How to upload a file from azure blob storage to Linux VM created on azure - azure

Question

I have one large file on my azure blob storage container. I want to move my file from blob storage to Linux VM created on azure> How can I do that using data factory? or any Powershell Command?

Answer 1

The easiest and without any tools is to generate SAS token for the blob and run CURL.
Generate SAS
And then CURL
curl <blob_sas_url> -o output.txt
If you need this automated every time you can generate SAS URL from the script or just use AzCopy.

Answer 2

Please reference this blog：How to copy data to VM from blob storage, it gives you a way to solve the problem with Data Factory:
"To anyone who might get into same problem in future, I solved my problem by using 'copy wizard' present in ADF.
We need to install Data Management Gateway on VM and register it before we use 'copy wizard'.
We need to specify blob storage as source and in destination we need to choose 'File Server Share' option. In 'File Server Share' option we need to specify user credentials which I suppose pipeline uses to login to VM, folder on VM where pipeline will copy the data."
From the Azure Blog Storage document, there is another way can help you Mount Blob storage as a file system with blobfuse on Linux.
Blobfuse is a virtual file system driver for Azure Blob storage. Blobfuse allows you to access your existing block blob data in your storage account through the Linux file system. Blobfuse uses the virtual directory scheme with the forward-slash '/' as a delimiter.
This guide shows you how to use blobfuse, and mount a Blob storage container on Linux and access data. To learn more about blobfuse, read the details in the blobfuse repository.
If you want to use AzCopy, you can reference this document Transfer data with AzCopy and Blob storage. You can download the AzCopy for Linux. It provided the command for upload and download files.
For example, upload file:
azcopy copy "<local-file-path>" "https://<storage-account-name>.<blob or dfs>.core.windows.net/<container-name>/<blob-name>"
For PowerShell, you need to use PowerShell Core 6.x and later on all platforms. It works with Windows and Linux virtual machines using Windows PowerShell 5.1 (Windows only) or PowerShell 6 (Windows and Linux).
You can find the PowerShell commands in this document:Quickstart: Upload, download, and list blobs by using Azure PowerShell
Here is another link talked about Copy Files to Azure VM using PowerShell Remoting 6 (Windows and Linux).
Hope this helps.

Answer 3

You have many options to copy content from the blob store to the disk on the VM:
1. Use AzCopy
2. Use Azure Pipelines - File copy task
3. Use Powershell cmdlets
A lot of content is available on these approaches on SO!

Answer 4

It seems this is not properly documented anywhere so I am sharing the most basic approach which is to use the azcopy tool that is available for both windows/linux OS. This approach doens't need the complexity of creating the credentials/tokens.
Download azcopy
Its simple executable which can be run directly after extraction
Create a managed identity(system-assigned identity) for your Virtual machine. Navigate to VM-> Identity -> Turn the Status to 'ON' -> Save
Now the VM can be assigned permission at the following levels:
Storage account
Container (file system)
Resource group
Subscription
For this case, navigate to storage account -> IAM -> Add role assignment -> Select role 'Storage Blob Data Contributor' -> Assign access to 'Virtual machine' -> Select the desired VM -> SAVE
NOTE: If you give access to the VM on IAM properties of a Resource Group, the VM will be able to access all the storage accounts of the RG.
Login to VM and assume the identity (run the command from the same location where the azcopy is located)
For windows : azcopy login --identity
For linux : ./azcopy login --identity
Upload or download the files now:
azcopy cp "source-file" "storageUri/blob-container/" --recursive=true
Example: azcopy cp "C:\test.txt" "https://mystorageaccount.blob.core.windows.net/backup/" --recursive=true
IAM permission can take few minutes to propagate. If you change/add the permissions/access level anywhere, run the azcopy login --identity command again to get the updated identity.
More info on Azcopy is available here