Azure provides us with different access tiers for Azure Blob Storage. Lets try to deep dive into this concepts with an example and implementation.
You can mark this at the Storage Level or at the file level ( blob ).
Hot storage – When we mark the Storage or the blob files as Hot it means we want these files readily accessible. The Data stored in these types of storage are always readily available. In case these files are not being accessed frequently you may end up paying more than expected for the files that are not been accessed as much as it should.
Access Frequency – High
- Storage Cost – Higher
- Access Cost – Lower
Cool Storage – We are talking about those files or storage that are not accessed frequently. Let’s taken an example of a file that summaries your system performance once a month and store it. These types of files you want to access once a while. With this type of storage you pay slightly less for storing but pay more for retrieving the file.
Access Frequency – Low
- Storage Cost – Lower
- Access Cost – Higher
Archive Storage Here we talk about those files which we hardly access much. An example would be Backup files.
Access Frequency – Lowest
- Storage Cost – Lowest
- Access Cost – Highest
Since these files are archived and not readily available it may take hours to retrieve these files.
Also its important to note that if you save files to these storage we should keep it at least for 30 days because Microsoft will charge your for complete 30 days ( irrespective you keep or delete the file ).
You can only set Access tier to Hot / Cool for the below Account kind with Performance set to – Standard.
Note – Premium performance does not support Hot, Cool or Archives access tiers !
- StorageV2 (general purpose v2)
Let me go-ahead and create a Storage account.
- Account kind: StorageV2 (general purpose v2)
- Access tier: Hot
Note – For Blob Storage and General purpose v2 account, Hot and Cool access tiers are set at the Account level. So any blob within this storage will have a default access tier. We can also set the tier at the object level as below. In that case it overrides the default tier. ( Illustration below )
Once my storage is create let me create a container within my Blobs.
Let me upload 3 files to this container with different Blob Type as below. All these uploaded will inferred default account level Tier – Hot (Inferred).
Block Blob (type) – Lets change the access tier of this file so that it overrides the default access tier. You can navigate to the Blob properties – Change the Access tier of this file ( object level access ).
When we try to change the Access Tier for Blob Type – Append Blob and Page Blob. It says as below –
It means – Archive storage and blob-level tiering only supports block blobs. So now my files with Blob Type Block blob has Access Tier – Cool.
You can refer to the following Microsoft link for more insights.