Welcome!

SDN Journal Authors: Stefan Bernbo, Michel Courtoy, Amitabh Sinha, Mike Wood, Liz McMillan

Related Topics: SDN Journal, Java IoT, Linux Containers, Containers Expo Blog, @CloudExpo

SDN Journal: Blog Feed Post

Controller Federations: Cluster by Proximity or Service?

Most people understand that typical large-scale deployments are likely to utilize a multi-controller architecture

As SDN moves closer to large-scale deployments, the issue of controller scaling is becoming a hotter topic. The consensus seems to favor some form of distributed cluster environment, likely in the form of federated clusters. But how should these federations be formed?

The first thing to think about is the blast radius for controllers. Even if a controller could scale to manage every node in the network, it is unlikely that you would want that to be the design. It simply creates too large a maintenance and failure domain. Even with a redundant controller, the issues with expansive failure domains are prohibitively scary.

So most people understand that typical large-scale deployments are likely to utilize a multi-controller architecture. But how do you decide how many controllers you need?

The easiest way to think about the problem is by geography. You can take a number of switches or routers that are in relative close proximity and manage them under a single controller. This is particularly easy to do when the selected geography spans a reasonably manageable size of similar devices. A typical example might be a set of top-of-rack switches all managed under a single controller. To reduce the likelihood of a catastrophic failure, you might double up on the controller and provide multiple management connections back to the network.

But are there other ways to think about controller attachment beyond just proximity?

Imagine a case where you select a controller not because it is a natural upward extension of the physical devices but because it provides useful abstractions derived from the applications or services. Fundamentally, this would suggest a controller choice that is top-down rather than bottom-up.

It could be that a particular controller is especially good at content serving. You want to use this controller because it uses protocols like ALTO and OpenFlow to do intelligent content routing. The point of the controller is to deploy an application, so this controller might not be terribly useful in managing individual device configuration. Additionally, the network over which the content must ultimately flow might consist of a bunch of disparate devices from a handful of vendors.

In this case, the controller is more concerned with the overarching service than with managing the individual devices. The blast radius here changes. If the controller fails, the meaningful way to think about what is impacted is from a service perspective rather than a straight box perspective. It could very well be that the network is still functional for other services, but if this controller goes down, anything related to the content request routing service is impacted.

In this type of environment, there is actually a gap in the service controller; it is incapable of performing all of the management (provisioning, monitoring, and troubleshooting) capabilities that might be required for the specific devices under management. The controller is oriented to perform the specific service exceedingly well, but it lacks the individual configuration hooks to be used as a general provisioning and management device.

This is important. The controller is not necessarily an adequate network management device. It is instead a service controller (or maybe an over-the-top controller). And for architects who want to maintain management control, they might need to augment the service controller with other controllers that provide more specific device support.

In this type of architecture, it is possible to have multiple controllers managing the same set of devices. One controller can provide general support, while others are more service-oriented.

A hybrid architecture like this changes the notion of blast radius for sure. Failures and maintenance events are bounded by the edge of the service. But this also changes the notion of a federated controller cluster. Controller domains need not necessarily be non-overlapping sets of boxes that are separated primarily by their proximity to each other (or the controller).

In part, this is how Plexxi views the controller space. We have been actively working to push our notion of application abstractions into the open source community. If we do that, the question people ask is: will OpenDaylight become the controller of record for Plexxi?

This question is far more subtle than people might imagine. Will we ever use OpenDaylight as the primary controller for Plexxi? Well, first, what does that really mean? Is OpenDaylight ever going to be able to serve as a single point of administration for the entirety of a Plexxi deployment? Probably not. OpenDaylight doesn’t want to be in the business of device management. Trying to keep up with configuration options for all the devices that ODP supports would be nauseatingly difficult.

But does that mean that Plexxi doesn’t expect to use OpenDaylight? We absolutely believe that ODP will be successful. We want people using ODP in heterogeneous environments to be able to interface with ODP as a primary controller. Services provisioned (or actions taken) from ODP ought to extend into the Plexxi devices and yield meaningful results. In this case, Plexxi Control acts as a point of integration, and it creates an instance of a cluster federation. Plexxi Control would be subordinate to ODP in the general case here, allowing users to perform overarching tasks from ODP and manage more specific details of the Plexxi deployment from Plexxi Control.

What we end up with is a hybrid controller environment where customers are potentially using two (or more) controllers to manage the same set of devices. What is the distinction for those controllers? It is likely to be more task or service-oriented rather than proximity – use the right controller for the right job. Is this the future of federated control for SDN? It is certainly one possibility.

To see Plexxi’s integration with OpenDaylight, tune into the March 14 live demonstration on SDNCentral. For full details, check out the event registration page.

[Today’s fun fact: The microwave was invented after a researcher walked by a radar tube and a chocolate bar melted in his pocket. I wonder how spray paint was invented.]

The post Controller federations: Cluster by proximity or service? appeared first on Plexxi.

Read the original blog entry...

More Stories By Michael Bushong

The best marketing efforts leverage deep technology understanding with a highly-approachable means of communicating. Plexxi's Vice President of Marketing Michael Bushong has acquired these skills having spent 12 years at Juniper Networks where he led product management, product strategy and product marketing organizations for Juniper's flagship operating system, Junos. Michael spent the last several years at Juniper leading their SDN efforts across both service provider and enterprise markets. Prior to Juniper, Michael spent time at database supplier Sybase, and ASIC design tool companies Synopsis and Magma Design Automation. Michael's undergraduate work at the University of California Berkeley in advanced fluid mechanics and heat transfer lend new meaning to the marketing phrase "This isn't rocket science."

@CloudExpo Stories
"With Digital Experience Monitoring what used to be a simple visit to a web page has exploded into app on phones, data from social media feeds, competitive benchmarking - these are all components that are only available because of some type of digital asset," explained Leo Vasiliou, Director of Web Performance Engineering at Catchpoint Systems, in this SYS-CON.tv interview at DevOps Summit at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
21st International Cloud Expo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy. Me...
SYS-CON Events announced today that DXWorldExpo has been named “Global Sponsor” of SYS-CON's 21st International Cloud Expo, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Digital Transformation is the key issue driving the global enterprise IT business. Digital Transformation is most prominent among Global 2000 enterprises and government institutions.
SYS-CON Events announced today that Datera, that offers a radically new data management architecture, has been named "Exhibitor" of SYS-CON's 21st International Cloud Expo ®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Datera is transforming the traditional datacenter model through modern cloud simplicity. The technology industry is at another major inflection point. The rise of mobile, the Internet of Things, data storage and Big...
Kubernetes is an open source system for automating deployment, scaling, and management of containerized applications. Kubernetes was originally built by Google, leveraging years of experience with managing container workloads, and is now a Cloud Native Compute Foundation (CNCF) project. Kubernetes has been widely adopted by the community, supported on all major public and private cloud providers, and is gaining rapid adoption in enterprises. However, Kubernetes may seem intimidating and complex ...
"Outscale was founded in 2010, is based in France, is a strategic partner to Dassault Systémes and has done quite a bit of work with divisions of Dassault," explained Jackie Funk, Digital Marketing exec at Outscale, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"DivvyCloud as a company set out to help customers automate solutions to the most common cloud problems," noted Jeremy Snyder, VP of Business Development at DivvyCloud, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"We focus on SAP workloads because they are among the most powerful but somewhat challenging workloads out there to take into public cloud," explained Swen Conrad, CEO of Ocean9, Inc., in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"We are still a relatively small software house and we are focusing on certain industries like FinTech, med tech, energy and utilities. We help our customers with their digital transformation," noted Piotr Stawinski, Founder and CEO of EARP Integration, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"I think DevOps is now a rambunctious teenager – it’s starting to get a mind of its own, wanting to get its own things but it still needs some adult supervision," explained Thomas Hooker, VP of marketing at CollabNet, in this SYS-CON.tv interview at DevOps Summit at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"We've been engaging with a lot of customers including Panasonic, we've been involved with Cisco and now we're working with the U.S. government - the Department of Homeland Security," explained Peter Jung, Chief Product Officer at Pulzze Systems, in this SYS-CON.tv interview at @ThingsExpo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"We're here to tell the world about our cloud-scale infrastructure that we have at Juniper combined with the world-class security that we put into the cloud," explained Lisa Guess, VP of Systems Engineering at Juniper Networks, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
Your homes and cars can be automated and self-serviced. Why can't your storage? From simply asking questions to analyze and troubleshoot your infrastructure, to provisioning storage with snapshots, recovery and replication, your wildest sci-fi dream has come true. In his session at @DevOpsSummit at 20th Cloud Expo, Dan Florea, Director of Product Management at Tintri, provided a ChatOps demo where you can talk to your storage and manage it from anywhere, through Slack and similar services with...
"We were founded in 2003 and the way we were founded was about good backup and good disaster recovery for our clients, and for the last 20 years we've been pretty consistent with that," noted Marc Malafronte, Territory Manager at StorageCraft, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"We are an IT services solution provider and we sell software to support those solutions. Our focus and key areas are around security, enterprise monitoring, and continuous delivery optimization," noted John Balsavage, President of A&I Solutions, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
"We want to show that our solution is far less expensive with a much better total cost of ownership so we announced several key features. One is called geo-distributed erasure coding, another is support for KVM and we introduced a new capability called Multi-Part," explained Tim Desai, Senior Product Marketing Manager at Hitachi Data Systems, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
There is a huge demand for responsive, real-time mobile and web experiences, but current architectural patterns do not easily accommodate applications that respond to events in real time. Common solutions using message queues or HTTP long-polling quickly lead to resiliency, scalability and development velocity challenges. In his session at 21st Cloud Expo, Ryland Degnan, a Senior Software Engineer on the Netflix Edge Platform team, will discuss how by leveraging a reactive stream-based protocol,...
SYS-CON Events announced today that Calligo, an innovative cloud service provider offering mid-sized companies the highest levels of data privacy and security, has been named "Bronze Sponsor" of SYS-CON's 21st International Cloud Expo ®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Calligo offers unparalleled application performance guarantees, commercial flexibility and a personalised support service from its globally located cloud plat...
DevOps at Cloud Expo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 21st Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to w...
Internet of @ThingsExpo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 21st Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago. All major researchers estimate there will be tens of billions devic...