Blob storage is a type of Azure storage service. Blob Storage stores file data. A blob can be any type of text or binary data, such as a document, media file, or application installer. You can use Blob storage to store content such as backups of files, computers, databases, and devices. Blob storage is also referred to as Object storage.
Use the Azure Settings tab of the Configure General Preferences option from the Administration tab to specify the storage settings to be used through the different backups and restores.
In these settings you can specify the following fields:
- Container Name - the name of the Azure container where the new blob will be created and the backup stored. Every Azure blob must reside in a container. The container forms part of the blob name. If no container with the input name exists, a new one will be created. For more information, click here.
- Azure Storage Account Name - the account name of your storage account. Every object that you store in Azure Storage has a unique URL address. The storage account name forms the subdomain of that address. You can find more information in the following link.
- Azure Access Key - you can use any of the access keys provided to your Azure Storage Account. For more information about Azure Keys, click here.
- Sector Type - define the Azure sector type:
- Public - commercial cloud storage solution.
- Government - cloud storage solution offered to US government customers and their partners.
By default, SQL Safe Backup splits the backup into several files, each with size of 70MB.
You can configure the file size by updating the Windows Registry on the machine hosting the SQL Safe Backup Agent using the following steps:
- Add a new registry REG_DWORD key to HKEY_LOCAL_MACHINE\SOFTWARE\Idera\SQLsafe named AzureFileSize.
- Update the AzureFileSize key to a decimal value of your desired file size. For example, if you want the default file size to be 100MB, the key value should be set to 100.
- Restart all SQL Safe services on the machine.
If there are network connection problems, the backup eventually fails, but files remain on Windows Azure. SQL Safe will not delete these partial backup files. If you want to delete those, you need to do it manually on your Azure account.
Failed Backup
If the backup fails before creating all blobs and only a couple of blobs are created, these blobs will remain in the container unless you manually delete them.
Network Resiliency
Take into account that if you do not enable the network resiliency settings for your backup operations and the network goes down, the operation fails and no retry is executed. When enabling the network resiliency settings and using Azure Blob for backup operations, only the following parameters are applicable:
- Retry Interval - the waiting period before retrying the backup operation.
- Total retry interval - the total time for retrying the backup operation before stopping it.
In restore operations, the resiliency settings remain enabled.
Naming conventions for containers
Taken into account the following naming conventions for your container:
- The container name should be a valid DNS name.
- Names have to start with a letter or number and can contain only letters, numbers, and the dash (-) character.
- Every dash (-) character must be immediately preceded and followed by a letter or number. Consecutive dashes are not permitted in container names.
- All letters should be in lowercase.
- Names can be from three to sixty-three characters long.
Naming blobs and blob sizes
The maximum size for a blob is 70MB. If a backup file is, for example, 160 MB, multiple blobs will be created using the following naming format:
- <blobname>.safe_<i> where <i> is the blob counter
If the blob name is testdb for example, the three blobs created in the container will have the following names: testdb.safe_1 (70MB), testdb.safe_2(70MB), testdb.safe_3(20MB).