Russian Airline at home in the cloud

Moving to the cloud

While choosing the provider of the cloud system, S7 had strict requirements, including more than 99.9 % uptime.

“Under the classic Uptime Institute system, 99.9% means just more than eight hours of downtime a year,” said Yegor Bayandin, director for technical support at S7 t-Retail.

“Theoretically, those hours could be in a row and during the same day, which was unacceptable for us, and that issue was immediately discussed with a potential cloud provider.”

Eventually, S7 selected IT-Grad, a company with offices in Moscow, St Petersburg and Almaty. The airline quickly saw the advantages of moving to the cloud.

“What we like most is the feel of complete control over virtual machines,” said Bayandin. “We can distribute available resources the way we like, depending on load peaks and requests from our developers.

“Previously, distribution of resources inevitably led to the purchase of hardware and long readjustment of the equipment.

“Virtualisation solved some of those problems, but eventually we were still limited by the capabilities of the hardware. Now we have a virtual datacentre, we don’t really have to think much about equipment.”

The process of switching to the cloud was gradual. Initially, just 1% of production load was in cloud, with the rest allocated to testing new services and changes.

“We make division between our datacentre and the cloud at the level of specific information systems,” said Bayandin. “That means a service either has been completely moved to the cloud, or is operated by S7’s datacentre.

Pros and cons

S7 hardly sees any disadvantages in the use of the cloud infrastructure. “It’s hard to find negatives, in principle,” said Bayandin. “It’s probably just that we haven’t found the most suitable scheme for working with the pay-as-you-go model.

“There are undeniable advantages of using the allocated model, but the technical specifics of how VMware works with memory don’t always allow us to profit from those advantages.”

Initially, the company experimented with both models for cloud payment. “[The pay-as-you-go model] looked more interesting as accurate forecasts of peak loads were unlikely,” said Bayandin, however the company stuck to the model that allocated resources.

As for benefits of using the cloud infrastructure, S7 discovered several. “[We got] flexibility when it comes to distribution of resources,” Bayandin said. “If you have 100 virtual central processing units [CPUs] and two dozen TBs of memory, you can use all that in the way you like and on any virtual machine. You don’t have to select memory for specific hardware or re-distribute hardware between virtual hosts.”

Another major advantage, according to Bayandin, is a drastic increase in the roll-out speed of virtual machines, saying it takes two to three hours from start to finish, as opposed to a few days.

There is also no need to deal with purchases and upgrade of equipment. “This is an important thing for us, as the process of ordering needs a large number of approvals,” said Bayandin.

Fine-tuning infrastructure

Finally, the use of the cloud has allowed the company to avoid the majority of errors during tuning of the infrastructure. “As the cloud provider has staff who are experts in specific products, such as VMware, many issues and peculiarities of tuning virtual systems were solved a long time ago,” he said.

“Overall, we have a quite positive experience of working in the cloud environment. We will certainly develop this project further,” he added.

Stanislav Mril, commercial director at IT-Grad, said: “S7 plans to eventually completely move to the cloud infrastructure. At the moment, we’re hosting its development and test environment on our cloud. In 2017, some production is to move to the cloud, bringing about an increase in customer traffic.”