UK energy supplier provides flexible and reliable performance to power users with XenDesktop

Calor Gas Ltd., founded in 1935, is a household name in the UK as a supplier of liquefied petroleum gas (LPG) to domestic and business customers. LPG provides “off-grid energy” for rural homes, poultry farms, plant nurseries and a wide range of other situations where either portability is vital or the premises are not connected to the mains gas supply. Headquartered in Warwick, in the heart of England, Calor supplies its retail and wholesale customers through a network of depots across the UK.

The challenge: providing a consistent user experience to both regular and power users

Calor operated a mixed IT environment. Since 2000, the firm has delivered a hosted shared virtual desktop, using XenApp, to around 900 corporate users. However, it also had three sets of special use-cases where it used other solutions.

Firstly, Calor had a number of power users – including software developers and business analysts – who required dedicated computing resources for tasks such as compiling code or running large Excel spreadsheets. The IT department had developed their own, ad hoc, VDI solution to meet these needs. However, as Andy Browne, manager of Calor’s Technical Infrastructure Group, explains, “The solution wasn’t isolated from our production server workloads and, as a result, we were having severe capacity and performance problems that affected all users.” When power users were running particularly memory- or storage-intensive tasks, all users would suffer poorer performance.

Secondly, in addition to using in-house developers, Calor increasingly outsourced development work. These third-party developers required remote access to the firm’s test and development systems to compile code and de-bug software. VPNs between the developer and Calor sites provided access, but this solution was inflexible and difficult to scale. Andy explains, “About half of our development work is now done off-site, but we are still predominantly an on-premises business with regards to our architecture.”

The third use-case involved a business-critical application used by Calor’s depots to schedule deliveries of LPG. This application, which coordinated customer orders with supplies in the depot and Calor’s main storage facilities, was particularly data-heavy and ran locally on individual PCs. It was becoming difficult to maintain as data volumes increased and the PC hardware got older. The software failed once or twice a year, delaying affected depots’ scheduling workloads by around four hours and causing knock-on problems for their customers. To minimize downtime, members of the IT team had to fix the local problem as quickly as possible, travelling from Warwick to the affected depot and often re-creating damaged data files.

The solution: delivering a secure virtual desktop with dedicated computing resources

Andy and his team needed a cost-effective solution that would supply the storage capacity and performance their power users needed without compromising system performance and availability for everyone else. Andy also wanted a secure solution for providing remote access for developers. He hoped that the high-performance solution required by power users could also be used to bring Calor’s delivery-scheduling app into the data centre so that it could be centrally managed with Calor’s other apps.

Andy’s preference was to run a separate environment for the three special use-cases to ensure that regular users were not adversely affected by demands on resources. Having experienced the challenges of managing an ad hoc VDI solution, he was keen to find a single, “productised” solution that would be easy to support.

Calor already used XenApp with the Atlantis ILIO storage management solution. Working with Atlantis, Andy and his team designed a new architecture built on two Atlantis HyperScale CX-12 devices. These units provide a high-performance, hyper-converged solution that combines compute power, All-Flash storage and networking in a single appliance. One appliance was used to serve the existing XenApp hosted shared desktop, while the other supported a new XenDesktop environment for the special use-cases that Calor had identified. While all users will access a familiar Windows 7 desktop of productivity applications, XenDesktop users will also have the specific applications they require for their roles. Whether Excel for analysts, development software for developers or the scheduling app for depots, applications will be delivered to users based on their particular profile. XenDesktop will allocate dedicated computing resources to each power user, ensuring each person has the storage and processing power required for the job in hand.

Currently, the XenDesktop solution is being rolled out to the first two use-cases (power users and remote developers). Once the solution is fully deployed, all applications will be managed and delivered from the data centre. Installation, upgrades and maintenance will be performed centrally, helping to increase IT efficiency and minimize disruption to users or customers. Bringing the delivery scheduling app into the data centre will avoid the need to travel to depots to fix issues with locally installed software. The application’s intensive data processing will take place in the data centre, and depot staff will access it through a virtual desktop delivered to existing PCs or replacement thin-client terminals.

Key benefit: delivering a consistent experience and performance to all users

With Citrix virtualisation, remote and mobile users can access their desktop over the network on any device running the Citrix Receiver client – a thin-client terminal in the office, a personal laptop at home or a tablet device in the field – and enjoy a consistent experience.

XenDesktop ensures that power users and remote developers have the dedicated computing resources they require without impacting performance for other users. Dedicated resources, combined with the storage-performance benefits of the HyperScale appliance, mean that Andy’s team can soon bring the data-heavy delivery application into the data centre, too. Efficient, centralised management will improve the application’s reliability, helping depots ensure that customer deliveries remain on schedule.

External developers can now securely access Calor’s test and development environment from their local machines by running Citrix Receiver. Access is controlled by HyperScale at a granular, user-profile level so that developers (and everyone else) are given access only to the applications and information required by their roles.

Andy explains, “Citrix and Atlantis are a really good combination. The Atlantis HyperScale system gives us a consistently high-performance end-user experience, whatever the total workload on the system. XenDesktop delivers a seamless desktop experience, ensuring that internal and external power users have the appropriate resources for whatever they are doing, on whatever device they are using. Together, the Citrix and Atlantis solution gives power users a good level of performance, reliability and resilience. It gives users the right tools and the right resources to deliver what they need to do, when they need to do it. Where it’s already been deployed, it’s something our end-users rely on. They just expect it.”

Key benefit: simplifying IT management and reducing workload

Managing the entire XenDesktop environment from the data centre will make the job much simpler for Andy’s team. “Having everything in the data centre and backed up means we can manage our environment more efficiently, without having to travel to local depots to fix problems,” he explains.

Overall, Andy summarises, “Citrix gives us simplicity of delivery and so many different options. The solution is straightforward and almost self-managing, so we spend less timing administering the whole environment. Over the years, Citrix virtualisation has saved us an absolute fortune, and it’s enabled us to do some interesting and innovative things.”

Looking Ahead

Andy and his team are currently rolling out the XenDesktop environment. Looking further ahead, Calor is considering issuing field workers with Apple iPad tablets to access their Citrix desktop, in place of their current laptops.

“Citrix always seems to develop and move with the times and it’s been such a useful toolkit to have. It’s enhanced our capability to deliver applications in interesting and different new ways, such as delivering legacy applications to mobile devices to keep pace with the mobile revolution,” says Andy.

Citrix gives us simplicity of delivery and so many different options. The solution is straightforward and self-managing, so we spend less timing managing the whole environment. Over the years, Citrix virtualisation has saved us an absolute fortune, and it’s enabled us to do some interesting and innovative things.
- Andy Browne

Manager, Technical Infrastructure Group

Calor Gas Ltd.

About Citrix

Citrix (NASDAQ:CTXS) aims to power a world where people, organizations and things are securely connected and accessible to make the extraordinary possible. Its technology makes the world’s apps and data secure and easy to access, empowering people to work anywhere and at any time. Citrix provides a complete and integrated portfolio of Workspace-as-a-Service, application delivery, virtualization, mobility, network delivery and file sharing solutions that enables IT to ensure critical systems are securely available to users via the cloud or on-premise and across any device or platform. With annual revenue in 2015 of $3.28 billion, Citrix solutions are in use by more than 400,000 organizations and over 100 million users globally. Learn more at

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Citrix always seems to develop and move with the times and it’s been such a useful toolkit to have. It’s enhanced our capability to deliver applications in interesting and different new ways, particularly with the mobile revolution. It’s enabled us to deliver legacy applications to mobile devices.
- Andy Browne

Manager, Technical Infrastructure Group

Calor Gas Ltd.

Key benefits

  • Delivers consistent experience and performance to all users
  • Simplifies IT management and reduces workload

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