This guide explains how to perform an online speed test from the command line (iPerf CLI) between your computer and your Synology NAS. These tests can help you evaluate the download and upload speeds of your Internet connection to and from your NAS.

Speedtest tool configuration

To install the SynoCli Monitor Tools package:

1. From the DSM interface, go to the Package Center.
2. Click the Settings button in the taskbar, then go to the Package Source tab.
3. Click the Add button.
4. Fill in the fields as follows:
   • Name: SynoCommunity
   • Location: https://packages.synocommunity.com/
5. Confirm both windows by clicking OK.
6. A new tab titled Community will appear in the left-hand menu.
7. Select it, then install the SynoCli Monitor Tools package.

Enabling the SSH connection

To enable the SSH service:

1. In the DSM interface, open the Control Panel.
2. Click on the Terminal & SNMP tab in the left-hand menu.
3. Check the Enable SSH service box.
4. Click Apply to confirm.
   • If you no longer need the SSH connection after the test, you can uncheck this box to disable the service.

Starting the iPerf server

To connect to the NAS via SSH, from a Terminal application (command-line interface, CLI / Command Line Interface) on your device:

1. Run the following command:

   ssh nom_utilisateur_dsm@ip_du_synology

2. Enter the password for your DSM account, then press Enter.

3. Once connected via SSH, start the iPerf server with the following command:

   iperf3 -s

Starting the speed test

To download and run the iPerf3 client:

1. Download the iPerf3 executable for your operating system from the official site.
2. Open a new console.
3. Navigate to the folder where the iPerf3 executable is located.

4. Run the following command:

   iperf3 -c ip_du_synology

5. The test results will appear after a few seconds. You will then be able to view the upload and download bandwidth between your computer and your Synology NAS.