| # Troubleshooting |
|
|
| ## Azure Authentication |
|
|
| ### `DefaultAzureCredential` fails on first run (IMDS timeout) |
|
|
| **Symptom:** The first pipeline run fails with a long error listing all attempted credentials: |
| ``` |
| DefaultAzureCredential failed to retrieve a token from the included credentials. |
| Attempted credentials: |
| ManagedIdentityCredential: ManagedIdentityCredential authentication unavailable, no response from the IMDS endpoint. |
| AzureCliCredential: Failed to invoke the Azure CLI |
| ... |
| ``` |
|
|
| **Cause:** `DefaultAzureCredential` tries `ManagedIdentityCredential` early in its chain. On a local dev machine, this attempts to contact the IMDS endpoint which doesn't exist locally, so it blocks until the network timeout (~5-10s). This can exhaust the overall credential chain timeout or cause cascading failures before `AzureCliCredential` gets a chance to run. |
|
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| This is expected behavior — `DefaultAzureCredential` probes the IMDS endpoint to detect the hosting environment, and the timeout is unavoidable on local machines unless the credential chain is configured to skip it. |
|
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| **Fix:** Set the `AZURE_TOKEN_CREDENTIALS` environment variable to `dev` to exclude deployed-service credentials (e.g. `ManagedIdentityCredential`, `WorkloadIdentityCredential`) from the chain, so `DefaultAzureCredential` skips straight to developer-tool credentials like `AzureCliCredential`: |
|
|
| ```bash |
| # PowerShell |
| $env:AZURE_TOKEN_CREDENTIALS = "dev" |
| |
| # Bash / Linux / macOS |
| export AZURE_TOKEN_CREDENTIALS=dev |
| ``` |
|
|
| Or add `AZURE_TOKEN_CREDENTIALS=dev` to your `.env` file. |
|
|
| > Requires `azure-identity >= 1.23.0`. See [Exclude a credential type category](https://learn.microsoft.com/azure/developer/python/sdk/authentication/credential-chains?tabs=dac#exclude-a-credential-type-category) for details. |
|
|
| ### Prerequisite: `az login` |
|
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| The pipeline uses Azure AD token-based auth. You must be logged in: |
| ```bash |
| az login |
| az account show # verify |
| ``` |
|
|
