To take incremental backups for virtual servers that have incremental backups enabled, use Create Incremental Backup API call.

To create a backup of a disk, use the following method:

POST /settings/disks/:disk_id/backups.xml 
POST /settings/disks/:disk_id/backups.json

XML Request example

curl -i -X POST -H 'Accept: application/xml' -H 'Content-type:application/xml' -u user:password --url http://onapp.test/settings/disks/:id/backups.xml -d '<backup><note>manual backup</note><force_windows_backup>0</force_windows_backup></backup>

JSON Request example

curl -i -X POST -H 'Accept: application/json' -H 'Content-type:application/json' -u user:password --url http://onapp.test/settings/disks/:id/backups.json -d '{"backup":{"note":"manual backup", "force_windows_backup":"0"}}'

 note - optional note

force_windows_backup - for Windows virtual servers only; enabling this option will guarantee the disk backup will be taken regardless of any file system problems

This option should be only used as a last resort. If you enable this option there is no guarantee that backup will be consistent.