Amazon DynamoDB Backup & Restore

AWS DynamoDB supports On-Demand backups and Point-In-Time-Recovery (PITR) backups.    There is also SYSTEM backups for DynamoDB - for example - these are created when a DynamoDB table is deleted. 

There are two options available for creating and managing DynamoDB on-demand backups:    AWS Backup service & DynamoDB. 

Option 1 : Using the DynamoDB  method for a DynamoDB snapshot backup. Using the dynamoDB api 

--create backup to DynamoDB API

aws dynamodb create-backup --table-name <REPLACE_WITH_DYNAMODB_TBL> --backup-name  <REPLACE_WITH_DYNAMODB_TBL_BACKUP_NAME> 

Option 2 : Using the AWS Backup method for a snapshot , using the the backup api

aws backup start-backup-job --backup-vault-name <REPLACE_BACKUP_VAULT_NAME> --resource-arn <REPLACE_WITH_DYNAMO_TABLE_ARN> --iam-role-arn <REPLACE_WITH_IAM_ROLE_ARN> --region <REPLACE_WITH_REGION_NAME>

Notes on DynamoDB backups

1) When PITR is enabled , DynamoDB maintains continuous backups and can restore to any point in time between the EarliestRestorableDateTime and LatestRestorableDateTime

2) PITR needs to be enabled on a DynamoDB table by table basis 

How to check the PITR status 

Example 1 : PITR status is enabled

aws dynamodb describe-continuous-backups --table-name abc1

{
    "ContinuousBackupsDescription": {
        "ContinuousBackupsStatus": "ENABLED",
        "PointInTimeRecoveryDescription": {
            "PointInTimeRecoveryStatus": "ENABLED",
            "EarliestRestorableDateTime": "2022-11-02T13:36:19.311000+00:00",
            "LatestRestorableDateTime": "2022-12-07T13:31:19.311000+00:00"
        }
    }
}

Example 2: PITR is disabled

aws dynamodb describe-continuous-backups --table-name abc2


{
    "ContinuousBackupsDescription": {
        "ContinuousBackupsStatus": "ENABLED",
        "PointInTimeRecoveryDescription": {
            "PointInTimeRecoveryStatus": "DISABLED"
        }
    }
}

How to enable PITR on a DynamoDB table

aws dynamodb update-continuous-backups --table-name MyDynamoDBtable --point-in-time-recovery-specification PointInTimeRecoveryEnabled=true

How to Restore a DynamoDB to point-in-time  table using AWS CLI

Note: PITR recovery restores to a new table

OPTION 1 : Restore to the latest Restorable times 

aws dynamodb restore-table-to-point-in-time --source-table-name MyDynamoDBtable --target-table-name MyDynamoDBtable-restore  --use-latest-restorable-time

OPTION 2 : Restore to a specific point in time 

Note: To get a specific restore-date-time 

aws dynamodb restore-table-to-point-in-time --source-table-name <replace_with_source_tbl_> --target-table-name <replace_with_target_tbl> --no-use-latest-restorable-time --restore-date-time <replace_with_restore_date_time>

How to Restore a DynamoDB when the backup is generated by the SYSTEM . For example , when the backup is created automatically when a DynamoDB table is deleted.

Step 1 : Check for the existence of a SYSTEM DynamoDB table 

aws dynamodb list-backups --table-name <replace_with_the_DynamoDB table>  --backup-type SYSTEM --output table

Step 2 : Use the BackupARN value to restore the database

aws dynamodb restore-table-from-backup --target-table-name <replace_with_table_name> --backup-arn <replace_with_backup_arn>

Along with data, the following settings are also restored to the new DynamoDB table:

Global secondary indexes (GSIs)
Local secondary indexes (LSIs)
Provisioned read and write capacity
Encryption settings

There are a few settings that will need to be manually set up on the restored table and are not copied over:

Auto scaling policies
AWS Identity and Access Management (IAM) policies
AWS CloudWatch metrics and alarms
Tags
Stream settings
Time-to-Live (TTL) settings
Point-in-time recovery settings

How to Restore A DynamoDB Table - assuming the AWS Backup plan is used

--get the DynamoDB table Resource ARN

aws dynamodb describe-table --table-name <replace_with_DynamoDB_table_name> --query Table.TableArn

--get the backup resource ARN .This query will return  1 or more backup recovery points - with date and Recovery PointARN. Select the RecoveryPointARN as required

aws backup list-backup-jobs --by-state COMPLETED --query "BackupJobs[?ResourceArn == '<replace_with_DynamoDB_Resource_ARN>'].[CompletionDate,RecoveryPointArn]"

-- execute the restore command

aws dynamodb restore-table-from-backup --target-table-name  <REPLACE_WITH_TARGET_TBL> --backup-arn  <REPLACE_WITH_BACKUP_RESOURCE_ARN>