The Network is the Bottleneck: Stacks and Flows Are the Answer
October 2nd, 2013 By: Rich Miller
ORLANDO, Fla. - It’s the age of DevOps. Rapid iteration is all the rage. Developers are writing and deploying new applications faster than ever, rolling out new features in real time. And then …
“What happens is that they run into the network,” says Lori MacVittie. “The network is the roadblock. It’s slowing things down.”
MacVittie, the Senior Product Manager for Emerging Technologies at F5 Networks, discussed new strategies for automating network management Tuesday in a session at Data Center World Fall. Cloud software stacks and software-defined networking (SDN) are two approaches to making networks easier to manage and configure.
In a presentation titled “Stacks and Flows: Decoupling Hype from Reality,” MacVittie familiarized data center managers with the technologies that can help automate networks – a critical step in making data centers more agile, which has been a key theme of this week’s conference.
Wanted: Network Automation tools
“The network is the bottleneck in the data center,” said MacVittie. “It’s the last of the three groups (servers and storage are the others) that needs to be automated.”
Many companies are sorting out how to scale their server and storage infrastructures. Meanwhile, MacVittie noted that 54 percent of enterprises report adoption of some level of DevOps, in which apps and updates are being shipped more frequently. The network is critical to everything, and not as flexible in adapting to frequent changes.
“We need to made the network as elastic as the rest of the infrastructure,” said MacVittie. “Everybody’s pushing on you. So you want to be more agile and flexible and create new services.”
Opening Up the Network
The networking sector has long been dominated by a handful of vendors focused on switches running on proprietary software. SDN seeks to use OpenFlow and related technologies to separate the hardware and software, typically by shifting management functions to a commodity server running open source software that can manage the switch.
That would give data centers the option of using more commodity hardware and open source software in their network infrastructure.
“If OpenFlow takes off, it’s going to supplant a lot of your existing network management systems,” said MacVittie.
‘A Nascent Market’
The reality check? For all the buzz, SDN technologies are emerging and immmature. “Pretty much the entire market is still in flux,” said MacVittie. “Expect to see that for another couple of years. it’s a nascent market.”
The good news: that gives data center managers time to get up to speed on SDN and what it can mean to their efforts to transform their facilities.
While a growing number of vendors are rolling out gear that can use OpenFlow, MacVittie urged the audience to pay attention to the Open Daylight Project, which may further expand the options for network management. Open Daylight still uses OpenFlow, but has added extensions to incorporate hardware that isn’t OpenFlow enabled, which can now be automated and included in OpenDaylight architectures.
“You can still get SDN for your equipment that might be proprietary and closed,” said MacVittie.
What About Stacks
Then there are the stacks – cloud software platforms like OpenStack, CloudStack, OpenNebula and Eucalyptus. These platforms tie together hardware, a control layer and a presentation layer, and are extensible.
“The goal of the stack is to automate the data center,” said MacVittie. “What the stacks try to do is use the APIs the vendors are providing today. You can create a plugin that goes into the stack and runs the equipment.”
For all the automation, some networking challenges will remain.
“You can’t automate taking a plug out and putting it back in,” said MacVittie.
I like the focus on automation and the rise of DevOps in a networking context. I think that is exactly the right direction.
But the more I talk about DevOps with people and read about it in articles contributed to by networking people, the more I am convinced that the application of DevOps to networking is not really well understood.
There seems to be this belief that applying “DevOps” to networking is simply extending the tools and concepts to routers and switches. But the problems in compute and storage are not the same as those in networking.
With servers, the issue is provisioning and deployment – turning up new capacity to support applications. You start with the application and you bring the compute and storage sides in tow. But with networking, it is not about new device bringup. The issue is edge policy. And the real point is that the edge policy is tied to applications.
If that is the case, the entry point is not the router or switch but rather the application. And ideally the automated workflows would be tied to the server activity, not just launched as an automated network activity.
If we treat the network like we treat compute, we will get some savings from automation. But we will have missed the entire point of data center infrastructure: it all works in concert to support the application. Right now, we aren’t even having the right dialogue unfortunately.
-Mike Bushong (@mbushong)