---
title: "FreeBSD 15.1-RELEASE Release Notes"
sidenav: download
---

:localRel: 15.1
:releaseCurrent: 15.1-RELEASE
:releaseBranch: 15-STABLE
:releasePrev: X.Y-RELEASE
:releaseNext: X.Y-RELEASE
:releaseType: "release"

include::shared/en/urls.adoc[]

= FreeBSD {releaseCurrent} Release Notes
:doctype: article
:toc: macro
:toclevels: 1
:icons: font

== Abstract

[.abstract-title]
The release notes for FreeBSD {releaseCurrent} contain a summary of the changes made to the FreeBSD base system on the {releaseBranch} development line.
This document lists applicable security advisories that were issued since the last release, as well as significant changes to the FreeBSD kernel and userland.
Some brief remarks on upgrading are also presented.

[[intro]]
== Introduction

This document contains the release notes for FreeBSD {releaseCurrent}.
It describes recently added, changed, or deleted features of FreeBSD.
It also provides some notes on upgrading from previous versions of FreeBSD.

The {releaseType} distribution to which these release notes apply represents the latest point along the {releaseBranch} development branch since {releaseBranch} was created.
Information regarding pre-built, binary {releaseType} distributions along this branch can be found at https://www.FreeBSD.org/releases/[].

The {releaseType} distribution to which these release notes apply represents a point along the {releaseBranch} development branch between {releasePrev} and the future {releaseNext}.
Information regarding pre-built, binary {releaseType} distributions along this branch can be found at https://www.FreeBSD.org/releases/[].

This distribution of FreeBSD {releaseCurrent} is a {releaseType} distribution.
It can be found at https://www.FreeBSD.org/releases/[] or any of its mirrors.
More information on obtaining this (or other) {releaseType} distributions of FreeBSD can be found in the link:{handbook}mirrors[Obtaining FreeBSD appendix] to the link:{handbook}[FreeBSD Handbook].

All users are encouraged to consult the release errata before installing FreeBSD.
The errata document is updated with "late-breaking" information discovered late in the release cycle or after the release.
Typically, it contains information on known bugs, security advisories, and corrections to documentation.
An up-to-date copy of the errata for FreeBSD {releaseCurrent} can be found on the FreeBSD Web site.

This document describes the most user-visible new or changed features in FreeBSD since {releasePrev}.
In general, changes described here are unique to the {releaseBranch} branch unless specifically marked as MERGED features.

Typical release note items document recent security advisories issued after {releasePrev}, new drivers or hardware support, new commands or options, major bug fixes, or contributed software upgrades.
They may also list changes to major ports/packages or release engineering practices.
Clearly the release notes cannot list every single change made to FreeBSD between releases; this document focuses primarily on security advisories, user-visible changes, and major architectural improvements.

[[upgrade]]
== Upgrading from Previous Releases of FreeBSD

Binary upgrades between RELEASE versions (and snapshots of the various security branches) are supported using the man:freebsd-update[8] utility.
See the release-specific upgrade procedure, link:../installation/#upgrade-binary[FreeBSD {releaseCurrent} upgrade information], with more details in the FreeBSD handbook link:{handbook}cutting-edge/#freebsdupdate-upgrade[binary upgrade procedure].
This will update unmodified userland utilities, as well as unmodified GENERIC kernels distributed as a part of an official FreeBSD release.
The man:freebsd-update[8] utility requires that the host being upgraded have Internet connectivity.

Source-based upgrades (those based on recompiling the FreeBSD base system from source code) from previous versions are supported, according to the instructions in [.filename]#/usr/src/UPDATING#.

[IMPORTANT]
====
Upgrading FreeBSD should only be attempted after backing up _all_ data and configuration files.
====

[[security-errata]]
== Security and Errata

This section lists the various Security Advisories and Errata Notices since {releasePrev}.

[[security]]
=== Security Advisories

[.informaltable]
[cols="1,1,1", frame="none", options="header"]
|===
| Advisory
| Date
| Topic

|No advisories.
|
|

|===

[[errata]]
=== Errata Notices

[.informaltable]
[cols="1,1,1", frame="none", options="header"]
|===
| Errata
| Date
| Topic

|No notices.
|
|


|===

[[userland]]
== Userland

This section covers changes and additions to userland applications, contributed software, and system utilities.

[[userland-config]]
=== Userland Configuration Changes

[[userland-programs]]
=== Userland Application Changes

[[userland-contrib]]
=== Contributed Software

[[userland-deprecated-programs]]
=== Deprecated Applications

[[userland-libraries]]
=== Runtime Libraries and API

[[kernel]]
== Kernel

This section covers changes to kernel configurations, system tuning, and system control parameters that are not otherwise categorized.

[[kernel-general]]
=== General Kernel Changes

[[drivers]]
== Devices and Drivers

This section covers changes and additions to devices and device drivers since {releasePrev}.

[[drivers-device]]
=== Device Drivers

[[drivers-removals]]
=== Deprecated and Removed Drivers

[[storage]]
== Storage

This section covers changes and additions to file systems and other storage subsystems, both local and networked.

[[storage-general]]
=== General Storage

[[boot]]
== Boot Loader Changes

This section covers the boot loader, boot menu, and other boot-related changes.

[[boot-loader]]
=== Boot Loader Changes

[[network]]
== Networking

This section describes changes that affect networking in FreeBSD.

[[network-general]]
=== General Network

[[hardware]]
== Hardware Support

This section covers general hardware support for physical machines, hypervisors, and virtualization environments, as well as hardware changes and updates that do not otherwise fit in other sections of this document.

Please see link:https://www.freebsd.org/releases/{localRel}R/hardware[the list of hardware] supported by {releaseCurrent}, as well as link:https://www.freebsd.org/platforms/[the platforms page] for the complete list of supported CPU architectures.

[[hardware-virtualization]]
=== Virtualization Support

[[documentation]]
== Documentation

This section covers changes to manual (man:man[1]) pages and other documentation shipped with the base system.

[[man-pages]]
=== Man Pages

[[ports]]
== Ports Collection and Package Infrastructure

This section covers changes to the FreeBSD Ports Collection, package infrastructure, and package maintenance and installation tools.

[[ports-packages]]
=== Packaging Changes

[[future-releases]]
== General Notes Regarding Future FreeBSD Releases
