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---
title: 'Security | Fail2Ban'
hide:
- toc # Hide Table of Contents for this page
---
2016-06-01 02:22:15 +00:00
2023-04-11 18:28:43 +00:00
Fail2Ban is installed automatically and bans IP addresses for 1 week after 2 failed attempts in a time frame of 1 week by default.
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## Configuration files
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If you want to change this, you can easily edit our github example file: [`config-examples/fail2ban-jail.cf`][github-file-f2bjail].
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You can do the same with the values from `fail2ban.conf` , e.g `dbpurgeage` . In that case you need to edit: [`config-examples/fail2ban-fail2ban.cf`][github-file-f2bconfig].
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docs(chore): Normalize for consistency (#2206)
"Brief" summary/overview of changes. See the PR discussion or individual commits from the PR for more details.
---
Only applies to the `docs/content/**` content (_and `setup` command_). `target/` and `test/` can be normalized at a later date.
* Normalize to `example.com`
- Domains normalized to `example.com`: `mywebserver.com`, `myserver.tld`, `domain.com`, `domain.tld`, `mydomain.net`, `my-domain.tld`, `my-domain.com`, `example.org`, `whoami.com`.
- Alternative domains normalized to `not-example.com`: `otherdomain.com`, `otherdomain.tld`, `domain2.tld`, `mybackupmx.com`, `whoareyou.org`.
- Email addresses normalized to `admin@example.com` (in `ssl.md`): `foo@bar.com`, `yourcurrentemail@gmail.com`, `email@email.com`, `admin@domain.tld`.
- Email addresses normalized to `external-account@gmail.com`: `bill@gates321boom.com`, `external@gmail.com`, `myemail@gmail.com`, `real-email-address@external-domain.com`.
- **`faq.md`:** A FAQ entry title with `sample.domain.com` changed to `subdomain.example.com`.
- **`mail-fetchmail.md`:** Config examples with FQDNs for `imap`/`pop3` used `example.com` domain for a third-party, changed to `gmail.com` as more familiar third-party/external MTA.
* Normalize config volume path
- Normalizing local config path references to `./docker-data/dms/config/`: `./config/`, `config/`, \``config`\`, `/etc/` (_volume mount src path prefix_).
- Normalize DMS volume paths to `docker-data/dms/mail-{data,state,log}`: `./mail`, `./mail-state` `./data/mail`, `./data/state`, `./data/logs`, `./data/maildata`, `./data/mailstate`, `./data/maillogs`, (_dropped/converted data volumes: `maildata`, `mailstate`_).
- Other docker images also adopt the `docker-data/{service name}/` prefix.
* `ssl.md` - Use `dms/custom-certs` where appropriate.
* Apply normalizations to README and example `docker-compose.yml`
---
Common terms, sometimes interchangeably used or now invalid depending on context: `mail`, `mail container`, `mail server`, `mail-server`, `mailserver`,`docker-mailserver`, `Docker Mailserver`.
Rough transformations applied to most matches (_conditionally, depending on context_):
- 'Docker Mailserver' => '`docker-mailserver`'
- 'mail container' => '`docker-mailserver`' (_optionally retaining ' container'_)
- 'mail server' => 'mail-server' / '`docker-mailserver`'
- 'mail-server' => '`docker-mailserver`'
- 'mailserver' => 'mail-server' / '`docker-mailserver`'
Additionally I checked `docker run` (_plus `exec`, `logs`, etc, sub-commands_) and `docker-compose` commands. Often finding usage of `mail` instead of the expected `mailserver`
Additionally changes `mailserver` hostname in k8s to `mail` to align with other non-k8s examples.
---
* drive-by revisions
Mostly minor revisions or improvements to docs that aren't related to normalization effort.
2021-09-22 23:29:37 +00:00
The configuration files need to be located at the root of the `/tmp/docker-mailserver/` volume bind (usually `./docker-data/dms/config/:/tmp/docker-mailserver/` ).
2021-08-13 08:30:39 +00:00
docs(chore): Normalize for consistency (#2206)
"Brief" summary/overview of changes. See the PR discussion or individual commits from the PR for more details.
---
Only applies to the `docs/content/**` content (_and `setup` command_). `target/` and `test/` can be normalized at a later date.
* Normalize to `example.com`
- Domains normalized to `example.com`: `mywebserver.com`, `myserver.tld`, `domain.com`, `domain.tld`, `mydomain.net`, `my-domain.tld`, `my-domain.com`, `example.org`, `whoami.com`.
- Alternative domains normalized to `not-example.com`: `otherdomain.com`, `otherdomain.tld`, `domain2.tld`, `mybackupmx.com`, `whoareyou.org`.
- Email addresses normalized to `admin@example.com` (in `ssl.md`): `foo@bar.com`, `yourcurrentemail@gmail.com`, `email@email.com`, `admin@domain.tld`.
- Email addresses normalized to `external-account@gmail.com`: `bill@gates321boom.com`, `external@gmail.com`, `myemail@gmail.com`, `real-email-address@external-domain.com`.
- **`faq.md`:** A FAQ entry title with `sample.domain.com` changed to `subdomain.example.com`.
- **`mail-fetchmail.md`:** Config examples with FQDNs for `imap`/`pop3` used `example.com` domain for a third-party, changed to `gmail.com` as more familiar third-party/external MTA.
* Normalize config volume path
- Normalizing local config path references to `./docker-data/dms/config/`: `./config/`, `config/`, \``config`\`, `/etc/` (_volume mount src path prefix_).
- Normalize DMS volume paths to `docker-data/dms/mail-{data,state,log}`: `./mail`, `./mail-state` `./data/mail`, `./data/state`, `./data/logs`, `./data/maildata`, `./data/mailstate`, `./data/maillogs`, (_dropped/converted data volumes: `maildata`, `mailstate`_).
- Other docker images also adopt the `docker-data/{service name}/` prefix.
* `ssl.md` - Use `dms/custom-certs` where appropriate.
* Apply normalizations to README and example `docker-compose.yml`
---
Common terms, sometimes interchangeably used or now invalid depending on context: `mail`, `mail container`, `mail server`, `mail-server`, `mailserver`,`docker-mailserver`, `Docker Mailserver`.
Rough transformations applied to most matches (_conditionally, depending on context_):
- 'Docker Mailserver' => '`docker-mailserver`'
- 'mail container' => '`docker-mailserver`' (_optionally retaining ' container'_)
- 'mail server' => 'mail-server' / '`docker-mailserver`'
- 'mail-server' => '`docker-mailserver`'
- 'mailserver' => 'mail-server' / '`docker-mailserver`'
Additionally I checked `docker run` (_plus `exec`, `logs`, etc, sub-commands_) and `docker-compose` commands. Often finding usage of `mail` instead of the expected `mailserver`
Additionally changes `mailserver` hostname in k8s to `mail` to align with other non-k8s examples.
---
* drive-by revisions
Mostly minor revisions or improvements to docs that aren't related to normalization effort.
2021-09-22 23:29:37 +00:00
This following configuration files from `/tmp/docker-mailserver/` will be copied during container startup.
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- `fail2ban-jail.cf` -> `/etc/fail2ban/jail.d/user-jail.local`
- `fail2ban-fail2ban.cf` -> `/etc/fail2ban/fail2ban.local`
### Docker-compose config
Example configuration volume bind:
```yaml
volumes:
docs(chore): Normalize for consistency (#2206)
"Brief" summary/overview of changes. See the PR discussion or individual commits from the PR for more details.
---
Only applies to the `docs/content/**` content (_and `setup` command_). `target/` and `test/` can be normalized at a later date.
* Normalize to `example.com`
- Domains normalized to `example.com`: `mywebserver.com`, `myserver.tld`, `domain.com`, `domain.tld`, `mydomain.net`, `my-domain.tld`, `my-domain.com`, `example.org`, `whoami.com`.
- Alternative domains normalized to `not-example.com`: `otherdomain.com`, `otherdomain.tld`, `domain2.tld`, `mybackupmx.com`, `whoareyou.org`.
- Email addresses normalized to `admin@example.com` (in `ssl.md`): `foo@bar.com`, `yourcurrentemail@gmail.com`, `email@email.com`, `admin@domain.tld`.
- Email addresses normalized to `external-account@gmail.com`: `bill@gates321boom.com`, `external@gmail.com`, `myemail@gmail.com`, `real-email-address@external-domain.com`.
- **`faq.md`:** A FAQ entry title with `sample.domain.com` changed to `subdomain.example.com`.
- **`mail-fetchmail.md`:** Config examples with FQDNs for `imap`/`pop3` used `example.com` domain for a third-party, changed to `gmail.com` as more familiar third-party/external MTA.
* Normalize config volume path
- Normalizing local config path references to `./docker-data/dms/config/`: `./config/`, `config/`, \``config`\`, `/etc/` (_volume mount src path prefix_).
- Normalize DMS volume paths to `docker-data/dms/mail-{data,state,log}`: `./mail`, `./mail-state` `./data/mail`, `./data/state`, `./data/logs`, `./data/maildata`, `./data/mailstate`, `./data/maillogs`, (_dropped/converted data volumes: `maildata`, `mailstate`_).
- Other docker images also adopt the `docker-data/{service name}/` prefix.
* `ssl.md` - Use `dms/custom-certs` where appropriate.
* Apply normalizations to README and example `docker-compose.yml`
---
Common terms, sometimes interchangeably used or now invalid depending on context: `mail`, `mail container`, `mail server`, `mail-server`, `mailserver`,`docker-mailserver`, `Docker Mailserver`.
Rough transformations applied to most matches (_conditionally, depending on context_):
- 'Docker Mailserver' => '`docker-mailserver`'
- 'mail container' => '`docker-mailserver`' (_optionally retaining ' container'_)
- 'mail server' => 'mail-server' / '`docker-mailserver`'
- 'mail-server' => '`docker-mailserver`'
- 'mailserver' => 'mail-server' / '`docker-mailserver`'
Additionally I checked `docker run` (_plus `exec`, `logs`, etc, sub-commands_) and `docker-compose` commands. Often finding usage of `mail` instead of the expected `mailserver`
Additionally changes `mailserver` hostname in k8s to `mail` to align with other non-k8s examples.
---
* drive-by revisions
Mostly minor revisions or improvements to docs that aren't related to normalization effort.
2021-09-22 23:29:37 +00:00
- ./docker-data/dms/config/:/tmp/docker-mailserver/
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```
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!!! attention
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DMS must be launched with the `NET_ADMIN` capability in order to be able to install the nftables rules that actually ban IP addresses.
2021-03-01 10:41:19 +00:00
docs(chore): Normalize for consistency (#2206)
"Brief" summary/overview of changes. See the PR discussion or individual commits from the PR for more details.
---
Only applies to the `docs/content/**` content (_and `setup` command_). `target/` and `test/` can be normalized at a later date.
* Normalize to `example.com`
- Domains normalized to `example.com`: `mywebserver.com`, `myserver.tld`, `domain.com`, `domain.tld`, `mydomain.net`, `my-domain.tld`, `my-domain.com`, `example.org`, `whoami.com`.
- Alternative domains normalized to `not-example.com`: `otherdomain.com`, `otherdomain.tld`, `domain2.tld`, `mybackupmx.com`, `whoareyou.org`.
- Email addresses normalized to `admin@example.com` (in `ssl.md`): `foo@bar.com`, `yourcurrentemail@gmail.com`, `email@email.com`, `admin@domain.tld`.
- Email addresses normalized to `external-account@gmail.com`: `bill@gates321boom.com`, `external@gmail.com`, `myemail@gmail.com`, `real-email-address@external-domain.com`.
- **`faq.md`:** A FAQ entry title with `sample.domain.com` changed to `subdomain.example.com`.
- **`mail-fetchmail.md`:** Config examples with FQDNs for `imap`/`pop3` used `example.com` domain for a third-party, changed to `gmail.com` as more familiar third-party/external MTA.
* Normalize config volume path
- Normalizing local config path references to `./docker-data/dms/config/`: `./config/`, `config/`, \``config`\`, `/etc/` (_volume mount src path prefix_).
- Normalize DMS volume paths to `docker-data/dms/mail-{data,state,log}`: `./mail`, `./mail-state` `./data/mail`, `./data/state`, `./data/logs`, `./data/maildata`, `./data/mailstate`, `./data/maillogs`, (_dropped/converted data volumes: `maildata`, `mailstate`_).
- Other docker images also adopt the `docker-data/{service name}/` prefix.
* `ssl.md` - Use `dms/custom-certs` where appropriate.
* Apply normalizations to README and example `docker-compose.yml`
---
Common terms, sometimes interchangeably used or now invalid depending on context: `mail`, `mail container`, `mail server`, `mail-server`, `mailserver`,`docker-mailserver`, `Docker Mailserver`.
Rough transformations applied to most matches (_conditionally, depending on context_):
- 'Docker Mailserver' => '`docker-mailserver`'
- 'mail container' => '`docker-mailserver`' (_optionally retaining ' container'_)
- 'mail server' => 'mail-server' / '`docker-mailserver`'
- 'mail-server' => '`docker-mailserver`'
- 'mailserver' => 'mail-server' / '`docker-mailserver`'
Additionally I checked `docker run` (_plus `exec`, `logs`, etc, sub-commands_) and `docker-compose` commands. Often finding usage of `mail` instead of the expected `mailserver`
Additionally changes `mailserver` hostname in k8s to `mail` to align with other non-k8s examples.
---
* drive-by revisions
Mostly minor revisions or improvements to docs that aren't related to normalization effort.
2021-09-22 23:29:37 +00:00
Thus either include `--cap-add=NET_ADMIN` in the `docker run` command, or the equivalent in `docker-compose.yml` :
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```yaml
cap_add:
- NET_ADMIN
```
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## Running fail2ban in a rootless container
[`RootlessKit`][rootless::rootless-kit] is the _fakeroot_ implementation for supporting _rootless mode_ in Docker and Podman. By default RootlessKit uses the [`builtin` port forwarding driver][rootless::port-drivers], which does not propagate source IP addresses.
It is necessary for `fail2ban` to have access to the real source IP addresses in order to correctly identify clients. This is achieved by changing the port forwarding driver to [`slirp4netns`][rootless::slirp4netns], which is slower than `builtin` but does preserve the real source IPs.
### Docker with `slirp4netns` port driver
For [rootless mode][rootless::docker] in Docker, create `~/.config/systemd/user/docker.service.d/override.conf` with the following content:
```
[Service]
Environment="DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER=slirp4netns"
```
And then restart the daemon:
```console
$ systemctl --user daemon-reload
$ systemctl --user restart docker
```
!!! note
This changes the port driver for all rootless containers managed by Docker.
Per container configuration is not supported, if you need that consider Podman instead.
### Podman with `slirp4netns` port driver
[Rootless Podman][rootless::podman] requires adding the value `slirp4netns:port_handler=slirp4netns` to the `--network` CLI option, or `network_mode` setting in your `docker-compose.yml` .
You must also add the ENV `NETWORK_INTERFACE=tap0` , because Podman uses a [hard-coded interface name][rootless::podman::interface] for `slirp4netns` .
!!! example
```yaml
services:
mailserver:
network_mode: "slirp4netns:port_handler=slirp4netns"
environment:
- ENABLE_FAIL2BAN=1
- NETWORK_INTERFACE=tap0
...
```
!!! note
`slirp4netns` is not compatible with user-defined networks.
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## Manage bans
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You can also manage and list the banned IPs with the [`setup.sh`][docs-setupsh] script.
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### List bans
```sh
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./setup.sh fail2ban
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```
### Un-ban
Here `192.168.1.15` is our banned IP.
```sh
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./setup.sh fail2ban unban 192.168.1.15
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```
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[docs-setupsh]: ../setup.sh.md
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[github-file-f2bjail]: https://github.com/docker-mailserver/docker-mailserver/blob/master/config-examples/fail2ban-jail.cf
[github-file-f2bconfig]: https://github.com/docker-mailserver/docker-mailserver/blob/master/config-examples/fail2ban-fail2ban.cf
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[rootless::rootless-kit]: https://github.com/rootless-containers/rootlesskit
[rootless::port-drivers]: https://github.com/rootless-containers/rootlesskit/blob/v0.14.5/docs/port.md#port-drivers
[rootless::slirp4netns]: https://github.com/rootless-containers/slirp4netns
[rootless::docker]: https://docs.docker.com/engine/security/rootless
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[rootless::podman]: https://github.com/containers/podman/blob/v3.4.1/docs/source/markdown/podman-run.1.md#--networkmode---net
[rootless::podman::interface]: https://github.com/containers/podman/blob/v3.4.1/libpod/networking_slirp4netns.go#L264