Walmart Tackles Major IT Changes with Confidence Across a Huge Legacy Environment: “Go Big or Go Home, Right?”

Walmart is synonymous with retail. The biggest retailer in America and the world, the multinational chain deals with IT and DevOps on a huge scale. In order to solve and prevent drift in their legacy environment comprising thousands of servers in thousands of stores, the Walmart IT team chose Puppet to standardize configuration management.

Benefits of Using Puppet:

~49,000 servers managed

by Puppet.

543.58 resources per node

managed with PuppetDB.

Major changes made in hours

– down from “four weeks to never.”

Saved 3 weeks per build

by automating the addition of DBA user groups.

Challenge: 100,000 Servers, 11,000 Stores + One Standardization Effort

Martin Jackson of the Walmart infrastructure team called their Puppet initiative “taming the brownfield.” In their legacy systems (or “brownfield”), they wanted to control drift, manage a huge number of configurations across complex infrastructure, and report on changes to their IT environment.

“The configuration management team’s purpose at Walmart is to empower other teams – our customers – to deliver more quickly, more consistently, and more transparently,” Martin Jackson of the Walmart infrastructure team said.

Watch: 5 Lessons Walmart Learned About Using Puppet

To deliver that degree of service, Jackson said their team wanted to invest in intelligent decisions to support their system architecture. “Our customers depend on our systems to be available,” he added, “and we have to make sure that they stay available.”

And at the same time, they knew that bringing that legacy environment up to a new standard wouldn’t be a simple undertaking. The brownfield in question comprised more than a half dozen operating systems running on hundreds of thousands of servers, including some 50,000 in 11,000 stores across the globe.

With two dedicated Puppet code developers and three more dedicated to tooling and architecture, they brought 1,000 active nodes in their data centers under Puppet management. Then they set their sights on scaling to 30,000 active nodes within two months.

“We knew right at the beginning of our Puppet journey that we were gonna go big,” Jackson said. “Go big or go home, right?”

Results: Drift Managed, Engineers Empowered + Big Changes Made with Confidence

“When you’re dealing with fire-and-forget change management systems, the scary thing is that you can’t be sure the change you just made is going to stick. Puppet gives you the confidence that the things you set are going to stay set that way ... and then when you decide you’re going to change it with Puppet, it's very easy and very straightforward.” 
- Martin Jackson, Information Systems Division, Walmart



By their target date, Walmart’s Puppet team had brought more than 48,000 nodes under Puppet management. That gave them the confidence to move from known state to known state, rather than relying on ad hoc changes, unaddressed drift, and misconfiguration.

They quickly began utilizing hundreds of Puppet modules from the Forge, adding people to develop Puppet content and tooling, and running an average of 543.58 resources per node with PuppetDB.

“We adopted Puppet for the particular purpose of controlling drift in a large, legacy brownfield environment,” Jackson said. “It’s doing that job fantastically well across multiple OS platforms, across huge geographic distances – stores thousands of miles away are using the same infrastructure – and it’s all working.”

For Jackson and his team, adopting Puppet was an extension of Walmart’s corporate ethos.

“We're Walmart,” he said. “Our corporate mission is to save money so you can live better. In order to do that, we in the IT function have to always be on the lookout for more ways to do more with less, to do the same things at a lower cost ... so that we can give you, the customer, a lower price and a better shopping experience.”

Standardize and Secure to Enable Better Work in Your IT Environment

Contact the Puppet team or request a demo today to find out how Puppet can help standardize change management for better DevOps in your enterprise IT.