Unable to backup Azure Function App - Invalid Username or Password

Patrik Nordlund 25

I am trying to backup our Function apps to a Storage account using Custom Backups, for most of the apps it works but I have 7 of them that are failing. I start the backup using PowerShell in the same way for all apps and we have a couple of hundred of them.

New-AzWebAppBackup -ResourceGroupName $rgName -Name $appName -StorageAccountUrl $sasUrl -BackupName $backupName

When I check the status with PowerShell

Get-AzWebAppBackupList -ResourceGroupName $rgName -Name $appName

I get Status: Failed and a Log that says the user name or password is incorrect but I do not understand what user name or password is meant since I never enter this.

User's image

Anyone have any ideas or tips?

VenkateshDodda-MSFT 19,621 Reputation points Microsoft Employee

2024-05-23T12:50:22.45+00:00

@Patrik Nordlund Thank for reaching out to Microsoft Q&A, apologize for any inconvenience caused on this.

It look like that your function app is running on dedicated app service plan and you are trying to configure custom backup it is failing with error user name or password is incorrect. Correct me if my understanding is correct?

Can you please check value of the variable $sasUrl whether you are passing storage account url or SAS account of the storage account ?
Patrik Nordlund 25 Reputation points

2024-05-23T13:24:34.99+00:00

Hi @VenkateshDodda-MSFT

Thanks for your reply.

You are correct and I am passing the storage account url + sas token. This works for about 300 of our apps but 7 of them are failing in the same way.
VenkateshDodda-MSFT 19,621 Reputation points Microsoft Employee

2024-05-23T13:33:07.77+00:00

@Patrik Nordlund can you try passing only storage account url and check
Patrik Nordlund 25 Reputation points

2024-05-23T13:54:12.51+00:00

@VenkateshDodda-MSFT but how do I then authenticate towards the storage account?
VenkateshDodda-MSFT 19,621 Reputation points Microsoft Employee

2024-05-24T05:38:35.1+00:00
@Patrik Nordlund Thanks for your response.

Sorry for the confusion. Yes, you need to pass the storage account URL+ SAS token of the blob storage container for the parameter -StorageAccountUrl.

I got confused because of the conflict mentioned in the below cmdlet documetnations.

New-AzWebAppBackup cmdlet documentation says for -StorageAccountUrl parameter you need to pass the storage account url only no need of SAS token.

But this az webapp config backup create cmdlet documentation says for the parameter --container-url storageaccounturl + sas token need to be passed to create a webapp backup.

I have shared the feedback to respective content author to get update the New-AzWebAppBackup cmdlet documentation.

Also, I would suggest you check whether the generated SAS token is valid (not expired) and also, try running the cmdlet New-AzWebAppBackup in debug mode using -debug and review the debugs logs why it is failing.

Hope this helps if you are not fix the issue. I have reached out to privately please do help me with requested details to check further.

Share via

Unable to backup Azure Function App - Invalid Username or Password