Santa's little Digital Engineer helpers

The Christmas online shopping season started again with Black Friday offers at the end of November. During the Christmas season, more than one million parcels a week pass through Posti's sorting centers. The popularity of online shopping has grown year by year, and the COVID-19 epidemic has further increased e-shopping. In addition to parcels, Posti will also deliver almost 30 million Christmas cards this Christmas. 

The Christmas season brings work not only to Posti's employees but also to information systems as customers diligently monitor the flow of parcels and packages through Posti's electronic service channels. Even Posti's internal services run at full capacity by automatically reading the address information of Christmas cards and directing items to their recipients. 

Posti prepares for the Christmas season and the extra load it causes well in advance throughout the year, and Posti's IT department eats their first Christmas cookies not long after the end of the summer holidays. System congestion is managed using, among other things, modern cloud services, and many of Posti's electronic services are produced in Microsoft Azure or Amazon Web Services environments. 

With the help of cloud services, the capacity of the systems can be easily increased when needed. Server capacity no longer needs to be scaled up for the Christmas peak season but will automatically increase and decrease as needed. Although some of Posti's services are still produced from traditional data centers, almost all new services are designed to be suitable for a cloud environment from the outset. 

A key part of Posti’s cloud architecture is the use of Docker containers. Docker allows applications and services to be packaged into platform-independent containers. The container provides the application with a constant running environment that can be moved from the developer’s machine to the cloud to run without the application inside noticing the difference. The containers are like small and easy-to-move virtual servers.

 In addition to mobility, the containers are often also unchanged. As the application evolves, an update will be released as a new version of the container, leaving the old one intact. The cloud service will ensure that the new version replaces all old running containers without downtime. If the new version does not work as expected or has an error, it is easy to revert to the previous version. 

A good feature also for the Christmas season is that containers can be easily cloned. The cloud service constantly monitors the load on the containers. If the number of users increases, new clones are automatically launched to share the increased need. As the load peak decreases, the extra containers are taken out of service. Flexibility brings tangible benefits as the increased number of visitors during the Christmas period is very unevenly distributed at different times of the day. Individual congestion peaks occur, for example, both before and after the start of workdays.

While cloud services can scale up virtually indefinitely, the limitations of the physical world may still apply. Parcel lockers can only hold a limited number of parcels at a time, so please pick up the shipment you ordered as soon as possible. This allows your neighbours to receive their parcels as close to home as possible.

The Digital Engineers wish everyone a great and package-rich Christmas!

By the way, did you know that Santa's official address is "Tähtikuja 1, 96930 ARCTIC CIRCLE, FINLAND" and that Posti's sorting machines have their own special button for Santa?