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frigate_w_audio/README.md
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Claude ecbe1fc03d Initial Authelia + fail2ban stack
Self-hosted SSO portal with file-based users, SQLite storage, filesystem
notifier, and an iptables-banning fail2ban sidecar. Designed to drop into
a DotheEvo-style ~/docker layout next to a dockerized Caddy on the main
server, joining the same external caddy_net so Caddy reaches Authelia by
container name. fail2ban runs in host network mode with NET_ADMIN/NET_RAW
caps so its bans hit DOCKER-USER and actually drop packets at the edge.

Includes a Caddy snippet (caddy/snippet.example.caddyfile) to merge into
the user's real Caddyfile -- this repo doesn't manage Caddy itself.

https://claude.ai/code/session_013XZ1vmgk78k2PEQ5DmJhF3
2026-04-26 00:26:48 +00:00

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13 KiB
Markdown

# Authelia + fail2ban
Self-hosted authentication portal (Authelia) with an IP-banning sidecar
(fail2ban). Designed to sit next to a dockerized Caddy on the main server
and gate every public subdomain (`cam.example.com`, `doorbell.example.com`,
etc.) behind a single sign-on portal at `auth.example.com`.
```
Internet
|
v
+-------+ caddy_net (docker) +--------------------+
| Caddy |--- forward_auth -------------->| Authelia |
+---+---+ | /api/authz/... |
| reverse_proxy +--------+-----------+
| |
v v
Frigate (IoT VLAN), ntfy, etc. ./authelia/db.sqlite3
./authelia/authelia.log
^
| tail
+------+--------+
| fail2ban | host net
| DOCKER-USER | +iptables
+---------------+
```
- One docker-compose file, two services, one external network (`caddy_net`).
- File-backed users database, SQLite storage, in-memory sessions (no Redis).
- Filesystem notifier -- password reset / new-device emails get written to
a file you `tail -f`. Swap to SMTP later by editing one block.
- fail2ban runs in host network mode and bans via the `DOCKER-USER` chain
so drops happen at the host edge, before traffic reaches the Caddy
container's published ports.
- Caddy is *not* in this repo. You merge a snippet into your real Caddyfile
(see `caddy/snippet.example.caddyfile`).
## Repo layout
```
authelia/
|-- docker-compose.yml
|-- .env.example # copy to .env
|-- .gitignore
|-- README.md # this file
|
|-- authelia/
| |-- configuration.yml # main config -- edit your domain in here
| |-- users_database.yml.example # copy to users_database.yml (gitignored)
| |-- secrets/ # gitignored; secret files mounted as /secrets
| `-- notifications/ # filesystem notifier writes here
|
|-- fail2ban/
| `-- data/ # mounted as /data in the container
| |-- jail.d/
| | |-- authelia.local
| | `-- caddy.local
| `-- filter.d/
| |-- authelia.local
| `-- caddy-4xx.local
|
`-- caddy/
`-- snippet.example.caddyfile # merge into YOUR Caddyfile
```
## Prerequisites
- Docker + docker compose v2 on the main server.
- Caddy already running on the main server, in Docker, joined to an
external network named `caddy_net`. If your network is named differently,
change `caddy_net` everywhere in this repo.
- A root domain you control (the examples use `example.com`). DNS records
for `auth.<root>` and every protected subdomain should point at the
Caddy host's public IP.
- Caddy v2.5.1 or newer (for `forward_auth` directive).
## First-run setup
```bash
# 0) From wherever you keep ~/docker stacks
cd ~/docker
git clone <this repo's url> authelia
cd authelia
# 1) External docker network -- Caddy must already be on this. If it isn't,
# create it now and make sure your Caddy compose joins it.
docker network create caddy_net 2>/dev/null || true
# 2) Bootstrap the secrets directory
mkdir -p authelia/secrets
openssl rand -hex 32 > authelia/secrets/JWT_SECRET
openssl rand -hex 32 > authelia/secrets/SESSION_SECRET
openssl rand -hex 32 > authelia/secrets/STORAGE_ENCRYPTION_KEY
chmod 600 authelia/secrets/*
# 3) Copy and edit the .env
cp .env.example .env
$EDITOR .env # set TZ; pin AUTHELIA_VERSION if you want
# 4) Edit configuration.yml -- replace EVERY `example.com` with your real
# root domain (look for the CHANGE comments)
$EDITOR authelia/configuration.yml
# 5) Create your first user
cp authelia/users_database.yml.example authelia/users_database.yml
$EDITOR authelia/users_database.yml # set username, email, displayname
# Generate the password hash:
docker compose run --rm authelia \
authelia crypto hash generate argon2 --password 'your-real-password'
# Paste the resulting `$argon2id$v=19$m=...` into the user's `password:`.
# 6) Validate the config before starting (catches typos / schema issues)
docker compose run --rm authelia \
authelia validate-config --config /config/configuration.yml
# 7) Bring it up
docker compose up -d
docker compose logs -f authelia # expect "Authelia is listening on ..."
```
## Wire Caddy into Authelia
Open `caddy/snippet.example.caddyfile`. It defines:
- `(authelia)` -- a reusable snippet: `import authelia` in any site block to
gate it.
- `(accesslog)` -- writes Caddy's JSON access log to `/var/log/caddy/access.log`
so fail2ban can watch it.
- `auth.example.com` -- the Authelia portal subdomain.
- Example protected blocks for `cam.example.com` and `doorbell.example.com`.
Copy the relevant blocks into your real Caddyfile, replace `example.com`
with your domain and `192.168.x.x` with real upstream IPs, then reload Caddy:
```bash
docker compose -f ~/docker/caddy/docker-compose.yml exec caddy \
caddy reload --config /etc/caddy/Caddyfile
```
For each protected domain, also add a rule under `access_control.rules` in
`authelia/configuration.yml` (Authelia's default policy is `deny` -- a
domain with no rule will not authenticate). Restart Authelia after editing:
```bash
docker compose restart authelia
```
### Caddy access log path
fail2ban mounts `/var/log/caddy` from the host as read-only. Your Caddy
compose needs to mount the same host path read-write so Caddy can write to
it. In your Caddy compose:
```yaml
services:
caddy:
volumes:
- /var/log/caddy:/var/log/caddy
```
Make sure the host directory exists and is writable by Caddy's UID:
```bash
sudo mkdir -p /var/log/caddy
sudo chown -R 1000:1000 /var/log/caddy # adjust UID to match your Caddy
```
## First login + TOTP enrollment
1. Visit any protected subdomain in a private browser window.
2. Caddy bounces you to `https://auth.<your-domain>/` -- log in with the
username and plaintext password you set above.
3. If the access rule is `two_factor`, Authelia asks you to register a
second factor. Pick **TOTP** and scan the QR with Authy / 1Password /
Google Authenticator / Bitwarden / etc.
4. On first registration Authelia tries to email you a confirmation link.
The filesystem notifier writes it to a file -- grab it with:
```bash
docker compose exec authelia cat /config/notifications/notification.txt
```
Click that link to confirm registration.
5. Re-enter the TOTP code -- you're in.
A successful login sets the `authelia_session` cookie scoped to your root
domain, so it covers every subdomain protected by the same Authelia.
## User management
### Add a user
Append to `authelia/users_database.yml`, generate a hash with
`docker compose run --rm authelia authelia crypto hash generate argon2 --password '...'`,
paste it as `password:`, then `docker compose restart authelia` (or wait
five minutes for the file refresh interval).
### Change a password
Same as above -- re-generate the hash and replace the `password:` field.
### Disable a user
Set `disabled: true` on their entry and restart Authelia.
### Reset their TOTP
```bash
docker compose exec authelia \
authelia storage user totp delete --username yourname \
--config /config/configuration.yml
```
They will be prompted to re-enroll on next login.
## fail2ban
### Verify it's running and watching the right files
```bash
docker compose exec fail2ban fail2ban-client status
docker compose exec fail2ban fail2ban-client status authelia
docker compose exec fail2ban fail2ban-client status caddy-4xx
```
Each `status <jail>` shows the active failures, banned IPs, and the log
file it's tailing.
### Test a filter against your real logs
```bash
# Authelia
docker compose exec fail2ban fail2ban-regex \
/var/log/authelia/authelia.log \
/data/filter.d/authelia.local
# Caddy
docker compose exec fail2ban fail2ban-regex \
/var/log/caddy/access.log \
/data/filter.d/caddy-4xx.local
```
If the failregex doesn't match anything, your log format probably differs
from what the filter expects. For Authelia: confirm `log.format: 'text'`
in `configuration.yml`. For Caddy: confirm the `(accesslog)` snippet is
imported into the site you're testing and that `format json` is set.
### Manually unban an IP
```bash
docker compose exec fail2ban fail2ban-client set authelia unbanip 1.2.3.4
docker compose exec fail2ban fail2ban-client set caddy-4xx unbanip 1.2.3.4
```
### Tune
Per-jail `maxretry`, `findtime`, `bantime` live in
`fail2ban/data/jail.d/*.local`. Edit and restart fail2ban:
```bash
docker compose restart fail2ban
```
The `caddy-4xx` jail's defaults (30 fails / 2 minutes -> 30 minute ban) are
intentionally loose -- a single failed request shouldn't ban you, but a
scanner spraying `/wp-admin`, `/.env`, `/admin.php` etc. will hit it fast.
The `authelia` jail is tighter (3 fails / 10 minutes -> 1 hour ban) on top
of Authelia's own in-app `regulation` (3 fails / 2 minutes -> 5 minute
account lockout), giving you defense in depth: Authelia locks the *user*,
fail2ban bans the *IP*.
## Day-to-day operation
```bash
docker compose ps # everything up?
docker compose logs -f authelia # follow Authelia
docker compose logs -f fail2ban # follow fail2ban
docker compose pull && docker compose up -d # upgrade
```
Bump `AUTHELIA_VERSION` in `.env` when you upgrade Authelia. After any
Authelia upgrade, re-run `validate-config` -- the schema does evolve.
## Troubleshooting
### Redirect loop between site and `auth.<domain>`
Cookie domain mismatch. The `domain` under `session.cookies[]` must be the
*root* domain (e.g. `example.com`), and every protected site must be a
subdomain of that root, served over HTTPS. Mixed `http://` and `https://`
won't work; the cookie is `Secure`.
### "Configuration: session: option 'domain' and option 'cookies' can't be specified at the same time"
Old-style `session.domain: ...` left over from pre-4.38 config. Remove it;
this repo's `configuration.yml` already uses the new `session.cookies[]`
form.
### "access denied" with no login prompt
Default policy is `deny`. Add a rule under `access_control.rules` for the
domain you're hitting and restart Authelia.
### Authelia container restarts forever
```bash
docker compose logs authelia | head -50
```
Most often: missing/empty secret files, bad YAML in `configuration.yml`,
or a `users_database.yml` with an invalid hash.
### Caddy can't resolve `authelia`
Caddy isn't on `caddy_net`. Add `networks: [caddy_net]` to your Caddy
service and `caddy_net: external: true` at the bottom of its compose,
then `docker compose up -d caddy`.
### fail2ban bans don't actually block
Almost always: fail2ban isn't writing to the right iptables chain. With
dockerized Caddy, you need `chain = DOCKER-USER` (already set in the
shipped jail files). Verify:
```bash
sudo iptables -L DOCKER-USER -n
```
You should see jump rules pointing at f2b-* chains.
### Authelia logs show nothing
`log.file_path` is `/config/authelia.log` (i.e. `./authelia/authelia.log`
on the host). If the file isn't appearing, Authelia probably isn't
writing logs because it failed to start -- check `docker compose logs
authelia`.
## Switching the notifier to SMTP
When you have a transactional sender (Mailgun, Postmark, Amazon SES, your
own postfix), replace the `notifier:` block in `authelia/configuration.yml`:
```yaml
notifier:
disable_startup_check: false
smtp:
address: 'smtps://smtp.example.com:465'
username: 'authelia@example.com'
sender: 'Authelia <authelia@example.com>'
subject: '[Authelia] {title}'
# Password loaded via AUTHELIA_NOTIFIER_SMTP_PASSWORD_FILE
```
Add the password file:
```bash
echo 'your_smtp_password' > authelia/secrets/SMTP_PASSWORD
chmod 600 authelia/secrets/SMTP_PASSWORD
```
And add to `docker-compose.yml` under the authelia service `environment:`:
```yaml
- AUTHELIA_NOTIFIER_SMTP_PASSWORD_FILE=/secrets/SMTP_PASSWORD
```
Restart and verify with `docker compose logs authelia` -- expect a
"Notifier SMTP startup check successful" line.
## Security notes
- `.env`, `authelia/secrets/*`, `authelia/users_database.yml`,
`authelia/db.sqlite3*`, and the notifications file are all gitignored.
Verify with `git status` before every commit.
- Authelia is *not* port-mapped to the host. Only containers on
`caddy_net` can reach it, and only Caddy is configured to forward
unauthenticated traffic to it via `forward_auth`.
- The TOTP secrets in the SQLite DB are encrypted at rest with
`STORAGE_ENCRYPTION_KEY`. Lose that file and you lose every user's TOTP
-- back it up alongside the DB.
- `regulation` is per-user; fail2ban is per-IP. Both are on by default.
- The shipped `caddy-4xx` filter ignores `favicon.ico`, `robots.txt`, and
Apple touch icons so accidentally-missing static assets don't ban your
own browser. Add to `ignoreregex` if other false-positives show up in
`fail2ban-regex` testing.
## What's next
Once this is steady-state:
- Add OIDC clients in Authelia for apps that speak OIDC natively (Grafana,
Gitea, etc.) -- they'll do real SSO without forward-auth headers.
- Switch the filesystem notifier to SMTP (see above).
- Consider a backup job for `authelia/db.sqlite3` and `authelia/secrets/`
-- losing either is a recovery mess.