openshift-docs/microshift_release_notes/microshift-4-18-release-notes.adoc

:_mod-docs-content-type: ASSEMBLY
[id="microshift-4-18-release-notes"]
= {product-title} {product-version} release notes
include::_attributes/attributes-microshift.adoc[]
:context: release-notes

toc::[]

{product-title-first} provides developers and IT organizations with small-form-factor and edge computing delivered as an application that customers can deploy on top of their managed {op-system-base-full} devices at the edge. Built on {OCP} and Kubernetes, {microshift-short} provides an efficient way to operate single-node clusters in low-resource edge environments.

{microshift-short} is designed to make control plane restarts economical and be lifecycle-managed as a single unit by the operating system. Updates, roll-backs, and configuration changes consist of simply staging another version in parallel and then - without relying on a network - flipping to and from that version and restarting.

[id="microshift-4-18-about-this-release_{context}"]
== About this release
Version {product-version} of {microshift-short} includes new features and enhancements. Update to the latest version of {microshift-short} to receive all of the latest features, bug fixes, and security updates. {microshift-short} is derived from {OCP} {ocp-version} and uses the CRI-O container runtime. New features, changes, and known issues that pertain to {microshift-short} are included in this topic.

You can deploy {microshift-short} clusters to on-premise, cloud, disconnected, and offline environments.

{microshift-short} {product-version} is supported on {op-system-base-full} 9.4.

For lifecycle information, see the link:https://access.redhat.com/product-life-cycles?product=Red%20Hat%20build%20of%20Microshift,Red%20Hat%20Device%20Edge[{product-title} Life Cycle Policy].

[id="microshift-4-18-new-features-and-enhancements_{context}"]
== New features and enhancements

This release adds improvements related to the following components and concepts.

//L3 major categories with features in each as L4s
//[id="microshift-4-18-rhel_{context}"]
//=== {op-system-base-full}
//Image mode for RHEL here if GA; otherwise leave in TP

[id="microshift-4-18-updating_{context}"]
=== Updating
Updating two minor EUS versions in a single step is supported in 4.18. Updates for both single-version minor releases and patch releases are also supported. See xref:../microshift_updating/microshift-update-options.adoc#microshift-update-options[Update options with {product-title} and {op-system-bundle}] for details.

//TODO add new features and enhancements as needed, L4 [discrete] headings

//[id="microshift-4-18-installation_{context}"]
//=== Installation

[id="microshift-4-18-configuring_{context}"]
=== Configuring

[id="microshift-4-18-drop-in-config_{context}"]
==== Drop-in configuration snippets now available
With this release, make configuring your {microshift-short} instances easier by using drop-in configuration snippets. See xref:../microshift_configuring/microshift-using-config-yaml.adoc#microshift-config-snippets_microshift-configuring[Using configuration snippets] for details.

[id="microshift-4-18-ingress-controller-config_{context}"]
==== Control ingress for your use case with additional parameters
With this update, you have greater control over ingress to your {microshift-short} cluster by configuring more parameters. You can use these parameters to define secure connections and the number of connections per pod, plus more. See xref:../microshift_configuring/microshift-ingress-controller.adoc#microshift-ingress-controller_microshift-configuring[Using ingress control for a {microshift-short} cluster] for details.

//[id="microshift-4-18-networking_{context}"]
//=== Networking

//[id="microshift-4-18-nw-feature_{context}"]
//==== tbd nw feature here

//[id="microshift-4-18-storage_{context}"]
//=== Storage

//[id="microshift-4-18-storage_{context}"]
//==== tbd storage feature here

[id="microshift-4-18-running-apps_{context}"]
=== Running applications

[id="microshift-4-18-deleting-resource-manifest_{context}"]
==== Deleting or updating Kustomize manifest resources now documented
With this release, you can delete or upgrade the Kustomize manifest resources. For more information, see xref:../microshift_running_apps/microshift-deleting-resource-manifests.adoc#microshift-deleting-resource-manifests[Deleting or updating Kustomize manifest resources].

[id="microshift-4-18-greenboot-workload-scripts-by-os_{context}"]
==== Greenboot example outputs for image mode for RHEL available
With this release, you can see detailed explanations and example outputs to check whether greenboot workload scripts are running properly. For more information, see xref:../microshift_running_apps/microshift-greenboot-workload-scripts.adoc#microshift-greenboot-test-workload-health-check-script_microshift-greenboot-workload-scripts[Testing a workload health check script].

//[id="microshift-4-18-run-apps_{context}"]
//====  tbd run apps feature here

//[id="microshift-4-18-support_{context}"]
//=== Support

[id="microshift-4-18-backup_and_restore_{context}"]
=== Backup and restore

[id="microshift-4-18-autorecovery-from-manual-backup_{context}"]
==== Automated recovery from manual backups
With this release, you can automatically restore data from manual backups when {microshift-short} fails to start by using the `auto-recovery` feature. For more information, see xref:../microshift_backup_and_restore/microshift-auto-recover-manual-backup.adoc#microshift-auto-recover-manual-backup[Automated recovery from manual backups].

[id="microshift-4-18-doc-enhancements_{context}"]
=== Documentation enhancements

[id="microshift-4-18-install-with-rhel-image-mode_{context}"]
==== Updated content in the {op-system-base} image mode section
With this release, the contents of the "Installing with {op-system-base} image mode" section, which were previously developer-focused, are now updated to be {microshift-short} administrator-focused. For more information, see xref:../microshift_install_bootc/microshift-install-rhel-image-mode.adoc#microshift-install-rhel-image-mode[Using image mode for RHEL with {microshift-short}].

[id="microshift-4-18-tech-preview_{context}"]
== Technology Preview features

Some features in this release are currently in Technology Preview. These experimental features are not intended for production use. Note the following scope of support on the Red{nbsp}Hat Customer Portal for these features:

link:https://access.redhat.com/support/offerings/techpreview[Technology Preview Features Support Scope]

[id="microshift-4-18-rhel-image-mode_{context}"]
=== {op-system-base-full} image mode Technology Preview feature
* You can install {microshift-short} using a `bootc` container image. Image mode for {op-system-base} is a Technology Preview deployment method that uses a container-native approach to build, deploy and manage the operating system as a bootc container image.

See xref:../microshift_install_bootc/microshift-install-rhel-image-mode.adoc#microshift-install-rhel-image-mode[Using image mode for RHEL with {microshift-short}] for more information.

[id="microshift-4-18-deprecated-and-removed-features_{context}"]
== Deprecated and removed features
With this release, the CSI snapshot webhook feature available in previous releases is removed. The webhook is replaced by CEL validation rules for snapshot objects.

//NOTE: Do NOT repeat bug fixes already noted in previous version z-streams
[id="microshift-4-18-bug-fixes_{context}"]
== Bug fixes

[discrete]
[id="microshift-4-18-installation-bug-fixes"]
=== Installation
Previously, the greenboot health check marked some healthy Image mode for {op-system-base} systems as unhealthy due to a 300-second timeout, which was insufficient for systems with slow networks. Beginning in {product-title} 4.18, the default greenboot wait timeout has been extended to 600 seconds to provide more time to download images and ensure accurate system checks. (https://issues.redhat.com/browse/OCPBUGS-47463[OCPBUGS-47463])

//[discrete]
//[id="microshift-4-18-networking-bug-fixes"]
//=== Networking

//[discrete]
//[id="microshift-4-18-support-bug-fixes"]
//=== Support

//check status for next release+
//[id="microshift-4-18-known-issues_{context}"]
//== Known issues

//[id="microshift-4-18-pods-writing-files-excess-memory-limits-crash_{context}"]
//=== tbd known issues

[id="microshift-4-18-asynchronous-errata-updates_{context}"]
== Asynchronous errata updates

Security, bug fix, and enhancement updates for {microshift-short} {product-version} are released as asynchronous errata through the Red Hat Network. All {microshift-short} {product-version} errata are https://access.redhat.com/downloads/content/290/[available on the Red Hat Customer Portal]. For more information about asynchronous errata, read the https://access.redhat.com/product-life-cycles?product=Red%20Hat%20build%20of%20Microshift,Red%20Hat%20Device%20Edge[{microshift-short} Life Cycle].

Red Hat Customer Portal users can enable errata notifications in the account settings for Red Hat Subscription Management (RHSM). When errata notifications are enabled, you are notified through email whenever new errata relevant to your registered systems are released.

[NOTE]
====
Red Hat Customer Portal user accounts must have systems registered and consuming {microshift-short} entitlements for {microshift-short} errata notification emails to generate.
====

This section is updated over time to provide notes on enhancements and bug fixes for future asynchronous errata releases of {microshift-short} {product-version}. Versioned asynchronous releases, for example with the form {microshift-short} {product-version}.z, are detailed in the following subsections.

//TODO verify info prior to merge
[id="microshift-4-18-0-dp_{context}"]
=== RHEA-2025:XXXX - {microshift-short} 4.18.0 bug fix and security update advisory

Issued: DD Month 2025

{product-title} release 4.18.0 is now available. Bug fixes and enhancements are listed in the link:https://access.redhat.com/errata/RHEA-2025:XXXX[RHEA-2025:XXXX] advisory. Release notes for bug fixes and enhancements are provided in this documentation. The images that are included in the update are provided by the {OCP} link:https://access.redhat.com/errata/RHEA-2025:XXXX[RHEA-2025:XXXX] advisory.

See the latest images included with {microshift-short} by xref:../microshift_updating/microshift-list-update-contents.adoc#microshift-get-rpm-release-info_microshift-list-update-contents[listing the contents of the {microshift-short} RPM release package].