Google Cloud offers multiple storage services for different use cases. Cloud Storage is the primary object storage service — scalable, durable, and globally accessible.
Cloud Storage
Cloud Storage stores objects (files of any type or size) in containers called buckets. Every object is immutable — you replace rather than modify it. Objects are stored with strong global consistency, meaning reads always reflect the latest write.
Key properties:
- Unlimited capacity — store any number of objects up to 5 TB each
- 11 nines (99.999999999%) durability
- HTTP/HTTPS access via REST APIs or client libraries
- Globally unique bucket names
Storage Classes
Storage classes let you trade retrieval cost for storage cost based on access frequency:
| Class | Min Storage Duration | Retrieval Cost | Best For |
|---|---|---|---|
| Standard | None | None | Frequently accessed data, serving content |
| Nearline | 30 days | Low | Once a month access (backups, data lakes) |
| Coldline | 90 days | Medium | Once a quarter access (disaster recovery) |
| Archive | 365 days | High | Rarely accessed (long-term compliance archives) |
Object Lifecycle Management
Lifecycle rules automatically act on objects when conditions are met. Common examples:
- Move objects to Nearline after 30 days of no access
- Move to Coldline after 90 days, Archive after 365 days
- Delete objects older than 7 years
- Delete non-current versions after 30 days (for versioned buckets)
Lifecycle rules are defined as JSON conditions — the Cloud Console provides a GUI to create them.
Bucket Locations
- Regional: Data stored in a single region. Lowest latency for region-specific apps.
- Dual-region: Data redundantly stored across two specific regions.
- Multi-region: Data stored across a large geographic area (e.g.,
us,eu,asia). Highest availability and geo-redundancy.
Access Control
Cloud Storage supports two access control models:
- Uniform bucket-level access (recommended): All permissions managed via Cloud IAM. Consistent, auditable, simpler.
- Fine-grained access: Combination of IAM and per-object ACLs. Needed for legacy use cases.
For public websites or CDN content, you can make buckets publicly readable. For sensitive data, use private access with signed URLs for temporary, time-limited access.
Other GCP Storage Services
| Service | Type | Best For |
|---|---|---|
| Cloud Storage | Object / Blob | Images, backups, large files, static sites |
| Persistent Disk | Block (attached to VM) | VM OS disks, databases running on VMs |
| Local SSD | Block (ephemeral) | Temp data, high IOPS scratch space |
| Filestore | Managed NFS file | Shared file system for multiple VMs or GKE pods |
| Cloud Storage FUSE | Bucket mounted as filesystem | ML training data, shared read-heavy files |