4-page Case Study
Posted: 11/15/2013
Rate This Evidence:

Telekom Slovenije Telecom Company Uses File-Based Storage to Reduce Costs, Not Performance

Telekom Slovenije customers demand always-available telecommunications services. To ensure that its storage solutions reliably and efficiently serve data to its critical telecom systems, Telekom Slovenije had to balance performance with price—until now. Today, the company uses a less-expensive alternative to its existing SAN storage solution that performs equally well. The latest storage technologies in Windows Server 2012 R2 offer a Server Message Block-based storage solution that uses the File and Storage Services server role running in a failover cluster. Telekom Slovenije could repurpose file servers acquired from a merger to build this cost-effective alternative solution. With new, cloud-ready, virtualized file-based storage, the IT staff can begin building private and public clouds with customers, partners, and subsidiaries, while simplifying storage management and reducing costs.

Telekom Slovenije, with its subsidiaries, is the integrated telecommunications service provider playing a major role in the telecommunications business in Slovenia. The company is recognized as the leader in introducing and joining together new generations of mobile and fixed communications and multimedia contents. In July 2011, Telekom Slovenije merged with mobile service provider Mobitel to consolidate its position in the Slovenian market and boost responsiveness to new business opportunities. Today, Telekom Slovenije services are synonymous with high quality, fast and reliable mobile and broadband networks, and superior user experience.

The IT staff at Telekom Slovenije has been working hard to consolidate disparate IT solutions and infrastructures since the merger, which saw more than 1,000 Mobitel employees, 1,600 PCs, and 500 servers added to the jurisdiction of an eight-member network team that already managed the 2,000 employees, 3,500 PCs, and 500 servers at Telekom Slovenije.

Recently, Telekom Slovenije began looking for ways to reduce the amount of time that its IT staff spent managing the diverse storage solutions inherited from the merger and to define an enterprisewide storage strategy going forward. “We want to consolidate systems and applications from the merger to run in failover clusters within private clouds to boost availability and manageability,” says David Koprivnikar, System Engineer Specialist at Telekom Slovenije. “As a telecom company, our customers expect continual uptime for our services. Our main storage solution is a SAN solution in our two main locations, and we have older storage technologies scattered in another three sites across the country. Right now, every storage device connects to a storage stack through expensive Fibre Channel and iSCSI connectivity.”

* Storage requirements grow faster than IT budgets. But with the latest file-sharing storage capabilities in Windows Server 2012 R2, we’re excited to see performance and manageability close to costly SAN solutions. *

David Koprivnikar
System Engineer Specialist, Telekom Slovenije

For its failover clusters running in a virtualized environment, Telekom Slovenije needed to deploy a shared storage solution that enables simultaneous access by multiple servers. Traditionally, this technology has been available through expense storage area network (SAN) solutions and iSCSI or Fibre Channel connectivity connecting storage disk trays to individual nodes.

“We didn’t have the technology to manage storage economically for virtual machines hosted in a failover cluster running in active-active mode,” says Koprivnikar. “For some of our business-critical solutions, we could continue with our SAN-based storage. But to save money, we needed a cost-effective alternative for the rest of our systems. As a result of our merger, we had a lot of industry-standard hardware that we needed to repurpose. We thought of finding a way to use it for a different approach to storage.”

Telekom Slovenije decided to join the Rapid Deployment Program (RDP) for Windows Server 2012 R2 to explore the Microsoft alternative to a SAN solution—Server Message Block 3 (SMB3) file-based storage where virtual machines running on Hyper-V hosts access shared VHDX files on Windows Server file servers over low-cost Ethernet-based networks. SMB3 is the protocol used by Microsoft for file services. Hyper-V over SMB3 was introduced in Windows Server 2012 and it supports SMB file storage on Hyper-V virtual machines running on industry-standard servers.

“We joined the RDP because we saw a lot of possibilities in the new server technologies related to how to configure and manage storage for private clouds,” says Koprivnikar. “This scenario would also provide an excellent use for the redundant servers that we had from the merger. We could use our servers to build scalable failover clusters running server workloads such as Microsoft Exchange Server, Hyper-V, Microsoft SQL Server, and file servers. ”

Cost-Effective, Highly Available Storage
Of the new server technologies, Koprivnikar is particularly interested in the cost savings and improvements in the SMB3 protocol for server applications introduced by File and Storage Services server role using failover clustering. A File and Storage Services cluster helps ensure that every file server node in a cluster provides continuously available storage access to its compute layer—virtual machines running file-based server applications. Storage Spaces, first introduced in Windows Server 2012, delivers storage virtualization capabilities, so Telekom Slovenije can use industry-standard storage for failover clusters as well as single server deployments. By using the Storage Spaces tiering functionality introduced in Windows Server 2012 R2, the IT staff added both solid state drives (SSDs) and hard disk drives (HDDs) to a storage space and Storage Spaces automatically differentiated between the two types of storage. The tiering functionality in Storage Spaces then moves frequently accessed data to the faster SSD storage and infrequently accessed data to the slower HDD storage. This occurs without any administrator intervention.

By using this design, it is easy for the IT staff at Telekom Slovenije to scale out the Hyper-V compute layer by adding more nodes, without incurring the costs of expensive Fibre Channel host bus adapters in each server. Also, Telekom Slovenije can scale out the storage layer by adding additional disks so that IT staff can add capacity to different pieces of the storage solution independently, depending on their needs.

With the latest Hyper-V file-based storage and failover clusters capabilities in Windows Server 2012 R2, Telekom Slovenije has the foundation for building highly available virtual environments supported by low-cost, highly available storage. During the RDP, the IT staff worked with several new capabilities within Windows Server 2012 R2 that add even more value to failover clustering and file-based storage scenarios.

To support cost-effective guest clusters, Telekom Slovenije used the Windows Server 2012 R2 Shared Virtual Hard Disk feature. By using Shared Virtual Hard Disk, Telekom Slovenije IT staffers configured a failover cluster so that multiple virtual machines can share a VHDX file. Previously, it was not possible for multiple virtual machines to access the same VHDX file and see it as shared storage. “We liked the extra flexibility of creating virtual machine clusters using a shared VHDX file because you don’t have to make storage configuration changes, such as zoning and LUN [Logical Unit Number] masking,” says Koprivnikar.

The IT staff also explored data deduplication capabilities within Windows Server 2012 R2. “We were interested in seeing how, in the latest version of Windows Server 2012, data deduplication can optimize a running virtual machine, something that only SANs used to offer,” says Rok Nemec, System Engineer Specialist at Telekom Slovenije. “I am getting 70 percent reduction in storage required for our file servers now. We also used the CSV [Cluster Shared Volumes] cache, which gives you the possibility to allocate system memory [RAM] of the cluster nodes as cache to improve performance. You can also use data deduplication on CSV with virtual hardware, which will enable us to reduce storage needed for a virtual environment.”

On a failover cluster that uses CSV, virtual machines that are distributed across cluster nodes can all access their Virtual Hard Disk (VHD files or their VHDX files) at the same time, even if the VHD files are on a single storage disk. Consequently, virtual machines can migrate to any node in the cluster without losing access to the VHD files on the shared volume.

Two Distributed Storage Scenarios
During the RDP, the IT team at Telekom Slovenije worked closely with Microsoft Services to build a test environment to evaluate the latest enhancements to Windows Server 2012 R2 storage technologies. The IT team built two file-based storage scenarios at its primary data center to support two clustered Hyper-V workloads 10 kilometers away at the secondary data center. IT staffers used Hyper-V Replica, which replicates virtual machines over IP-based networks to a remote site. “We already had the hardware required in the two data centers, so we configured the RDP storage environments this way to explore how the storage solution performed over distance,” says Koprivnikar. “We were amazed at how well it worked. We are also interested in Hyper-V Replica to maintain high availability by replicating virtual machines across two or even three locations. This level of availability is critical for a telecom company.”

* We liked the extra flexibility of creating virtual machine clusters using a shared VHDX file because you don’t have to make storage configuration changes, such as zoning and LUN masking. *

David Koprivnikar
System Engineer Specialist, Telekom Slovenije

The first storage scenario uses a stand-alone file server with a SAS drive connected to a JBOD array. JBOD is an array of hard disks that haven't been configured according to the redundant array of independent disks (RAID) system. The IT team enabled Storage Spaces tiering functionality on the single file server that used SMB3 to present storage to the Hyper-V node via teamed, 1-gigabyte ports. The second storage scenario featured a two-node File and Storage Services cluster and an existing SAN storage product with Fibre Channel ports. For this scenario, the IT team used CSV and the CSV cache. For each File and Storage Services cluster node, the team allocated four 10-gigabit network interface cards (NICs) to connect to the main network.

Remote Hyper-V Workloads
At the other data center, two Hyper-V nodes support approximately one hundred virtual machines. The team also built a single, two–virtual machine cluster within the multiple virtual machines that access the shared VHDX file. The team added virtual switches on top of two teamed 10-gigabit NICs to provide access to all the virtual machines. Then it added two teamed NICs per Hyper-V node. These NICs were dedicated for storage access (Figure 1).

Using one of the virtual machines that accesses shared VHDX files over SMB3, the IT team tested Microsoft SQLIO Disk Subsystem Benchmark Tool performance with a 20-gigabyte data file and compared the I/O performance to that when the machine was running locally on the File and Storage Services cluster. “With the virtual machine and shared storage, we reached approximately 75,000 IOPS [I/O operations per second] as compared with 85,000 IOPS on the physical server,” says Nemec. “This was an excellent result, considering the first test ran between environments 10 kilometers apart.”

The IT team also tested transparent failover of a running virtual machine after turning off a File and Storage Services cluster node and it worked seamlessly. The team also tested “shared nothing” live migration, a feature introduced in Windows Server 2012 Hyper-V to allow for mobility of virtual machines between Hyper-V nodes without failover clustering or shared storage. “When we saw the virtual machine move from one Hyper-V node to another without CSV, we were very happy,” says Koprivnikar.

On the stand-alone file server within the first storage scenario, the IT team had more than 7 terabytes of extra data, so it tested data deduplication. “We created a file server, turned on deduplication, and started adding data. We hit a 70 percent reduction ratio on that file server, which is very nice,” says Koprivnikar.

By using Windows Server 2012 R2, Telekom Slovenije plans on deploying more instances of file-based storage across the company, especially to support planned private cloud. “I was really surprised at the amount of new capabilities within Windows Server 2012 R2 because it’s not been that long between releases,” says Koprivnikar. “And we had a fantastic experience with Microsoft Services; our contact was very knowledgeable and helped us see the many possibilities in the operating system.”

Figure 1.
Figure 1. Telekom Slovenije tested two file-based storage scenarios
using technologies from Windows Server 2012 R2.File-based storage
is a cost-effective alternative to a SAN storage solution that performs
equally well.

By using the new storage capabilities within Windows Server 2012 R2, Telekom Slovenije gains a cost-effective option for building storage solutions that will make the job of consolidating and optimizing a new, post-merger IT infrastructure easier. “Right now, we are maintaining two legacy storage environments and we are in the process of consolidating four data centers,” says Koprivnikar. “There is a lot of work to do and every technology that helps to do it is welcome.”

IT staffers at Telekom Slovenije are happy about the flexibility that they gain with the option to use highly scalable, file-based storage solutions to support Hyper-V workloads—at significantly less cost than existing SAN storage systems. “Storage requirements grow faster than IT budgets,” says Koprivnikar. “But with the latest file-sharing storage capabilities in Windows Server 2012 R2, we’re excited to see performance and manageability close to costly SAN solutions. All we have to do is add a fast SSD and repurpose our old file servers to achieve the same performance as our existing SAN storage.”

Improved Performance at Less Cost
With a new cost-effective storage option from Microsoft, Telekom Slovenije doesn’t have to balance performance with cost. SSDs are fast but expensive and have comparatively low capacities; HDDs have more capacity and are inexpensive but slower. Because the tiering functionality with Storage Spaces IT staff will allocate SSD resources only to virtual machines running business-critical applications where performance is important, IT staff can boost performance where it counts. The other benefit to Telekom Slovenije is that it now has the option to save money by using HDDs for less demanding solutions.

The new storage options from Microsoft offer Telekom Slovenia a cost-effective alternative as IT staff consolidate a new enterprise storage strategy following the merger. “You always have price and performance issues to consider,” says Nemec. “You can have great performance, but up until now it has always cost a lot. We have built the equivalent of two-node Hyper-V clusters and an SAS-attached SAN with tiered storage, and this storage is less than half the cost of an equivalent SAN solution.”

“It used to be that a storage array was as fast as the slowest disk,” adds Koprivnikar. “But with tiering within Storage Spaces, if you chose a combination of SSDs and slower disks that use small amounts of SMB files: this is a very good combination. The overall price is lower than if you buy a whole high-performance array.”

Also, with Windows Server 2012 R2, Telekom Slovenije IT staff can allocate a higher percentage of total physical memory to the CSV cache, which is useful for File and Storage Services storage solutions. Because File and Storage Services clusters are not typically memory constrained, IT staff at Telekom Slovenije can accomplish large performance gains by using the extra memory for the CSV cache. “We plan to use this capability for File and Storage Services clusters hosting audio/video files and for Hyper-V workloads,” says Nemec.

Streamlined Storage Management
Telekom Slovenije expects to simplify storage management thanks to tiering within Storage Spaces, shared VHDX files, and the familiarity that its IT staff has with Windows-based technologies. Shared VHDX files saves a lot of time when building high-availably clusters and storage tiering is simple to implement, with an option to create a storage tier within a simple wizard. When an administrator creates a virtual disk, he can select a check box to enable storage tiering for the virtual disk.

* There is a lot of work to do and every technology that helps to do it is welcome. *

David Koprivnikar
System Engineer Specialist, Telekom Slovenije

“Storage tiering will add agility to our development environment because it’s very easy to set up and configure a high-availability environment, saving a lot of time,” says Koprivnikar. “In the RDP, we saw how easy it was. I just needed to put the storage on the File and Storage Services cluster and after 20 minutes the cluster was operational and the service was running.”

The ease of use will also help IT staff quickly bring the old file servers online, reducing the amount of work caused by the merger. “Reconfiguring our storage service to take advantage of industry-standard hardware that we own is easy. We don’t need any storage engineers to help us. Any system administrator can configure this kind of storage. All it takes is a few clicks and you are done,” says Nemec.

Increased Storage Flexibility
Not every application or system has the same demands for storage. By using tiering within Storage Spaces, Telekom Slovenia can build a flexible storage solution that automatically accommodates different storage requirements within the business—in both physical and virtual environments.

“We can combine slow-spinning disks with SSDs, and Storage Spaces will automatically assign frequently used files to the SSDs and less frequently used, large files to the slow storage,” says Nemec. “We have a lot of developers who are creating applications and manipulating large video files. These are excellent scenarios for storage tiering. Storage Spaces will allocate the large video files that our developers or video editors are working with to less expensive storage disks that still provide enough performance.”

Transform the data center
The hybrid cloud from Microsoft transforms the data center by extending existing investments in skills and technology with public cloud services and a common set of management tools. With an on-premises infrastructure connected to the Windows Azure platform, you can deliver services faster and scale up or down quickly to meet changing needs.

For more information about transforming the data center, go to:

For More Information
For more information about Microsoft products and services, call the Microsoft Sales Information Center at (800) 426-9400. In Canada, call the Microsoft Canada Information Centre at (877) 568-2495. Customers in the United States and Canada who are deaf or hard-of-hearing can reach Microsoft text telephone (TTY/TDD) services at (800) 892-5234. Outside the 50 United States and Canada, please contact your local Microsoft subsidiary. To access information using the World Wide Web, go to:

For more information about Telekom Slovenije products and services, call (01) 234 10 00 or visit the website at:

Solution Overview

Organization Size: 2500 employees

Organization Profile

Based in Ljubljana, Slovenia, Telekom Slovenije is the only integrated telecommunications service provider in Slovenia. It offers new mobile and fixed communications and multimedia contents.

Business Situation

Following a merger with Mobitel, the IT staff needed to consolidate storage solutions, repurpose accumulated file servers, and define a new enterprisewide approach to managing storage more cost-effectively.


Telekom Slovenije will use storage enhancements within the Windows Server 2012 R2 operating system to build file-based storage configurations—an equally robust alternative to the company’s existing storage area network (SAN) solutions.


  • Improved performance at lower cost
  • Streamlined storage management
  • Increased storage flexibility

  • Hewlett Packard DL 360 G7, 24 Gigabytes RAM
  • CISCO UCS B200 M3, 2 x 8 core, 256 Gigabytes RAM

Software and Services
  • Windows Server 2012 R2
  • Microsoft Hyper-V
  • Microsoft Services
  • Microsoft Consulting Services
  • Datacenter

Vertical Industries
  • Telecommunications
  • Communications & Media


Business Need
Cloud & Server Platform

IT Issue
Private Cloud