file-share/README.md

# file-share

Personal file share server on AWS — Samba for macOS Finder integration and FileBrowser for web-based file management. Accessible exclusively over the site-to-site VPN.

## Architecture

- **EC2** — `t4g.small` (ARM64, Amazon Linux 2023) in the private subnet. The AMI is cached in the committed `cdk.context.json` (`cachedInContext: true`), so deploys never pick up a new AL2023 release implicitly — an AMI change forces instance replacement and must be deliberate (`cdk context --reset <ami key> && cdk synth`).
- **Samba** — SMB file share at `/data/share`, optimized for macOS (`vfs_fruit`)
- **FileBrowser** — Web UI on port 8080, backed by the same `/data/share` directory
- **SFTP** — password auth for user `adam` (`ForceCommand internal-sftp`, same password as SMB); used by Hazel for automated uploads
- **EBS data volume** — `vol-04d951cccacc435b5`, 500 GiB gp3 encrypted, mounted at `/data`. **Unmanaged import**: the stack references it by ID (`Volume.fromVolumeAttributes` + `CfnVolumeAttachment`), so CloudFormation can attach it but can never create, replace, or delete it — the data survives instance replacement and even stack deletion. UserData waits for the attachment, then mounts the existing filesystem; a `blkid` guard ensures a disk that already has a filesystem is never formatted.
- **DLM** — Daily EBS snapshots at 06:00 UTC, 30-day retention (targets the `file-share-backup=true` tag, set directly on the volume)
- **SSM** — Session Manager for instance access (no SSH key)

> **History:** the data volume was originally an inline `blockDevice`, which destroyed data on instance replacement (2026-05-27 incident), then a stack-managed standalone volume, which was orphaned when an uncommitted deploy got reverted by CD (2026-06-05 incident). The unmanaged-import design ends that failure class.

## Access

Requires VPN connection to the office network (10.10.0.0/16).

### Finder (SMB)

1. Finder > Go > Connect to Server
2. Enter `smb://<private-ip>/files`
3. Authenticate with `adam` and the password from `file-share/smb-password` in Secrets Manager

### FileBrowser (Web)

Open `http://<private-ip>:8080` in a browser.

## Secrets

Both stored in AWS Secrets Manager:

| Secret | Purpose |
|---|---|
| `file-share/smb-password` | Samba user password |
| `file-share/filebrowser-password` | FileBrowser admin password |

Create these secrets before deploying the stack:

```bash
aws secretsmanager create-secret --name file-share/smb-password --secret-string '<password>'
aws secretsmanager create-secret --name file-share/filebrowser-password --secret-string '<password>'
```

## Deploy

```bash
npm install
npx cdk deploy
```

The stack outputs the instance's private IP for SMB and FileBrowser access.

## Expanding Storage

The data volume is **not managed by CloudFormation** (imported by ID), so changing a size in `lib/file-share-stack.ts` has no effect. Expand it directly — no downtime:

1. `aws ec2 modify-volume --volume-id vol-04d951cccacc435b5 --size <new-GiB>`
2. Wait for the modification to leave `modifying`: `aws ec2 describe-volumes-modifications --volume-ids vol-04d951cccacc435b5`
3. Resize the filesystem via an SSM session:
   ```bash
   sudo resize2fs /dev/nvme1n1   # xvdf surfaces as nvme1n1 on Nitro instances
   ```