borgmatic/docs/how-to/provide-your-passwords.md

93 lines
3.2 KiB
Markdown
Raw Normal View History

---
title: How to provide your passwords
eleventyNavigation:
key: 🔒 Provide your passwords
parent: How-to guides
order: 2
---
## Environment variable interpolation
If you want to use a Borg repository passphrase or database passwords with
borgmatic, you can set them directly in your borgmatic configuration file,
treating those secrets like any other option value. But if you'd rather store
them outside of borgmatic, whether for convenience or security reasons, read
on.
<span class="minilink minilink-addedin">New in version 1.6.4</span> borgmatic
supports interpolating arbitrary environment variables directly into option
values in your configuration file. That means you can instruct borgmatic to
pull your repository passphrase, your database passwords, or any other option
values from environment variables. For instance:
```yaml
encryption_passphrase: ${MY_PASSPHRASE}
```
<span class="minilink minilink-addedin">Prior to version 1.8.0</span> Put
this option in the `storage:` section of your configuration.
This uses the `MY_PASSPHRASE` environment variable as your encryption
passphrase. Note that the `{` `}` brackets are required. `$MY_PASSPHRASE` by
itself will not work.
In the case of `encryption_passphrase` in particular, an alternate approach
is to use Borg's `BORG_PASSPHRASE` environment variable, which doesn't even
require setting an explicit `encryption_passphrase` value in borgmatic's
configuration file.
For [database
configuration](https://torsion.org/borgmatic/docs/how-to/backup-your-databases/),
the same approach applies. For example:
```yaml
postgresql_databases:
- name: users
password: ${MY_DATABASE_PASSWORD}
```
<span class="minilink minilink-addedin">Prior to version 1.8.0</span> Put
this option in the `hooks:` section of your configuration.
This uses the `MY_DATABASE_PASSWORD` environment variable as your database
password.
### Interpolation defaults
If you'd like to set a default for your environment variables, you can do so with the following syntax:
```yaml
encryption_passphrase: ${MY_PASSPHRASE:-defaultpass}
```
Here, "`defaultpass`" is the default passphrase if the `MY_PASSPHRASE`
environment variable is not set. Without a default, if the environment
variable doesn't exist, borgmatic will error.
### Disabling interpolation
To disable this environment variable interpolation feature entirely, you can
pass the `--no-environment-interpolation` flag on the command-line.
Or if you'd like to disable interpolation within a single option value, you
can escape it with a backslash. For instance, if your password is literally
`${A}@!`:
```yaml
encryption_passphrase: \${A}@!
```
### Related features
Another way to override particular options within a borgmatic configuration
file is to use a [configuration
override](https://torsion.org/borgmatic/docs/how-to/make-per-application-backups/#configuration-overrides)
on the command-line. But please be aware of the security implications of
specifying secrets on the command-line.
Additionally, borgmatic action hooks support their own [variable
interpolation](https://torsion.org/borgmatic/docs/how-to/add-preparation-and-cleanup-steps-to-backups/#variable-interpolation),
although in that case it's for particular borgmatic runtime values rather than
(only) environment variables.