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File Service
Updated 20 Oct 2026

File Service

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This section configures file storage.

Contour

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Here you specify the IP addresses of the internal contour of the corporate data transmission network (CDTN) and file permissions for users of this contour.

How to Configure Networks Recognized as CDTN Perimeter?

Specify corporate networks/IPs considered as secure corporate network perimeter — corporate data transmission network (CDTN) perimeter (“contour”). If necessary, requests from user client devices are checked to determine whether they belong to the contour.

  1. Add subnet IP addresses with masks using /, separating values with commas. Example: 192.168.0.0/24, 10.129.0.0/16.
    You can also specify an exact external provider IP with /32 mask: this IP will also be considered part of the perimeter. Do this only for testing. Example: 55.66.77.88/32.
    You can find your provider-assigned IP address on these sites:
  2. Optionally, set file reading and sending parameters relative to the contour. They combine with the role model restrictions in effect.
  3. Check the Enabled box and click Save.

How Is Role Model Related to CDTN Perimeter?

The connection is as follows: the role model operation depends on the contour settings.

CDTN Perimeter Parameters

Parameter Description
Corporate users can send Defines who a CDTN user can send files to:
  • any — any user in the federation, regardless of the server they are on. Only a CDTN user can open the file. Files can be sent to open chats, channels, and chats with end-to-end encryption disabled.
  • corporate — a user on any corporate server of any organization except RTS. Only a CDTN user can open the file. Files can be sent to open chats, channels, and chats with end-to-end encryption disabled.
  • trust — a user on a server with which a trusted connection is established. Only a CDTN user can open the file. Files cannot be sent to open chats, channels, or chats with end-to-end encryption disabled.
  • local — a user on the same server as the sender. Only a CDTN user can open the file. Files cannot be sent to open chats, channels, or chats with end-to-end encryption disabled.
Corporate users can read Defines who a CDTN user can receive and open files from:
  • any — from any user, regardless of the server. The sender’s and recipient’s contours do not affect file access.
  • corporate — from a user on a corporate server. The sender’s and recipient’s contours do not affect file access.
  • trust — from a user on a server with which a trusted connection is established.
  • local — from a user on the same server as the recipient.
  • contour — from a user on the same contour as the recipient.
Corporate files can read Defines who can view files sent from the CDTN:
  • any — any user from any server. The sender’s and recipient’s contours do not affect file access.
  • corporate — a corporate user from a sender on a corporate server. The sender’s and recipient’s contours do not affect file access.
  • trust — a user on a corporate server connected via a trusted connection to the sender’s server. The sender’s and recipient’s contours do not affect file access.
  • local — a user on the same corporate server as the sender. The sender’s and recipient’s contours do not affect file access.
  • contour — a CDTN user on the same contour as the sender.

CDTN Contour and End-to-End Encryption

When selecting the Trust or Local parameters, users within the CDTN cannot send files to open chats or chats with end-to-end encryption disabled. When selecting Any or Corporate, sending is possible (starting from server software version 2.9).

File Service Retention

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Here you configure automatic deletion of files from the server. The period is set in days separately for each category: Documents, Media, Voice, Voex recordings, Voex transcribing, Voex logs, Contacts, Links, Poll report. If the field is empty, files in this category are not deleted.

Files Sent from Another Server

The File Retention feature enabled on the server also applies to files sent by users from other servers. Chats and files are uploaded from there to the current server, and after the specified time, automatic deletion is triggered for them.

Cleaning Files by Date and Size

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Since version 3.73 in the File Service section, an administrator can delete from the server, as a one-time action, files uploaded during the selected period, files of the selected size, or files that meet both conditions. Use it when the disk runs out of space before files are removed by automatic retention-based deletion.

  1. In the Clear files by selected filters block, select a date range, file size, or both parameters.
  2. Click Clear.
  3. Check the conditions in the confirmation window and click Delete.

Under the button, the panel shows the date and status of the last cleanup: Success, No files found, or Error. In the Last cleanup filters row, the selected dates and size are shown.

Proxying

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Static proxying settings for public clients. With them, the file can be downloaded through File Service instead of a link with a redirect to S3.

Watermark Configuration

When a user saves or forwards images and video from a mobile device, a semi-transparent watermark with information about the user, time, and device is applied to them. The same information is written to the file metadata. The watermark helps to find the source of a data leak.

The watermark is added by the iOS and Android apps. The web and desktop apps do not add it. The server setting of the user who saves the file applies. By default, the watermark is disabled. Introduced in server software version 3.69 and mobile clients iOS/Android 3.70.

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