---
type: reference
title: qBittorrent
description: qBittorrent download client for the *arr stack — pinned 4.6.7 on FrankBook-Pro, shares the Gluetun WireGuard netns, PBKDF2 WebUI credential recipe.
tags: [qbittorrent, arr-stack, frankbook-pro, gluetun]
timestamp: 2026-09-03T00:00:00Z
---

# qBittorrent

qBittorrent is the torrent download client for the *arr stack. The stack runs on
**FrankBook-Pro** (the Mac mini) as quadlet units inside its podman machine —
not on Dankserver. It receives download requests from Sonarr, Radarr, Lidarr,
and Readarr via category tagging.

**Host:** FrankBook-Pro (podman machine) — **Access:** WebUI on port `8080`,
published by the [[Gluetun]] unit because qBittorrent shares that container's
network namespace (a netns-sharer publishes no ports of its own).

## Facts

| Item | Value |
|------|-------|
| Image | `lscr.io/linuxserver/qbittorrent:4.6.7` — **pinned**, see the pin rationale below |
| Network | `Network=gluetun.container` (torrent egress exits via the WireGuard/ProtonVPN tunnel) |
| Ports | 8080 (WebUI) and 6881 TCP+UDP published on the gluetun unit |
| Env | `PUID=0`, `PGID=0`, `TZ=America/Los_Angeles`, `UMASK_SET=022` |
| Volumes | `/Volumes/COMPLETE/qbittorrent-data:/config`, plus `/Volumes/COMPLETE` and `/Volumes/INCOMPLETE` mounted at identical paths |
| Auth | Web UI username/password (`admin` + generated password); LAN bypass not used |

## Why the 4.6.7 pin exists (2026-09-01)

Readarr's abandoned qBittorrent client rejects qB ≥ 5's **204 empty-body login
success** as `Authentication failure` — a runtime break, not just an API-create
issue. The fleet pins `lscr.io/linuxserver/qbittorrent:4.6.7` while Readarr is
in the stack. **Never unpin to `latest` while Readarr is in the fleet.**

Second trap on any version flip: qB 5.x's shutdown conf rewrite leaves a
`WebUI\Password_PBKDF2=@ByteArray(...)` line that 4.6.7 rejects — every login
then returns "invalid credentials" (the arrs included). Fix = rewrite the same
conf line with the same password while qB is stopped.

## Persistent WebUI credentials (verified 2026-08-30)

qBittorrent 5 mints a **new temporary password at every start** unless a
password is stored in `qBittorrent.conf`. That rotation silently breaks every
arr download client after each reboot. The Web-API has no password endpoint
any more (`/api/v2/app/setPassword` was removed), and the linuxserver image
has no `WEBUI_AUTH` handling — so persistence must be written to the conf
directly, in qb's own `salt:hash` format (`src/base/utils/password.cpp`:
PBKDF2-HMAC-SHA512, 100 000 iterations, 16-byte salt = 4×uint32, then
`base64(salt) + ":" + base64(hash)` as the raw value):

```python
import base64, hashlib, os
salt = os.urandom(16)
h = hashlib.pbkdf2_hmac("sha512", password.encode(), salt, 100000, 64)
val = (base64.b64encode(salt) + b":" + base64.b64encode(h)).decode()
# with the container STOPPED, in [Preferences]:
#   WebUI\Username=admin
#   WebUI\Password_PBKDF2=<val>
```

Then `podman start qbittorrent` and confirm login survives a
`podman restart` — the temp-password rotation stops the moment stored
credentials verify. The chosen value lives host-local in `/home/dank/.qbpass`
(mode 600, owner `dank`) — never in git; every arr download client and
[[Prowlarr]] reference it. (The classic `@ByteArray(salt+hash)` form is WRONG
for qb5: login 401s on it; verify() base64-decodes the two halves separately.)

## Deployment (current)

Quadlet unit `qbittorrent.container` from this repo
(`frankbook-pro/qbittorrent/quadlet/`), installed inside the podman machine at
`/home/core/.config/containers/systemd/qbittorrent.service` by the
frankbook-pro handler in `scripts/deploy-remote.sh`:

```ini
[Container]
ContainerName=qbittorrent
Image=lscr.io/linuxserver/qbittorrent:4.6.7
Network=gluetun.container
Environment=PUID=0
Environment=PGID=0
Environment=TZ=America/Los_Angeles
Environment=UMASK_SET=022
Volume=/Volumes/COMPLETE/qbittorrent-data:/config
Volume=/Volumes/COMPLETE:/Volumes/COMPLETE
Volume=/Volumes/INCOMPLETE:/Volumes/INCOMPLETE

[Service]
TimeoutStartSec=900
Restart=always
```

## Gotchas (verified live)

- Temporary-password rotation on every boot is the default state of an
  untouched qb5 — see the persistence recipe above; without it, all arr
  download clients silently fail queue adds ("Couldn't add release … to
  download queue" in the arr logs) after any restart.
- API login from `curl` needs a `Referer: http://<host>:<port>/` header
  (CSRF protection) or POSTs get rejected even with a valid SID.
- Cookie-name quirk by version: qB 5.x names its WebUI session cookie
  `QBT_SID_<port>`; 4.6.7 uses plain `SID`. Any automation must parse the
  cookie generically (e.g. `grep -oE '[A-Za-z_]*SID[A-Za-z0-9_]*=[^;[:space:]]*'`)
  instead of hard-coding a port-suffixed name, or it fails with 403 cascades
  that never reach qB as failed logins.
- Egress verification for this stack must run **inside the gluetun container**
  (`podman exec gluetun wget -qO- https://ipinfo.io/json`); running the same
  probe one ssh-context out returns the residential IP — a false leak alarm.
- Ensure umask is set to `022` so downloaded files are readable by arr apps.

## See Also

- [[ARR-Stack]] — full *arr stack documentation
- [[Gluetun]] — the WireGuard tunnel this container shares