Configuration reference

Backup targets, schedule and retention are configured using environment variables.

You can use any environment variable from below also with a _FILE suffix to be able to load the value from a file. This is typically useful when using Docker Secrets or similar. Note that secrets will not be trimmed of leading or trailing whitespace.

In case you encounter double quoted values in your runtime configuration you might still be using an older version of docker-compose. You can work around this by either updating docker-compose or unquoting your configuration values.

You can populate below template according to your requirements and use it as your env_file:

########### BACKUP SCHEDULE


# A cron expression represents a set of times, using 5 or 6 space-separated fields.
#
# Field name   | Mandatory? | Allowed values  | Allowed special characters
# ----------   | ---------- | --------------  | --------------------------
# Seconds      | No         | 0-59            | * / , -
# Minutes      | Yes        | 0-59            | * / , -
# Hours        | Yes        | 0-23            | * / , -
# Day of month | Yes        | 1-31            | * / , - ?
# Month        | Yes        | 1-12 or JAN-DEC | * / , -
# Day of week  | Yes        | 0-6 or SUN-SAT  | * / , - ?
#
# Month and Day-of-week field values are case insensitive.
# "SUN", "Sun", and "sun" are equally accepted.
# If no value is set, `@daily` will be used.
# If you do not want the cron to ever run, use `0 0 5 31 2 ?`.

# BACKUP_CRON_EXPRESSION="0 2 * * *"

# The compression algorithm used in conjunction with tar.
# Valid options are: "gz" (Gzip) and "zst" (Zstd).
# Note that the selection affects the file extension.

# BACKUP_COMPRESSION="gz"

# Parallelism level for "gz" (Gzip) compression.
# Defines how many blocks of data are concurrently processed.
# Higher values result in faster compression. No effect on decompression
# Default = 1. Setting this to 0 will use all available threads.

# GZIP_PARALLELISM=1

# The name of the backup file including the extension.
# Format verbs will be replaced as in `strftime`. Omitting them
# will result in the same filename for every backup run, which means previous
# versions will be overwritten on subsequent runs.
# Extension can be defined literally or via "{{ .Extension }}" template,
# in which case it will become either "tar.gz" or "tar.zst" (depending
# on your BACKUP_COMPRESSION setting).
# The default results in filenames like: `backup-2021-08-29T04-00-00.tar.gz`.

# BACKUP_FILENAME="backup-%Y-%m-%dT%H-%M-%S.{{ .Extension }}"

# Setting BACKUP_FILENAME_EXPAND to true allows for environment variable
# placeholders in BACKUP_FILENAME, BACKUP_LATEST_SYMLINK and in
# BACKUP_PRUNING_PREFIX that will get expanded at runtime,
# e.g. `backup-$HOSTNAME-%Y-%m-%dT%H-%M-%S.tar.gz`. Expansion happens before
# interpolating strftime tokens. It is disabled by default.
# Please note that you will need to escape the `$` when providing the value
# in a docker-compose.yml file, i.e. using $$VAR instead of $VAR.

# BACKUP_FILENAME_EXPAND="true"

# When storing local backups, a symlink to the latest backup can be created
# in case a value is given for this key. This has no effect on remote backups.

# BACKUP_LATEST_SYMLINK="backup.latest.tar.gz"

# ************************************************************************
# The BACKUP_FROM_SNAPSHOT option has been deprecated and will be removed
# in the next major version. Please use exec-pre and exec-post
# as documented below instead.
# ************************************************************************
# Whether to copy the content of backup folder before creating the tar archive.
# In the rare scenario where the content of the source backup volume is continuously
# updating, but we do not wish to stop the container while performing the backup,
# this setting can be used to ensure the integrity of the tar.gz file.

# BACKUP_FROM_SNAPSHOT="false"

# By default, the `/backup` directory inside the container will be backed up.
# In case you need to use a custom location, set `BACKUP_SOURCES`.

# BACKUP_SOURCES="/other/location"

# When given, all files in BACKUP_SOURCES whose full path matches the given
# regular expression will be excluded from the archive. Regular Expressions
# can be used as from the Go standard library https://pkg.go.dev/regexp

# BACKUP_EXCLUDE_REGEXP="\.log$"

# Exclude one or many storage backends from the pruning process.
# E.g. with one backend excluded: BACKUP_SKIP_BACKENDS_FROM_PRUNE=s3
# E.g. with multiple backends excluded: BACKUP_SKIP_BACKENDS_FROM_PRUNE=s3,webdav
# Available backends are: S3, WebDAV, SSH, Local, Dropbox, Azure
# Note: The name of the backends is case insensitive. 
# Default: All backends get pruned.

# BACKUP_SKIP_BACKENDS_FROM_PRUNE=

########### BACKUP STORAGE

# The name of the remote bucket that should be used for storing backups. If
# this is not set, no remote backups will be stored.

# AWS_S3_BUCKET_NAME="backup-bucket"

# If you want to store the backup in a non-root location on your bucket
# you can provide a path. The path must not contain a leading slash.

# AWS_S3_PATH="my/backup/location"

# Define credentials for authenticating against the backup storage and a bucket
# name. Although all of these keys are `AWS`-prefixed, the setup can be used
# with any S3 compatible storage.

# AWS_ACCESS_KEY_ID="<xxx>"
# AWS_SECRET_ACCESS_KEY="<xxx>"

# Instead of providing static credentials, you can also use IAM instance profiles
# or similar to provide authentication. Some possible configuration options on AWS:
# - EC2: http://169.254.169.254
# - ECS: http://169.254.170.2

# AWS_IAM_ROLE_ENDPOINT="http://169.254.169.254"

# This is the FQDN of your storage server, e.g. `storage.example.com`.
# Do not set this when working against AWS S3 (the default value is
# `s3.amazonaws.com`). If you need to set a specific (non-https) protocol, you
# will need to use the option below.

# AWS_ENDPOINT="storage.example.com"

# The protocol to be used when communicating with your storage server.
# Defaults to "https". You can set this to "http" when communicating with
# a different Docker container on the same host for example.

# AWS_ENDPOINT_PROTO="https"

# Setting this variable to `true` will disable verification of
# SSL certificates for AWS_ENDPOINT. You shouldn't use this unless you use
# self-signed certificates for your remote storage backend. This can only be
# used when AWS_ENDPOINT_PROTO is set to `https`.

# AWS_ENDPOINT_INSECURE="true"

# If you wish to use self signed certificates your S3 server, you can pass
# the location of a PEM encoded CA certificate and it will be used for
# validating your certificates.
# Alternatively, pass a PEM encoded string containing the certificate.

# AWS_ENDPOINT_CA_CERT="/path/to/cert.pem"

# Setting this variable will change the S3 storage class header.
# Defaults to "STANDARD", you can set this value according to your needs.

# AWS_STORAGE_CLASS="GLACIER"

# Setting this variable will change the S3 default part size for the copy step.
# This value is useful when you want to upload large files.
# NB : While using Scaleway as S3 provider, be aware that the parts counter is set to 1.000.
# While Minio uses a hard coded value to 10.000. As a workaround, try to set a higher value.
# Defaults to "16" (MB) if unset (from minio), you can set this value according to your needs.
# The unit is in MB and an integer.

# AWS_PART_SIZE=16

# You can also backup files to any WebDAV server:

# The URL of the remote WebDAV server

# WEBDAV_URL="https://webdav.example.com"

# The Directory to place the backups to on the WebDAV server.
# If the path is not present on the server it will be created.

# WEBDAV_PATH="/my/directory/"

# The username for the WebDAV server

# WEBDAV_USERNAME="user"

# The password for the WebDAV server

# WEBDAV_PASSWORD="password"

# Setting this variable to `true` will disable verification of
# SSL certificates for WEBDAV_URL. You shouldn't use this unless you use
# self-signed certificates for your remote storage backend.

# WEBDAV_URL_INSECURE="true"

# You can also backup files to any SSH server:

# The URL of the remote SSH server

# SSH_HOST_NAME="server.local"

# The port of the remote SSH server
# Optional variable default value is `22`

# SSH_PORT=2222

# The Directory to place the backups to on the SSH server.

# SSH_REMOTE_PATH="/my/directory/"

# The username for the SSH server

# SSH_USER="user"

# The password for the SSH server

# SSH_PASSWORD="password"

# The private key path in container for SSH server
# Default value: /root/.ssh/id_rsa
# If file is mounted to /root/.ssh/id_rsa path it will be used. Non-RSA keys will
# also work.

# SSH_IDENTITY_FILE="/root/.ssh/id_rsa"

# The passphrase for the identity file

# SSH_IDENTITY_PASSPHRASE="pass"

# The credential's account name when using Azure Blob Storage. This has to be
# set when using Azure Blob Storage.

# AZURE_STORAGE_ACCOUNT_NAME="account-name"

# The credential's primary account key when using Azure Blob Storage. If this
# is not given, the command tries to fall back to using a connection string
# (if given) or a managed identity (if nothing is given).

# AZURE_STORAGE_PRIMARY_ACCOUNT_KEY="<xxx>"

# A connection string for accessing Azure Blob Storage. If this
# is not given, the command tries to fall back to using a primary account key
# (if given) or a managed identity (if nothing is given).

# AZURE_STORAGE_CONNECTION_STRING="<xxx>"

# The container name when using Azure Blob Storage.

# AZURE_STORAGE_CONTAINER_NAME="container-name"

# The service endpoint when using Azure Blob Storage. This is a template that
# can be passed the account name as shown in the default value below.

# AZURE_STORAGE_ENDPOINT="https://{{ .AccountName }}.blob.core.windows.net/"

# Absolute remote path in your Dropbox where the backups shall be stored.
# Note: Use your app's subpath in Dropbox, if it doesn't have global access.
# Consulte the README for further information.

# DROPBOX_REMOTE_PATH="/my/directory"

# Number of concurrent chunked uploads for Dropbox.
# Values above 6 usually result in no enhancements.

# DROPBOX_CONCURRENCY_LEVEL="6"

# App key and app secret from your app created at https://www.dropbox.com/developers/apps/info

# DROPBOX_APP_KEY=""
# DROPBOX_APP_SECRET=""

# Refresh token to request new short-lived tokens (OAuth2). Consult README to see how to get one.

# DROPBOX_REFRESH_TOKEN=""

# In addition to storing backups remotely, you can also keep local copies.
# Pass a container-local path to store your backups if needed. You also need to
# mount a local folder or Docker volume into that location (`/archive`
# by default) when running the container. In case the specified directory does
# not exist (nothing is mounted) in the container when the backup is running,
# local backups will be skipped. Local paths are also be subject to pruning of
# old backups as defined below.

# BACKUP_ARCHIVE="/archive"

########### BACKUP PRUNING

# **IMPORTANT, PLEASE READ THIS BEFORE USING THIS FEATURE**:
# The mechanism used for pruning old backups is not very sophisticated
# and applies its rules to **all files in the target directory** by default,
# which means that if you are storing your backups next to other files,
# these might become subject to deletion too. When using this option
# make sure the backup files are stored in a directory used exclusively
# for such files, or to configure BACKUP_PRUNING_PREFIX to limit
# removal to certain files.

# Define this value to enable automatic rotation of old backups. The value
# declares the number of days for which a backup is kept.

# BACKUP_RETENTION_DAYS="7"

# In case the duration a backup takes fluctuates noticeably in your setup
# you can adjust this setting to make sure there are no race conditions
# between the backup finishing and the rotation not deleting backups that
# sit on the edge of the time window. Set this value to a duration
# that is expected to be bigger than the maximum difference of backups.
# Valid values have a suffix of (s)econds, (m)inutes or (h)ours. By default,
# one minute is used.

# BACKUP_PRUNING_LEEWAY="1m"

# In case your target bucket or directory contains other files than the ones
# managed by this container, you can limit the scope of rotation by setting
# a prefix value. This would usually be the non-parametrized part of your
# BACKUP_FILENAME. E.g. if BACKUP_FILENAME is `db-backup-%Y-%m-%dT%H-%M-%S.tar.gz`,
# you can set BACKUP_PRUNING_PREFIX to `db-backup-` and make sure
# unrelated files are not affected by the rotation mechanism.

# BACKUP_PRUNING_PREFIX="backup-"

########### BACKUP ENCRYPTION

# Backups can be encrypted using gpg in case a passphrase is given.

# GPG_PASSPHRASE="<xxx>"

########### STOPPING CONTAINERS AND SERVICES DURING BACKUP

# Containers or services can be stopped by applying a
# `docker-volume-backup.stop-during-backup` label. By default, all containers and
# services that are labeled with `true` will be stopped. If you need more fine
# grained control (e.g. when running multiple containers based on this image),
# you can override this default by specifying a different value here.
# BACKUP_STOP_DURING_BACKUP_LABEL="service1"

# When trying to scale down Docker Swarm services, give up after
# the specified amount of time in case the service has not converged yet.
# In case you need to adjust this timeout, supply a duration
# value as per https://pkg.go.dev/time#ParseDuration to `BACKUP_STOP_SERVICE_TIMEOUT`.
# Defaults to 5 minutes.

# BACKUP_STOP_SERVICE_TIMEOUT="5m"

########### EXECUTING COMMANDS IN CONTAINERS PRE/POST BACKUP

# It is possible to define commands to be run in any container before and after
# a backup is conducted. The commands themselves are defined in labels like
# `docker-volume-backup.archive-pre=/bin/sh -c 'mysqldump [options] > dump.sql'.
# Several options exist for controlling this feature:

# By default, any output of such a command is suppressed. If this value
# is configured to be "true", command execution output will be forwarded to
# the backup container's stdout and stderr.

# EXEC_FORWARD_OUTPUT="true"

# Without any further configuration, all commands defined in labels will be
# run before and after a backup. If you need more fine grained control, you
# can use this option to set a label that will be used for narrowing down
# the set of eligible containers. When set, an eligible container will also need
# to be labeled as `docker-volume-backup.exec-label=database`.

# EXEC_LABEL="database"

########### NOTIFICATIONS

# Notifications (email, Slack, etc.) can be sent out when a backup run finishes.
# Configuration is provided as a comma-separated list of URLs as consumed
# by `shoutrrr`: https://containrrr.dev/shoutrrr/0.7/services/overview/
# The content of such notifications can be customized. Dedicated documentation
# on how to do this can be found in the README. When providing multiple URLs or
# an URL that contains a comma, the values can be URL encoded to avoid ambiguities.

# The below URL demonstrates how to send an email using the provided SMTP
# configuration and credentials.

# NOTIFICATION_URLS=smtp://username:password@host:587/?fromAddress=sender@example.com&toAddresses=recipient@example.com

# By default, notifications would only be sent out when a backup run fails
# To receive notifications for every run, set `NOTIFICATION_LEVEL` to `info`
# instead of the default `error`.

# NOTIFICATION_LEVEL="error"

########### DOCKER HOST

# If you are interfacing with Docker via TCP you can set the Docker host here
# instead of mounting the Docker socket as a volume. This is unset by default.

# DOCKER_HOST="tcp://docker_socket_proxy:2375"

########### LOCK_TIMEOUT

# In the case of overlapping cron schedules run by the same container,
# subsequent invocations will wait for previous runs to finish before starting.
# By default, this will time out and fail in case the lock could not be acquired
# after 60 minutes. In case you need to adjust this timeout, supply a duration
# value as per https://pkg.go.dev/time#ParseDuration to `LOCK_TIMEOUT`

# LOCK_TIMEOUT="60m"

########### EMAIL NOTIFICATIONS

# ************************************************************************
# Providing notification configuration like this has been deprecated
# and will be removed in the next major version. Please use NOTIFICATION_URLS
# as documented above instead.
# ************************************************************************

# In case SMTP credentials are provided, notification emails can be sent out when
# a backup run finished. These emails will contain the start time, the error
# message on failure and all prior log output.

# The recipient(s) of the notification. Supply a comma separated list
# of addresses if you want to notify multiple recipients. If this is
# not set, no emails will be sent.

# EMAIL_NOTIFICATION_RECIPIENT="you@example.com"

# The "From" header of the sent email. Defaults to `noreply@nohost`.

# EMAIL_NOTIFICATION_SENDER="no-reply@example.com"

# Configuration and credentials for the SMTP server to be used.
# EMAIL_SMTP_PORT defaults to 587.

# EMAIL_SMTP_HOST="posteo.de"
# EMAIL_SMTP_PASSWORD="<xxx>"
# EMAIL_SMTP_USERNAME="no-reply@example.com"
# EMAIL_SMTP_PORT="<port>"