Cloud Planning
Part of Cloud storage and backups
Object, block and file storage compared
Compare object, block and file storage by access method, sharing needs and application behaviour before choosing a cloud service.
Choose object storage when software works with named objects through an API, block storage when it needs a disk-like volume, and file storage when users or application instances need shared filesystem paths. The deciding question is how the software reads, changes and shares data.
| Question | Object | Block | File |
|---|---|---|---|
| What does the client address? | An object by name or key | Blocks on an attached volume | Files and directories in a filesystem |
| Typical use | Application assets, exports and backup objects | Virtual machine disks and application data | Shared folders and applications built around file paths |
| Main compatibility check | API and update pattern | Attachment and filesystem ownership | Protocol, locking and permissions |
Object, Block and File Storage: Key Differences
- What does the client address?
- An object by name or key
- Typical use
- Application assets, exports and backup objects
- Main compatibility check
- API and update pattern
- What does the client address?
- Blocks on an attached volume
- Typical use
- Virtual machine disks and application data
- Main compatibility check
- Attachment and filesystem ownership
- What does the client address?
- Files and directories in a filesystem
- Typical use
- Shared folders and applications built around file paths
- Main compatibility check
- Protocol, locking and permissions
Object: retrieve a named item
An object store keeps data under an identifier with associated metadata. Applications commonly use an API to store and retrieve objects. Uploaded images, generated reports and backup files can fit when the application treats each item as a unit.
A folder-like name does not establish the behaviour of a mounted filesystem. If software relies on file locking, directory operations or changing part of a file in place, check the exact object service and integration before moving it.
Block: give a server a volume
A block volume appears to an attached machine as a disk-like device. The operator can create a filesystem and mount it for an application. Amazon EBS provides block-level volumes for EC2 instances, including frequently updated data; its volume and instance must be in the same Availability Zone.
EBS Multi-Attach is limited to supported volume and instance configurations. Attaching one volume to several instances does not create a managed shared filesystem. Concurrent writers require an application or clustered filesystem designed to coordinate them. Check capacity, I/O, attachment rules, snapshots and who maintains the filesystem.
File: share paths
A managed file service presents files and directories over supported protocols. Azure Files provides managed file shares for cloud or on-premises deployments. Google Filestore supports multiple application instances accessing the same file system. Those services are candidates for software built around shared paths.
Check the actual product and tier for protocol support, network reachability, permissions, locking and concurrent-write behaviour. A shared path may ease an existing application's move, while a new application able to use object APIs may have a different choice.
Choose using a representative operation
Write down who opens the data, whether several writers act at once, whether part of a file changes, and what happens when a client disconnects. Rule out interfaces that cannot support that operation. Compare the remaining services on access controls, I/O, recovery and total cost in the intended region.
Choose the interface before considering an object-storage access tier. A cheaper archive class cannot provide filesystem behaviour to software that requires it.
When to use each storage type – Pros and Cons
- Object Storage – ProsScalable for unstructured data; ideal for APIs; supports versioning and lifecycle policies.
- Object Storage – ConsNot suitable for file locking or in-place edits; no native filesystem semantics.
- Block Storage – ProsHigh performance for VMs and databases; supports direct disk access and snapshots.
- Block Storage – ConsRequires manual filesystem management; limited to single-instance attachment (unless Multi-Attach used).
- File Storage – ProsSupports shared paths; compatible with legacy apps; enables concurrent access via protocols like SMB/CIFS.
- File Storage – ConsHigher latency than block; requires careful configuration of permissions and locking.
Key Metrics by Storage Type
- Best for high I/O workloads
- Block storage (e.g., Amazon EBS)
- Best for large-scale unstructured data
- Object storage (e.g., Amazon S3)
- Best for shared filesystem access
- File storage (e.g., Azure Files, Google Filestore)
- Region availability note
- EBS volumes must be in same Availability Zone as EC2 instance.
