The backup solution for [`kiwi-scp`](https://github.com/ldericher/kiwi-scp)
## Quick start
Assuming the backups should be kept locally in `/var/kiwi.backup`, just add this to one of your projects' `docker-compose.yml`.
```yaml
backup:
image: ldericher/kiwi-backup
volumes:
- "$TARGETROOT:/backup/source:ro"
- "/var/kiwi.backup:/backup/target"
```
This will use the default configuration.
- backups the entire service data directory
- stores all backup data on the host file system
- daily incremental backups at night (03:36 am UTC; time chosen by fair dice roll)
- a new full backup once every 4 months
- keeps backups for up to 9 months
- keeps incremental backups for the most recent chain (4 months)
## Customization
The kiwi-backup image allows for extensive customization even without creating a local image variant.
Schedules in environment variables are to be provided [in cron notation](https://crontab.guru/).
### Backup Scope
kiwi-backup will backup everything in its `/backup/source` directory, and you should have no incentive to change that.
To change the backup scope, just change what's mounted into that container directory:
```yaml
backup:
# ...
volumes:
- "$TARGETROOT:/backup/source:ro" # change me!
```
You may of course create additional sources below in the `/backup/source` directory to limit the backup to specific projects or services. For added safety, mount your backup sources read-only by appending `:ro`.
### Backup policy
These are the environment variables to change the basic backup policy.
```yaml
backup:
# ...
environment:
# ...
# when to run backups
# default: "36 03 * * *" <=> daily at 03:36 am
SCHEDULE_BACKUP: "36 03 * * *"
# when to remove failed transactions
# default: "36 04 * * *" <=> daily at 04:36 am
SCHEDULE_CLEANUP: "36 04 * * *"
# how often to opt for a full backup
# default: "4M" <=> every 4 months
FULL_BACKUP_FREQUENCY: "4M"
# how long to keep backups at all
# default: "9M" <=> 9 months
BACKUP_RETENTION_TIME: "9M"
# how many full backup chains with incrementals to keep
# default: "1"
KEEP_NUM_FULL_CHAINS: "1"
# where to put backups
# default: "file:///backup/target" <=> likely in a host-mounted volume
BACKUP_TARGET: "file:///backup/target"
```
### Additional options
There's more environment variables for further customization. You'll likely know if you need to change these.
```yaml
backup:
# ...
environment:
# ...
# when to remove old full backup chains
# default: "36 05 * * SAT" <=> every saturday at 05:36 am
SCHEDULE_RMFULL: "36 05 * * SAT"
# when to remove old incremental backups
# default: "36 05 * * SUN" <=> every sunday at 05:36 am
SCHEDULE_RMINCR: "36 05 * * SUN"
# size of individual duplicity data volumes
# default: "1024" <=> 1GiB
BACKUP_VOLSIZE: "1024"
# Additional options for "duplicity --full-if-older-than" command
OPTIONS_BACKUP: ""
# Additional options for "duplicity cleanup" command
OPTIONS_CLEANUP: ""
# Additional options for "duplicity remove-older-than" command
OPTIONS_RMFULL: ""
# Additional options for "duplicity remove-all-inc-of-but-n-full" command
OPTIONS_RMINCR: ""
```
## Encryption
For effective use of GnuPG encryption, you will need a custom `Dockerfile`.
