server-desktop-01/docs/synology.md

# Synology DS218plus

Operational notes for accessing and navigating the Synology NAS without rediscovering paths.

## Connection

- SSH config alias: `synology`
- Hostname/IP: `192.168.86.31`
- SSH user: `jared`
- SSH key from `~/.ssh/config`: `~/.ssh/id_ed25519_git`
- DSM web UI: `https://192.168.86.31:5001` (HTTPS, self-signed cert) or `http://192.168.86.31:5000` (HTTP); Home Assistant's Synology DSM integration connects on port 5001 with SSL verification disabled.
- Verified NAS hostname: `DS218plus`

Quick check:

```bash
ssh synology 'hostname; id'
```

Expected identity:

```text
DS218plus
uid=1026(jared) gid=100(users) groups=100(users),101(administrators),65536(family)
```

## Volume Paths

**SSH and SFTP use completely different namespaces.** Do not mix them up.

**SSH shell** (`ssh synology`): home is `/var/services/homes/jared` (symlink to `/volume1/homes/jared`). Volume-level paths like `/volume1/...` are accessible.

**SFTP / restic**: shared folders appear directly under `/` as a virtual root. `/volume1` does not exist in SFTP space.

```bash
# SFTP root listing
sftp synology <<'EOF'
ls /
EOF
# → archive  backup  home  homes  music  proxmox_backup
```

Active restic repo (SFTP path):

| Purpose | SFTP path |
| --- | --- |
| Fedora restic repo | `/homes/jared/Backups/fedora-workstation` |

Active restic repo (SSH path, for manual inspection):

| Purpose | SSH path |
| --- | --- |
| Fedora restic repo | `~/Backups/fedora-workstation` = `/volume1/homes/jared/Backups/fedora-workstation` |

## Restic Access

Local `restic` is installed at `/usr/bin/restic`. Credentials are sourced from `~/.credentials`; do not print the file or password.

The active backup script uses:

```bash
source ~/.credentials
restic -r "sftp:${SYNOLOGY_HOST}:${SYNOLOGY_PATH}" snapshots --compact
```

As of 2026-06-05, `~/.credentials` has:

```text
SYNOLOGY_HOST=synology
SYNOLOGY_PATH=/homes/jared/Backups/fedora-workstation
```

The leading path segment `homes` is the Synology shared folder name (visible in DSM), not a filesystem path. `/volume1/homes/...` is the SSH/filesystem equivalent but does not exist in SFTP space.

Repository structure:

```text
config
data/
index/
keys/
locks/
snapshots/
```

## Useful Restic Commands

List snapshots:

```bash
source ~/.credentials
restic -r "sftp:${SYNOLOGY_HOST}:${SYNOLOGY_PATH}" snapshots --compact
```

List a path in the latest snapshot:

```bash
source ~/.credentials
restic -r "sftp:${SYNOLOGY_HOST}:${SYNOLOGY_PATH}" ls latest /home/jared/.ssh
```

Search snapshots for specific files:

```bash
source ~/.credentials
restic -r "sftp:${SYNOLOGY_HOST}:${SYNOLOGY_PATH}" find /home/jared/.ssh/id_rsa /home/jared/.ssh/id_rsa.pub
```

Restore a specific file or directory to a temporary location:

```bash
source ~/.credentials
mkdir -p /tmp/restic-restore
restic -r "sftp:${SYNOLOGY_HOST}:${SYNOLOGY_PATH}" restore latest \
  --target /tmp/restic-restore \
  --include /home/jared/path/to/file
```

## Snapshot State on 2026-06-05

The Fedora restic repo was stalled since 2026-05-24 due to wrong SFTP path in `~/.credentials` (`/home/...` instead of `/homes/...`). Fixed 2026-06-05. Manual backup run confirmed new snapshot saved. Two stale locks were also cleared before the run.

Prior to fix, B2 had been running successfully every night; only Synology was affected.

## SSH Key Recovery Findings

Checked while investigating Hyperthrive VPS access on 2026-05-14:

- Latest restic snapshot `.ssh` contains only `config`, `id_ed25519_git`, `id_ed25519_git.pub`, `id_ed25519_ovh_backup`, `id_ed25519_ovh_backup.pub`, `known_hosts`, and `known_hosts.old`.
- `restic find` did not find `/home/jared/.ssh/id_rsa`, `/home/jared/.ssh/id_rsa.pub`, `id_ed25519_forgejo`, or `id_ed25519_forgejo.pub`.
- `/volume1/backup/jared_backup052124/.ssh` exists but is empty.
- `/volume1/backup/fedora_backup052124/jared/.ssh` exists but is empty.
- No `.ssh` files were found under `/volume1/backup/fedora_backup052124` or `/volume1/backup/fedora_recovery_oct2024` in the checked paths.