What should I use for application files if I can't rely on local VM disks?

If you can’t rely on local VM disks for application files, the usual answer is to put them on shared, durable network storage or to redesign so the app is stateless.

Common options:

1. Object storage

   • Best for: uploads, documents, images, backups, logs, media
   • Examples: Amazon S3, Azure Blob Storage, Google Cloud Storage
   • Good when files don’t need POSIX-style filesystem semantics

2. Network file storage

   • Best for: apps that expect a mounted filesystem
   • Examples: Amazon EFS / FSx, Azure Files, NFS, SMB/CIFS
   • Useful if the application needs read/write file paths and concurrent access

3. Distributed/cluster file systems

   • Best for: high-scale shared storage needs
   • Examples: Ceph, GlusterFS
   • More operationally complex, but can work when you need filesystem behavior across many hosts

4. Database storage

   • Best for: small files, configuration blobs, metadata
   • Less ideal for large binaries, but sometimes appropriate for transactional consistency

5. Externalize files from the app

   • Store only references/metadata in the app
   • Keep actual files in object storage or file storage
   • This is often the most cloud-native and resilient approach

Practical recommendation

• If these are user-uploaded or generated files: use object storage
• If the app requires a shared mounted directory: use network file storage
• If you’re deploying across ephemeral instances/containers: avoid local disk for anything you need to keep

If you want, I can recommend the best option based on your platform (VMs, Kubernetes, AWS/Azure/GCP, etc.) and the type of files you’re storing.