---
title: "system.opcua.addConnection"
description: "Adds a new OPC UA connection."
---

# system.opcua.addConnection

> Adds a new OPC UA connection.

This function is used in **Python Scripting**.

## Description
## Client Permission Restrictions
This scripting function has no [Client Permission](../../../ignition-modules/vision/vision-project-properties/vision-project-properties.md#vision-permissions-properties) restrictions.

## Syntax
`system.opcua.addConnection(name, description, discoveryUrl, endpointUrl, securityPolicy, securityMode, settings)`

### Parameters
Type | Parameter | Description 
------- | ------- | ------
String| `name` | Name to assign to the new connection. 
String| `description` | Description assigned to the new OPC UA connection. 
String| `discoveryUrl` | Endpoint URL to use for discovery services.
String| `endpointUrl`  | Endpoint URL to use for session services. 
String| `securityPolicy` | The name of the SecurityPolicy to use. See the Security Policy table below for possible values. 
String| `securityMode` | The name of the MessageSecurityMode to use. See the Message Security Mode table below for possible values.
Dictionary[String, Any]| `settings` | A dictionary of additional settings to apply to the connection. See the Settings table for a table of possible keys.  

### Returns
Nothing
### Scope
Gateway, Perspective Session

### Security Policy
Below is a listing of supported values for the securityPolicy argument:

* None
* Basic128Rsa15
* Basic256
* Basic256Sha256
* Aes128_Sha256_RsaOaep
* Aes256_Sha256_RsaPss

### Message Security Mode
Below is a listing of supported values for the messageSecurityMode argument:

* None
* Sign
* SignAndEncrypt

### Settings 
Below is a listing of supported values for the settings argument: 

| Key                          | Data Type |
| ---------------------------- | --------- |
| ENABLED                      | Boolean   |
| DISCOVERYURL                 | String    |
| ENDPOINTURL                  | String    |
| SECURITYPOLICY               | String    |
| SECURITYMODE                 | String    |
| USERNAME                     | String    |
| PASSWORD                     | String    |
| HOSTOVERRIDE                 | String    |
| CONNECTTIMEOUT               | Integer   |
| ACKNOWLEDGETIMEOUT           | Integer   |
| REQUESTTIMEOUT               | Integer   |
| SESSIONTIMEOUT               | Integer   |
| MAXPEROPERATION              | Integer   |
| MAXREFERENCESPERNODE         | Integer   |
| MAXPENDINGPUBLISHREQUESTS    | Integer   |
| MAXNOTIFICATIONSPERPUBLISH   | Integer   |
| MAXMESSAGESIZE               | Integer   |
| MAXARRAYLENGTH               | Integer   |
| MAXSTRINGLENGTH              | Integer   |
| TYPEDICTIONARYFRAGMENTSIZE   | Integer   |
| KEEPALIVEFAILURESALLOWED     | Integer   |
| KEEPALIVEINTERVAL            | Integer   |
| KEEPALIVETIMEOUT             | Integer   |
| BROWSEORIGIN                 | String    |
| CERTIFICATEVALIDATIONENABLED | Boolean   |
| KEYSTOREALIAS                | String    |
| KEYSTOREALIASPASSWORD        | String    |
| FAILOVERENABLED              | Boolean   |
| FAILOVERTHRESHOLD            | Integer   |
| FAILOVERDISCOVERYURL         | String    |
| FAILOVERENDPOINTURL          | String    |
| FAILOVERHOSTOVERRIDE         | String    |

## Code Examples
```python title="Example #1"
# The following could be used to connect to Ignition's OPC UA server.
system.opcua.addConnection(
    "test",
    "test desc",
    "opc.tcp://localhost:62541/discovery",
    "opc.tcp://localhost:62541",
    "Basic256Sha256",
    "SignAndEncrypt",
    {
    "username":"opcuauser",
    "password":"password"
    }
)
```