Release History

• vv3.2.1
• vv3.2.0
• vv3.1.4
• vv3.1.3
• vv3.1.2
• vv3.1.1
• v3.1.0
• v3.0.12
• v3.0.11
• v3.0.10
• v3.0.9
• v3.0.8
• v3.0.7
• v3.0.6
• v3.0.5
• v3.0.4
• v3.0.3
• v3.0.2
• v3.0.1
• v3.0.0
• v1.5.6
• v1.5.5
• v1.5.4
• v1.5.3
• v1.5.2
• v1.5.1
• v1.5.0
• v1.4.2
• v1.4.1
• v1.4.0
• v1.3.3
• v1.3.2
• v1.3.1
• v1.3.0

Release notes

vv3.2.1(2026-03-25)

Added

• Informational Tags can now be disabled entirely via EnableInformationalTagging parameter on the hub stack

Fixed

• IS_Error tag now records timestamp of first-occurrence rather than being updated every scheduling interval
• IS_ManagedBy tag now records hub stack ARN instead of name

Security

• Updated black to mitigate CVE-2026-32274

vv3.2.0(2026-03-12)

Fixed

• Fixed additional deployment/undeployment race-case scenarios in remote template
• Fixed RDS informational error tags not being correctly applied
• Solution log groups now correctly named {stackName}-{namespace}-{logGroupName} instead of instance-scheduler-on-aws-{namespace}-{logGroupName}
• Fixed TagEvent forwarding EventRules not updating when changing ScheduleTagKey parameter on stacks

Changed

• Re-added support for EC2 Instance resizing using the `periodName@size` pattern in schedule configurations

Security

• Updated minimatch to mitigate CVE-2026-26996, CVE-2026-27903, and CVE-2026-27904
• Updated joserfc to mitigate CVE-2026-27932

vv3.1.4(2026-02-23)

Fixed

• Fixed EC2 registration filters to properly ignore all non-instance resources that get tagged
• Fixed ICE retry lambda missing environment variable error

Security

• Updated fast-xml-parser to mitigate CVE-2026-26278
• Updated Werkzeug to mitigate CVE-2026-27199

vv3.1.3(2026-02-11)

Fixed

• Fixed retain_running flag activating on normal start actions and overriding the scheduled start action.

vv3.1.2(2026-02-06)

Fixed

• Fixed deployment errors in GovCloud
• Namespace now properly applied to EventRules allowing for multiple parallel deployments of Instance Scheduler in the same account
• Fixed CFN Stack Delete race-case that would sometimes cause resource deregistration to fail and hang the stack
• Fixed RDS registration filters to properly handle when cluster-snapshot resources are tagged.

Changed

• Updated registration logs to include `resource` context key containing the registered/deregistered resource's ARN

vv3.1.1(2026-01-13)

Added

• IS-Error tag now includes time of when the error was last updated

Changed

• Short-circuit configuration errors (Unknown Schedule, Unsupported Resource, Incompatible Schedule) no longer reported to event-bus as scheduling errors

Security

• Updated urllib3 to mitigate CVE-2026-21441
• Updated Werkzeug to mitigate CVE-2026-21860

v3.1.0(2025-12-18)

Added

• Added Support for License Manager controlled EC2 instances
• Added `IS-MinDesiredMax` control tag to ASGs to simplify management of ASG resources
• Added support for retrying Insufficient Capacity Errors on EC2 with different instance sizes
• ['Use `IS-PreferredInstanceTypes` control tag to specify acceptable instance types that can be used']
• Added `IS-GlobalEvents` (in hub) and `IS-LocalEvents` (in all targets) event buses that will output the following events:
• ['`Resource Registered` whenever a resource is registered for scheduling', '`Scheduling Action` whenever a resource is started/stopped by the scheduler']

Changed

• Instance Scheduler now listens for tagging events and tracks managed instances in an internal `registry` table
• ['Optimized scheduling orchestration to improve scaling performance for larger deployments.']
• Managed regions is now defined per-account in the remote stack rather than globally on the hub stack
• Instance Scheduler will now apply informational tags to resources during scheduling:
• ['`IS-ManagedBy` -- indicates location of Instance Scheduler Hub Stack', '`IS-LastAction` -- displays the last successful action taken by instance scheduler', '`IS-Error` -- displays error code when errors occur during scheduling', '`IS-ErrorMessage` -- displays additional information about the most recent error code']
• Cleaned up Operational Insights dashboard and added widgets to display ASG scheduling metrics
• Brought ASG scheduling flows inline with other scheduling flows
• Moved logs into dedicated `-scheduling-logs` and `-administrative-logs` log groups
• Restructured logs to use structured-logging optimized for log-insights queries and provided pre-canned queries that can be used in the CloudWatch Log Insights console.

Removed

• Listing member accounts via an SSM parameter (passing `{param: ssm-param-name}` to the accounts parameter on the hub stack) is no longer supported.
• Scheduled instance resizing (defining `period-name@size` in a schedule) is no longer supported.
• Started/Stopped tags configuration parameter on hub stack has been removed (replaced by informational tagging feature)
• Deployments of more than 40 accounts must now use organizations mode
• EnableXXXScheduling properties removed -- Service-specific scheduling is now handled automatically in response to tagging events
• Removed per-schedule metrics from cloudwatch

Security

• Updated Filelock to mitigate CVE-2025-68146
• Updated js-yaml to mitigate CVE-2025-64718

v3.0.12(2025-12-10)

Security

• Updated urllib3 to mitigate CVE-2025-66471

v3.0.11(2025-07-29)

Security

• Updated urllib3 to mitigate CVE-2025-50182
• Updated requests to mitigate CVE-2024-47081
• Updated brace-expansion to mitigate CVE-2025-5889
• Updated OpenSSL to mitigate CVE-2024-12797

Changed

• Minimum supported version of scheduler CLI raised from Python 3.9 to Python 3.11

Removed

• Removed AppRegistry integration

v3.0.10(2025-05-22)

Security

• Upgrade setuptools to mitigate CVE-2025-47273
• Upgrade aws-cdk to mitigate GHSA-5pq3-h73f-66hr and GHSA-qc59-cxj2-c2w4

Changed

• Updated Lambda default memory size to 512MB

v3.0.9(2025-04-10)

Security

• Upgrade Jinja2 to mitigate CVE-2025-27516
• Upgrade aws-cdk to mitigate CVE-2025-2598
• Upgrade esbuild to mitigate GHSA-67mh-4wv8-2f99
• Upgrade OpenSSL to mitigate CVE-2024-12797

Changed

• Reintroduced --use-maintenance-window flag for schedules. The flag will be enabled by default but can be set to false to disable RDS preferred maintenance windows and EC2 maintenance windows

v3.0.8(2025-01-31)

Changed

• Upgrade AWS Powertools from V2 to V3

Security

• Upgrade jinja to mitigate CVE-2024-56201 and CVE-2024-56326

v3.0.7(2024-11-21)

Security

• Upgrade cross-spawn to mitigate CVE-2024-21538

v3.0.6(2024-11-07)

Changed

• RDS instances will now be automatically started 10 minutes prior to their preferred maintenance windows

Fixed

• Clamped role session name to 64 characters to fix scenario where longer namespaces could cause runtime errors during sts assume
• Fixed long-term retry logic for EC2/RDS scheduling. EC2 and RDS will now retry start actions on instances that failed during the previous scheduling cycle
• Fixed AccessDenied error when spoke account self-registration process attempted to create a log group

Security

• Upgrade Werkzeug to mitigate CVE-2024-49766 and CVE-2024-49767

v3.0.5(2024-10-01)

Fixed

• Fixed bug in Nth weekday logic that would sometimes cause Nth weekday to be interpreted as 1 week too early

Changed

• added rds:CreateDBSnapshot and rds:AddTagsToResource snapshot to scheduling roles to support recent changes to RDS IAM requirements.

Security

• Upgrade pyca/cryptography to mitigate GHSA-h4gh-qq45-vh27

v3.0.4(2024-08-30)

Fixed

• Fixed China region compatibility issues by adding new -cn variants of solution stack templates
• Fixed bug in RDS Scheduling Logic that would cause the scheduler to crash when more than 100 tagged RDS instances were present in a single scheduling target

Added

• added SECURITY.md file with instructions on how security issues can be reported to AWS

v3.0.3(2024-07-31)

Security

• Upgrade fast-xml-parser to mitigate CVE-2024-41818

v3.0.2(2024-07-24)

Fixed

• Fixed an error that caused CloudFormation-managed schedules using the (now deprecated) UseMaintenanceWindow flag be an un-updatable

Security

• Upgrade Certifi to mitigate CVE-2024-39689

v3.0.1(2024-06-27)

Changed

• Scheduler CLI installation process now uses a version-agnostic installation process
• Lambda memory size for orchestration and asg scheduling lambdas is now configurable

Fixed

• Fixed an error that would cause maintenance window scheduling to fail when the SSM api returned expired maintenance windows without a `NextExecutionTime` property
• Fixed KMS encryption key being deleted when DynamoDB tables were configured to be retained on stack delete
• Fixed an error that caused ASG schedule updates to fail when more than 5 schedules were updated at once
• Fixed a possible name conflict with Operational Insights Dashboard when deploying multiple copies of Instance Scheduler to the same account

Security

• Upgrade braces to mitigate CVE-2024-4068
• Upgrade urllib3 to mitigate CVE-2024-37891

Removed

• Removed e2e testing pipeline from public assets

v3.0.0(2024-06-05)

Added

• Added support for scheduling of Neptune and DocumentDB clusters
• Added support for scheduling of ASG through the automatic creation of Scheduled Scaling Rules from configured schedules
• Added optional Operational Insights Dashboard to CloudWatch for monitoring and insights into solution performance
• Added support for using multiple EC2 maintenance windows with a single schedule
• Added ability to specify KMS keys that Instance Scheduler should be granted permissions to use when starting EC2 instances with encrypted EBS volumes

Changed

• Separated "Scheduled Services" parameter into individual enabled/disabled parameters for each supported service
• Upgrade Python runtime to 3.11
• Extensive refactoring to internal code to improve code quality and testability
• CloudWatch metrics feature renamed to "Per Schedule Metrics" and integrated with new Operational Insights Dashboard
• DynamoDB Deletion Protection now enabled by default on solution DynamoDB tables.
• Refactored maintenance window dynamodb table to be more cost-efficient at scale
• Updated schedule logs to include SchedulingDecision entries for all decisions made by the EC2/RDS schedulers.
• Scheduler CLI will now error when attempting to overwrite schedules managed by CloudFormation

Removed

• Configuration settings from CloudFormation parameters no longer duplicated in DynamoDB
• Remove deprecated "overwrite" Schedule flag (distinct from still-supported "override" flag)
• Cloudwatch Metrics feature replaced with Operational Monitoring

Fixed

• Fixed deployment error in China partition, introduced in v1.5.0
• Fixed bug where CloudFormation Schedules used UTC timezone if not specified in template (instead of stack default)
• Fixed bug that would cause the scheduling request handler lambda would hang when trying to scheduler more than 50 RDS instances in the same region
• Fixed bug that would sometimes cause the CFN schedule custom resource to error when many schedules were deployed in parallel
• Fixed bug that would cause spoke stacks to not be correctly deregistered from the hub stack when undeployed
• Fixed bug in cli describe_schedule_usage command that would incorrectly estimate the behavior of schedules using nth weekday expressions
• Fixed bug that would cause schedules using monthday ranges of the format "n-31" to fail to load in months with less days then the end of the range (such as February)
• Fixed configured_in_stack property not being correctly applied to periods deployed by CloudFormation custom resource.

Security

• Break monolith Lambda Function and permissions apart based on principle of least privilege
• Spoke stack trust permissions restricted to only specific lambda roles in the Hub account
• Allow KMS keys for scheduling encrypted EBS volumes to be specified directly on hub/spoke stacks in cloudformation rather needing to be added to scheduling roles manually
• Upgrade Requests to mitigate CVE-2024-35195

v1.5.6(2024-05-10)

Security

• Upgrade werkzeug to mitigate CVE-2024-34069
• Upgrade jinja2 to mitigate CVE-2024-34064

v1.5.5(2024-04-12)

Security

• Upgrade Black to mitigate CVE-2024-21503
• Upgrade idna to mitigate CVE-2024-3651

v1.5.4(2024-04-01)

Security

• Upgrade cryptography to mitigate CVE-2024-26130, CVE-2023-50782, CVE-2024-0727, CVE-2023-49083
• Upgrade Jinja to mitigate CVE-2024-22195
• Upgrade Werkzeug to mitigate CVE-2023-46136
• Upgrade IP to mitigate CVE-2023-42282
• Remove ecdsa to mitigate CVE-2024-23342

v1.5.3(2023-10-22)

Security

• Upgrade @babel/traverse to mitigate CVE-2023-45133
• Upgrade urllib3 to mitigate CVE-2023-45803

v1.5.2(2023-10-09)

Security

• Upgrade cryptography to mitigate GHSA-v8gr-m533-ghj9 and GHSA-jm77-qphf-c4w8
• Upgrade urllib3 to mitigate CVE-2023-43804
• Upgrade certifi to mitigate CVE-2023-37920

v1.5.1(2023-07-24)

Changed

• Add a default start and stop tag
• Use EC2 API more efficiently when filtering EC2 instances for scheduling
• Use system tzdata instead of pytz
• Upgrade Python runtime to 3.10
• Package CLI as sdist and wheel
• Refactoring, type hinting, and improved testing
• Add projen for managing project configuration

Fixed

• Restore Python 3.8 support to CLI
• Fix bug starting EC2 instances at least 10 minutes before maintenance windows
• Fix bug targeting RDS instances that are part of an Aurora cluster for scheduling
• Fix bug where EC2 instances failing to start or stop cause an entire batch to fail to start or stop
• Fix bug where the instance type field on a period in a CloudFormation schedule has no effect
• Fix bug creating CloudWatch log streams when hub scheduling is disabled

Security

• Upgrade cryptography to mitigate CVE-2023-38325 and CVE-2023-2650
• Upgrade aws-cdk-lib to mitigate CVE-2023-35165
• Upgrade fast-xml-parser to mitigate CVE-2023-34104
• Upgrade requests to mitigate CVE-2023-32681
• Upgrade word-wrap to mitigate CVE-2023-26115
• Upgrade semver to mitigate CVE-2022-25883

v1.5.0(2023-04-27)

Added

• Enable solution to support deployment using organization id.
• Lambda code is organized with tox.
• Development/e2e testing pipeline included under source/infrastructure/pipeline capable of automatically deploying and testing solution.
• App Registry integration

Fixed

• Boto Retry module could cause unintended high lambda utilization in case of API failures.
• Cross account scheduling no longer requires IAM role name but only account id.

v1.4.2(2023-01-11)

Fixed

• Upgrade certifi to mitigate [CVE-2022-23491](https://nvd.nist.gov/vuln/detail/CVE-2022-23491).
• Updated issues in bandit scan.
• Updated the CDK version 2.x

v1.4.1(2022-05-12)

Fixed

• Replaced the DescribeLogStreams API call used for getting the next sequence token with PutLogEvents API call to reduce the lambda execution time [#307](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/307)

v1.4.0(2021-04-26)

Added

• Enable solution to be deployed as mutliple stacks in the same account/region

Fixed

• Fix the SSM Maintenance window issue where solution was not fetching SSM Maintenance windows from other account/regions
• Updated logging utility to remove incorrect timestamp
• Fixed issue with scheduler stopping instances at UTC time even when configured with other timezones and Period having weekday configured as Wed#4. [Github Issue](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/238)
• Modified Anonymous Data reporting refer implementation guide for details.
• Removed redundant logging of UTC timestamp along with the Account/Region default stamp in logs in AWS CloudWatch.
• Fixed [Github Issue](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/184) for scheduler-cli.

v1.3.3(2020-08-31)

Fixed

• Update the project to utilize aws cdk constructs for cloudformation template creation.
• Fix the issue for ensuring throttling is avoided to cloudwatch API's from github PR [#177](https://github.com/aws-solutions/instance-scheduler-on-aws/pull/177)

v1.3.2(2020-06-22)

Fixed

• Fix the issue to start instances before the SSM maintenance window beings [#101](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/101)
• Updated the SSM feature to reduce lambda cost
• Added HIBERNATE to the list of valid schedule properties

v1.3.1(2020-03-10)

Fixed

• Fix the issue for new instances launched outside of the schedule period [#127](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/127)
• Fix the issue for retries failures to due incompatible code [#133](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/133)
• Fix the issue for instances being stopped after maintenance window begins [#101](https://github.com/aws-solutions/instance-scheduler-on-aws/issues/101)

v1.3.0(2019-08-26)

Added

• Upgraded the Solution to Python 3.7