Persist files in Azure Cloud Shell

Cloud Shell uses Azure Files to persist files across sessions. On initial start, Cloud Shell prompts you to associate a new or existing fileshare to persist files across sessions.

Note

Bash and PowerShell share the same fileshare. Only one fileshare can be associated with automatic mounting in Cloud Shell.

Azure storage firewall isn't supported for cloud shell storage accounts.

Create new storage

When you use basic settings and select only a subscription, Cloud Shell creates three resources on your behalf in the supported region that's nearest to you:

• Resource group: cloud-shell-storage-<region>
• Storage account: cs<uniqueGuid>
• fileshare: cs-<user>-<domain>-com-<uniqueGuid>

The fileshare mounts as clouddrive in your $HOME directory. This is a one-time action, and the fileshare mounts automatically in subsequent sessions.

The fileshare also contains a 5-GB image that automatically persists data in your $HOME directory. This fileshare is used for both Bash and PowerShell.

Use existing resources

Using the advanced option, you can associate existing resources. When selecting a Cloud Shell region, you must select a backing storage account co-located in the same region. For example, if your assigned region is West US then you must associate a fileshare that resides within West US as well.

When the storage setup prompt appears, select Show advanced settings to view more options. The populated storage options filter for locally redundant storage (LRS), geo-redundant storage (GRS), and zone-redundant storage (ZRS) accounts.

Note

Using GRS or ZRS storage accounts are recommended for additional resiliency for your backing file share. Which type of redundancy depends on your goals and price preference. Learn more about replication options for Azure Storage accounts.

Securing storage access

For security, each user should create their own storage account. For Azure role-based access control (Azure RBAC), users must have contributor access or above at the storage account level.

Cloud Shell uses an Azure fileshare in a storage account, inside a specified subscription. Due to inherited permissions, users with sufficient access rights to the subscription can access all the storage accounts, and file shares contained in the subscription.

Users should lock down access to their files by setting the permissions at the storage account or the subscription level.

The Cloud Shell storage account contains files created by the Cloud Shell user in their home directory, which may include sensitive information including access tokens or credentials.

Supported storage regions

To find your current region you may run env in Bash and locate the variable ACC_LOCATION, or from PowerShell run $env:ACC_LOCATION. File shares receive a 5-GB image created for you to persist your $HOME directory.

Cloud Shell machines exist in the following regions:

Area	Region
Americas	East US, South Central US, West US
Europe	North Europe, West Europe
Asia Pacific	India Central, Southeast Asia

Customers should choose a primary region, unless they have a requirement that their data at rest be stored in a particular region. If they have such a requirement, a secondary storage region should be used.

Secondary storage regions

If a secondary storage region is used, the associated Azure storage account resides in a different region as the Cloud Shell machine that you're mounting them to. For example, you can set your storage account to be located in Canada East, a secondary region, but your Cloud Shell machine is still located in a primary region. Your data at rest is located in Canada, but it's processed in the United States.

Note

If a secondary region is used, file access and startup time for Cloud Shell may be slower.

A user can run (Get-CloudDrive | Get-AzStorageAccount).Location in PowerShell to see the location of their fileshare.

Restrict resource creation with an Azure resource policy

Storage accounts that you create in Cloud Shell are tagged with ms-resource-usage:azure-cloud-shell. If you want to disallow users from creating storage accounts in Cloud Shell, create an Azure resource policy for tags that is triggered by this specific tag.

How Cloud Shell storage works

Cloud Shell persists files through both of the following methods:

• Creating a disk image of your $HOME directory to persist all contents within the directory. The disk image is saved in your specified fileshare as acc_<User>.img at fileshare.storage.windows.net/fileshare/.cloudconsole/acc_<User>.img, and it automatically syncs changes.
• Mounting your specified fileshare as clouddrive in your $HOME directory for direct file-share interaction. /Home/<User>/clouddrive is mapped to fileshare.storage.windows.net/fileshare.

Note

All files in your $HOME directory, such as SSH keys, are persisted in your user disk image, which is stored in your mounted fileshare. Apply best practices when you persist information in your $HOME directory and mounted fileshare.

clouddrive commands

Use the clouddrive command

In Cloud Shell, you can run a command called clouddrive, which enables you to manually update the fileshare that's mounted to Cloud Shell.

List clouddrive

To discover which fileshare is mounted as clouddrive, run the df command.

The file path to clouddrive shows your storage account name and fileshare in the URL. For example, //storageaccountname.file.core.windows.net/filesharename

justin@Azure:~$ df
Filesystem                                          1K-blocks   Used  Available Use% Mounted on
overlay                                             29711408 5577940   24117084  19% /
tmpfs                                                 986716       0     986716   0% /dev
tmpfs                                                 986716       0     986716   0% /sys/fs/cgroup
/dev/sda1                                           29711408 5577940   24117084  19% /etc/hosts
shm                                                    65536       0      65536   0% /dev/shm
//mystoragename.file.core.windows.net/fileshareName 5368709120    64 5368709056   1% /home/justin/clouddrive

Mount a new clouddrive

Prerequisites for manual mounting

You can update the fileshare that's associated with Cloud Shell using the clouddrive mount command.

If you mount an existing fileshare, the storage accounts must be located in your select Cloud Shell region. Retrieve the location by running env and checking the ACC_LOCATION.

The clouddrive mount command

Note

If you're mounting a new fileshare, a new user image is created for your $HOME directory. Your previous $HOME image is kept in your previous fileshare.

Run the clouddrive mount command with the following parameters:

clouddrive mount -s mySubscription -g myRG -n storageAccountName -f fileShareName

To view more details, run clouddrive mount -h, as shown here:

Unmount clouddrive

You can unmount a fileshare that's mounted to Cloud Shell at any time. Since Cloud Shell requires a mounted fileshare to be used, Cloud Shell prompts you to create and mount another fileshare on the next session.

1. Run clouddrive unmount.
2. Acknowledge and confirm prompts.

The unmounted fileshare continues to exist until you manually delete it. After unmounting, Cloud Shell no longer searches for this fileshare in subsequent sessions. To view more details, run clouddrive unmount -h, as shown here:

Warning

Although running this command doesn't delete any resources, manually deleting a resource group, storage account, or fileshare that's mapped to Cloud Shell erases your $HOME directory disk image and any files in your fileshare. This action can't be undone.

PowerShell-specific commands

List clouddrive Azure file shares

The Get-CloudDrive cmdlet retrieves the Azure fileshare information currently mounted by the clouddrive in Cloud Shell.

Unmount clouddrive

You can unmount an Azure fileshare that's mounted to Cloud Shell at any time. The Dismount-CloudDrive cmdlet unmounts an Azure fileshare from the current storage account. Dismounting the clouddrive terminates the current session.

If the Azure fileshare has been removed, you'll be prompted to create and mount a new Azure fileshare in the next session.

Transfer local files to Cloud Shell

The clouddrive directory syncs with the Azure portal storage blade. Use this blade to transfer local files to or from your file share. Updating files from within Cloud Shell is reflected in the file storage GUI when you refresh the blade.

Download files

1. In the Azure portal, go to the mounted file share.
2. Select the target file.
3. Select the Download button.

Upload files

1. Go to your mounted file share.
2. Select the Upload button.
3. Select the file or files that you want to upload.
4. Confirm the upload.

You should now see the files that are accessible in your clouddrive directory in Cloud Shell.

Note

If you need to define a function in a file and call it from the PowerShell cmdlets, then the dot operator must be included. For example: . .\MyFunctions.ps1

Next steps

• Cloud Shell Quickstart
• Learn about Microsoft Azure Files storage
• Learn about storage tags