---
title: "Run connection tests from the terminal"
description: "Start connection tests on the terminal and learn how to interpret the results."
url: "https://docs.adyen.com/point-of-sale/pos-troubleshooting/connection-tests"
source_url: "https://docs.adyen.com/point-of-sale/pos-troubleshooting/connection-tests.md"
canonical: "https://docs.adyen.com/point-of-sale/pos-troubleshooting/connection-tests"
last_modified: "2020-10-09T12:30:00+02:00"
language: "en"
---

# Run connection tests from the terminal

Start connection tests on the terminal and learn how to interpret the results.

[View source](/point-of-sale/pos-troubleshooting/connection-tests.md)

On the payment terminal, you can run tests to verify the connection:

* Between the terminal and the Adyen payments platform.
* Between the terminal and the Adyen Terminal API.
* Between the terminal and various endpoints, for example for receiving updates.

The next sections describe:

* How to run the connection tests.
* What it means when a connection test fails.

## Requirements

Before you begin, take into account the following requirements.

| Requirement          | Description                                                                                                        |
| -------------------- | ------------------------------------------------------------------------------------------------------------------ |
| **Integration type** | * A Terminal API integration using payment terminals integrated with a POS system.
* Standalone payment terminals. |
| **Hardware**         | All non-legacy payment terminals.                                                                                  |
| **Limitations**      | Some tests apply only to cloud communications or only to local communications.                                     |

## Run diagnostic connection tests from a terminal

1. Check the icons in the top row of the terminal display. If an expected icon is missing, that is the first indication of what is wrong.

   * If the terminal uses a Wi-Fi connection, you should see the Wi-Fi symbol.

   * If you have a Terminal API integration using cloud communications, you should see a cloud symbol.

2. Go to **Settings** and select **Diagnostics**.

   * On *non-Android terminals* that use the [old menu structure](/point-of-sale/menu-access#old-menu-structure), go to the Admin menu and select **Network** > **Diagnostics**.

   * On an *Android* terminal, go to **Settings** and select **Diagnostics**.

3. Under **Diagnostics**, select **PSP connection** and check the result. Refer to [PSP connection test](#psp-connection-test).

4. Go back to **Diagnostics**, select **Terminal API** and check the result. Refer to [Terminal API test](#terminal-api-test) and [Local communications TLS test](#local-communications-tls).

5. Go back to **Diagnostics** and select **Endpoints**. The terminal runs tests on four URLs and shows the results. Refer to [Endpoints test](#endpoints-test).

On a *non-Android* terminal that uses the [old menu structure](/point-of-sale/menu-access#old-menu-structure), when tests pass the terminal shows a green check mark ![-white\_check\_mark-](/user/data/smileys/emoji/white_check_mark.png "-white_check_mark-") for all steps in a test. If a test fails, it is marked with red cross ![-x-](/user/data/smileys/emoji/x.png "-x-"), and all steps are also marked as failed with a red cross ![-x-](/user/data/smileys/emoji/x.png "-x-").\
On an *Android* terminal, when tests pass the terminal shows **Successful**. If you tap **Successful**, all steps show a green check mark ![-white\_check\_mark-](/user/data/smileys/emoji/white_check_mark.png "-white_check_mark-"). If a test fails, the terminal shows **Failed**, and all steps when you tap **Failed** are also marked as failed with a red cross ![-x-](/user/data/smileys/emoji/x.png "-x-").

The next sections explain what it means when a test step fails.

## PSP connection test

The **PSP connection** test verifies the connection to the Adyen payments platform. The test checks the DNS resolution, firewalls, routing, and TLS negotiations.

If a test step fails, all steps after that are also marked as failed with a red cross ![-x-](/user/data/smileys/emoji/x.png "-x-").

| Test step           | Result                                       | Description                                                                                                                                                                                                                                                                                                                                                                |
| ------------------- | -------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Looking up host** | ![-x-](/user/data/smileys/emoji/x.png "-x-") | There is a DNS problem. The terminal is not able to resolve the Adyen domains. Contact your company's network or IT team.                                                                                                                                                                                                                                                  |
| **Connecting**      | ![-x-](/user/data/smileys/emoji/x.png "-x-") | Something in the network is preventing the terminal from connecting. There can be several causes:- A problem with your router.
- The internet connection is down.Contact your company's network or IT team.                                                                                                                                                                |
| **Negotiating**     | ![-x-](/user/data/smileys/emoji/x.png "-x-") | This step checks the security of the connection. If it fails, this can indicate:- Your security gateway is inspecting the TLS session. If that is the case, wait for the inspection to finish. We recommend bypassing any inspections of Adyen domains.
- Some other problem.**Contact Adyen immediately.**                                                                |
| **Writing data**    | ![-x-](/user/data/smileys/emoji/x.png "-x-") | Traffic from the terminal is blocked. There is a problem with the settings of your router or firewall. Contact your company's network or IT team.                                                                                                                                                                                                                          |
| **Receiving data**  | ![-x-](/user/data/smileys/emoji/x.png "-x-") | Traffic to the terminal is blocked. There is a problem with the settings of your router or firewall. If you connected the terminal for the first time and the overall result of the PSP connection test is **No Error**, the terminal is successfully connected and you can ignore the red cross for Receiving data. Otherwise, contact your company's network or IT team. |

## Terminal API test

The **Terminal API** test verifies the API connection and the cloud WebSocket connection. For integrated terminals using local communications, you can ignore the WebSocket test results.

If a test step fails, all steps after that are also marked as failed with a red cross ![-x-](/user/data/smileys/emoji/x.png "-x-").

| Test step                | Result                                       | Description                                                                                                                                                           |
| ------------------------ | -------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **API enabled**          | ![-x-](/user/data/smileys/emoji/x.png "-x-") | To solve this issue, enable Terminal API in your [Customer Area](https://ca-live.adyen.com/) under **In-person payments** > **Terminal settings** > **Integrations**. |
| **WebSocket enabled**    | ![-x-](/user/data/smileys/emoji/x.png "-x-") | To solve this issue, enable WebSockets in your [Customer Area](https://ca-test.adyen.com/) under **In-person payments** > **Terminal settings** > **Integrations**.   |
| **WebSocket connection** | ![-x-](/user/data/smileys/emoji/x.png "-x-") | The cloud connection with our Terminal API fails.                                                                                                                     |

## Local communications TLS test

The **Terminal API** test also returns information about the Transport Layer Security (TLS) used in your [local communications](/point-of-sale/design-your-integration/choose-your-architecture/local) integration.

For integrated terminals using [cloud communications](/point-of-sale/design-your-integration/choose-your-architecture/) and for standalone terminals, these tests are not applicable.

| Test step       | Description                                                                                             |
| --------------- | ------------------------------------------------------------------------------------------------------- |
| **TLS version** | Transport Layer Security (TLS) version used in the communication between your POS app and the terminal. |
| **Cipher**      | The cipher used to encrypt and decrypt messages.                                                        |
| **URL**         | The address that your POS app connects to. Depends on your integration.                                 |

## Endpoints test

The **Endpoints** test verifies whether the terminal is able to connect with several URLs:

* **Sync URL**, which is used for refunds and cancellations.
* **Config URL**, where the terminal retrieves its configuration.
* **PAL URL**, where the terminal sends requests.
* **Firmware URL**, where the terminal retrieves the latest software release.

The test also shows the [Maximum Transmission Unit (MTU) value](/point-of-sale/design-your-integration/network-and-connectivity/networking-issues#avoid-mtu-issues) that the terminal is using.

For each of the above URLs the terminal carries out the following test steps:

If a test step fails, all steps after that are also marked as failed with a red cross ![-x-](/user/data/smileys/emoji/x.png "-x-").

| Test step           | Result                                       | Description                                                                                                                                                                                      |
| ------------------- | -------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **Looking up host** | ![-x-](/user/data/smileys/emoji/x.png "-x-") | There is a DNS problem. Contact your company's network or IT team.                                                                                                                               |
| **Connecting**      | ![-x-](/user/data/smileys/emoji/x.png "-x-") | There can be several causes:- A problem with your router.
- Our server is down.
- The internet connection is down. Contact your company's network or IT team.                                    |
| **Negotiating**     | ![-x-](/user/data/smileys/emoji/x.png "-x-") | This step checks the security of the connection. If it fails, this can indicate that we have updated our certificates, or that you have fallen victim to hacking. **Contact Adyen immediately.** |
| **Writing data**    | ![-x-](/user/data/smileys/emoji/x.png "-x-") | There is a problem with the settings of your router or firewall. Contact your company's network or IT team.                                                                                      |
| **Receiving data**  | ![-x-](/user/data/smileys/emoji/x.png "-x-") | There is a problem with the settings of your router or firewall. Contact your company's network or IT team.                                                                                      |

## See also

* [Make a diagnosis request](/point-of-sale/diagnostics/request-diagnosis)
* [Network and connectivity](/point-of-sale/design-your-integration/network-and-connectivity)
* [Know when certificates expire](/point-of-sale/design-your-integration/network-and-connectivity/wi-fi-profiles#know-when-certificates-expire)
