---
title: "Update an FQDN authentication"
method: PATCH
path: "/fqdn_connections/{fqdn_connection_id}/fqdn_authentication"
tags: ["FQDN Connections"]
---

# Update an FQDN authentication

`PATCH /fqdn_connections/{fqdn_connection_id}/fqdn_authentication`

Updates the FQDN authentication strategy for a specific FQDN connection.

## Path parameters

- `fqdn_connection_id` string, required

## Request body

- UpdateFqdnAuthenticationRequest
  - `user_name` string — The username for authentication.
  - `password` string — The password for authentication.
  - `ip_authentication_method` 'token' | 'p-charge-info' — The IP authentication method.
  - `fqdn_outbound_authentication` 'ip-authentication' | 'credential-authentication' — The outbound authentication type.
  - `webhook_url` string, uri — The webhook URL for authentication events.
  - `failover_url` string, uri — The failover webhook URL.
  - `txt_name` string — The TXT record name for Microsoft Teams SBC DNS verification.
  - `txt_value` string — The TXT record value for Microsoft Teams SBC DNS verification.
  - `txt_ttl` integer — The TTL for the TXT record.

## Response `200`

Successful response with the updated FQDN authentication.

- object
  - `data` FqdnAuthentication
    - `id` string — Identifies the resource.
    - `record_type` string — Identifies the type of the resource.
    - `connection_id` string — The ID of the FQDN connection this authentication strategy belongs to.
    - `user_name` string — The username for authentication.
    - `password` string — The password for authentication. For primary accounts created on or after September 8, 2026, this password is returned as `********`. The password is returned in full on create, and on update only when that update changed the password. Accounts created before September 8, 2026 are unaffected.
    - `ip_authentication_method` 'token' | 'p-charge-info' — The IP authentication method.
    - `fqdn_outbound_authentication` 'ip-authentication' | 'credential-authentication' — The outbound authentication type.
    - `webhook_url` string, uri — The webhook URL for authentication events.
    - `failover_url` string, uri — The failover webhook URL.
    - `microsoft_teams_sbc` boolean — Whether the connection is a Microsoft Teams SBC.
    - `txt_name` string — The TXT record name for Microsoft Teams SBC DNS verification.
    - `txt_value` string — The TXT record value for Microsoft Teams SBC DNS verification.
    - `txt_ttl` integer — The TTL for the TXT record.

## Other responses

- `401` — Unauthorized
- `403` — The user doesn't have the required permissions to perform the requested action.
- `404` — The requested resource doesn't exist.
- `409` — Conflict. Another update to this connection is still in progress. Wait and retry the request later.
- `422` — The request was well-formed but was unable to be followed due to semantic errors.

## Changes

> 93 revisions in range; 1 not diffed.

- **2026-08-17** `1571b0380bd7` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/team-telnyx/apis/telnyx-api-2/changes/fqdn_connections/:fqdn_connection_id/fqdn_authentication/patch.md)

---

[API](https://skmtc.dev/team-telnyx/apis/telnyx-api-2.md) · [All operations](https://skmtc.dev/team-telnyx/apis/telnyx-api-2/llms.txt) · [OpenAPI document](https://skmtc.dev/team-telnyx/apis/telnyx-api-2/revisions/88481995b4ca?raw)