OpenDaylight mailers
  • Participate in OpenDaylight Technical Steering Committee and Technical Work Stream meetings, which are open to everyone;
  • Participate in hackfests and virtual hackfests that occur on IRC along with the great conversations in channel that happen daily.

SDNCentral: Thank you both for your time today.

Venugopal and Salisbury: You’re welcome. Thank you for having us.


"I love writing authentication and authorization code." ~ No Developer Ever. Try Okta Instead.


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