what cloud storage should I use for mixed VM and container file access

For mixed VM and container file access, the best choice is usually shared file storage, not block storage or object storage.

Good options

• NFS / SMB network file share
  • Works well when multiple VMs and containers need the same mounted filesystem
  • Good for shared config, app assets, uploads, logs, and general POSIX-style access
• Managed file services
  • Examples:
    • AWS EFS
    • Azure Files / Azure NetApp Files
    • Google Filestore
  • These are usually the easiest cloud-native answer for mixed compute environments

What to choose by use case

• Need a shared filesystem across many VMs and containers:
  Use managed NFS (common best default)
• Need Windows compatibility:
  Use SMB / Azure Files
• Need very high performance / low latency:
  Use premium managed file storage or NetApp-style storage
• Need simple shared storage for static files, not filesystem semantics:
  Use object storage like S3/GCS/Blob, but only if apps can read/write objects directly

Usually avoid

• Block storage for this use case
  It’s typically attached to one VM only, so it’s not ideal for shared access
• Object storage if your apps expect a normal filesystem
  It’s not a real filesystem and can be awkward for container/VM file sharing

Practical recommendation

If you want one default answer:
Use a managed NFS file share for Linux VM + container mixed access.
If you’re in Azure and Windows is involved, Azure Files is often the better default.

If you want, I can recommend the best option specifically for AWS, Azure, or GCP, or based on whether you need Linux-only, Windows, high performance, or low cost.