Day & Zimmermann Logo
Industry: Utility
Location: United States
Download Full Story

Day & Zimmermann increases availability of business-critical systems


  • Raised availability to 99.995% for business-critical SAP HANA database systems.
  • Enabled a 90% reduction in manual configuration for new SAP environments.
  • Saved $70k+ by avoiding the need for hardware-based high availability solutions.
  • Reduced unplanned downtime to 30 minutes a year.


Day & Zimmermann operates in peopleintensive industries such as construction and engineering, operations, staffing and security. With a total workforce of 46,000 employees and contractors at over 150 locations worldwide, it’s crucial to ensure that all its people get paid accurately and on time. That’s why the company relies on SAP applications to manage its payroll and other business-critical processes.


As a major construction and engineering company with projects all-around the world, Day & Zimmermann relies on SAP applications to ensure its employees and contractors get paid on time. To ensure its core SAP HANA databases are online 24/7, the company built a highly available cluster using SUSE Linux Enterprise Server (SLES) for SAP Applications — reducing unplanned downtime to less than 30 minutes per year.

The Challenge

Day & Zimmermann has been running its business on SAP since the early 2000s, and originally used Oracle as its database platform. Over time, the Oracle environment proved to be an expensive option, so when SAP began encouraging clients to move to its new SAP HANA database platform, Day & Zimmermann decided to migrate.

It was vital to ensure that the new environment would deliver the high levels of availability that the company’s SAP systems — especially its payroll application — require. Since the company operates in almost every time zone around the world, there is simply no good time for downtime; users need to be online 24/7.

“The High Availability Extension in SUSE Linux Enterprise for SAP Applications is phenomenal. The failover is completely automatic, it only takes a few seconds, and it has already helped us avoid several long outages.”

SUSE Solution

SAP recommended running the new SAP HANA system on SLES for SAP Applications, and as the Day & Zimmermann IT team began working with this new operating system, they quickly realized that it was the right choice.

“When you want to set up a new SAP database server, there’s usually a great deal of legwork,” says Chris Nega, manager, systems engineering at Day & Zimmermann. “You have to set dozens of operating system parameters and it can take hours of research to find the right settings.

“With SLES for SAP Applications, the ease of installation is astounding. 90% of the parameters are set automatically, so the configuration effort is significantly less. That’s the real advantage of the close relationship between SUSE and SAP.”

The company also uses SUSE Manager to simplify other aspects of server management, such as patching.

“For production systems, every machine has to be at the same patch level,” says Nega. “Previously, we had to log in to each machine individually to install patches. With SUSE Manager, you can just click a button to install the same package everywhere. It’s a guarantee that you are going to get the environment you expect.”

Day & Zimmermann also decided to take advantage of the High Availability Extension within SLES for SAP Applications. The company’s production SAP HANA environment runs on a multi-node cluster, with the SUSE Linux Enterprise High Availability Extension providing automatic, nearinstant failover between primary and secondary nodes if a fault occurs.

“The High Availability Extension in SLES for SAP Applications is phenomenal,” says Nega. “Failover is completely automatic, it only takes a few seconds, and it has already helped us avoid several long outages.”

The Results

SLES for SAP Applications provides an environment that fully meets Day & Zimmermann’s needs for both business continuity and ease of management.

“When your systems are properly configured and clustered, and your patches are up-to-date, there’s much less that can go wrong,” says Nega. “We hardly ever need to call the SUSE support team, although when we do, they are fantastic. The last time we called them, it was the best support experience we’ve encountered in the past several years.”

With its clustered architecture, Day & Zimmermann has seen availability rise to around 99.995%. Over the past four years, it has experienced just two hours of unplanned downtime.

“We had one vendor try to sell us a hardware-based high availability solution that cost $70,000,” says Nega. “With SUSE, the high availability features are built directly into the operating system, so there’s no additional cost or complexity. It’s really a no-brainer.”

As the company’s IT landscape continues to grow, SLES has become a corporate standard for all new applications — not just SAP. For example, the company recently set up an AMD EPYC 3-node Veeam scale-out backup repository that runs on the SUSE operating system.

“As our team has grown familiar with SLES, we’ve been impressed by how easy and simple to administer it is, so we’re starting to architect our solutions more in that direction,” concludes Nega. “If we can use Linux to reduce our reliance on proprietary operating systems and licensing, we’ll be able to unlock significant cost savings.”