When there is an issue with a remote terminal, it is necessary to determine the problem. For this to happen, it is required to know what the settings of the terminal are and what steps preceded the malfunction. After that, remote debugging must be performed. To analyze and locate the problem remotely, activity and diagnostics logs are used.
Activity logs store the information of all the activities of the terminal and record all operations performed by it.
Diagnostics logs store all characteristics data (memory, number of hard drives, peripherals’ performance, etc.), applications uploaded to the terminal, and data regarding the physical condition of the terminal.
The TMS allows users to review all operations performed by the terminal before the failure occurred.

When the recovery process is activated, a terminal is rolled back to the most stable version (the last version functioning trouble-free for an extended period of time in the production environment). This version is supposed to facilitate the proper operation of the terminal and potentially download new updates. Typically, it is called a base version. The base version of the application is uploaded to the new (factory) terminals by the fulfillment center. After that, in cases of recovered terminals, new updates can be installed based on this version.

To perform a terminal update, the required files are uploaded to the terminal. For security reasons, and in order to unify and organize the uploading process of these files remotely, files must be uploaded from a single location called a repository. A repository is a vault for files that are uploaded to the terminal during the updates. Terminal update files are downloaded from a local computer and, subsequently, to the repository. From the repository, the files are uploaded to the terminals via TMS API.

There is a need to update terminals that belong to a particular group. This is done to avoid cases where a malfunction occurs on numerous terminals, which, subsequently, may necessitate costly repairs. For example, an update is issued for the update profile used for mobile and desktop terminals. This update is released to fix a bug present in the mobile terminals only. In this particular case, all mobile terminals (a problem group) are segregated into a separate sub-group (a segment) within the update profile. This sub-group of terminals is uploaded with specific versions of the update. Thus, the segment allows for the updating of only those terminals belonging to it.

During the terminal update, it is complicated and inconvenient to integrate the settings of each particular terminal. To optimize this process, the terminals are divided into groups with similar/repeated characteristics. With regard to these characteristics, a corresponding terminal update of the application is uploaded. The update for a particular group of terminals is required for:

• terminals of the same model or manufacturer (Ingenico, Verifone);
• a specific terminal application version that differs dramatically from the others;
• merchants belonging to the same business type but differing dramatically from the others.

To update terminals of the same group, an update profile is used. The profile is a series of settings required for a particular group of terminals. Based on these settings, the terminal application is uploaded to the terminal. The profile defines which version (in what form and with what parameters) is going to be installed on the particular group of terminals. In other words, the update profile allows the user to combine the settings required for a particular group of terminals and manage multiple processes related to the terminal update.

Not all terminals should be updated simultaneously because there is a chance that the latest version of an update may contain bugs or shortcomings, which can negatively impact terminal efficiency. Additional reasons for not updating all terminals at once include various terminals having different versions of updates already installed, some terminals being deactivated for a period of time, or having been in transit. For those reasons, different terminals may have various builds of the application installed. To understand which functionality a particular terminal possesses, it is necessary to track which version is installed on each terminal. To help simplify this process, each application build is assigned its version (code) - update version.