What is new in Ubuntu 26

Ubuntu 26.04 LTS (Resolute Raccoon), released April 23, 2026, introduces Linux kernel 7.0, updated system and container infrastructure, stronger security defaults, and improvements for cloud environments.

For Linux and network administrators, the biggest areas to understand are kernel changes, networking, container management, security, automation, and Google Cloud Platform (GCP) compatibility.

1. Linux Kernel 7.0

Ubuntu 26.04 LTS ships with Linux kernel 7.0.

Key improvements include:

• Updated hardware and driver support.
• Improved scheduling with sched_ext.
• Real-time kernel availability.
• Improved ARM64 support.
• EtherCAT kernel modules.
• ARM64 Kernel Livepatch support.

Check your kernel:

bash

uname -r

Example output:

text

7.0.0-generic

Check system information:

bash

hostnamectl

Check kernel modules:

bash

lsmod | head

Check kernel messages:

bash

sudo dmesg -T | tail -20

2. Networking Improvements

Ubuntu 26.04 continues to modernize its networking and security stack.

Administrators should pay attention to:

• Updated network drivers.
• Cloud-init networking improvements.
• VLAN, bridge, and bond configuration support.
• Modern TLS defaults.
• Docker nftables firewall backend support.

Check network interfaces

bash

ip -br addr

Example:

text

lo               UNKNOWN  127.0.0.1/8
ens4             UP       10.128.0.10/32

Check routing

bash

ip route

Example:

text

default via 10.128.0.1 dev ens4
10.128.0.0/20 dev ens4 proto kernel scope link

Check DNS configuration

bash

resolvectl status

Test DNS resolution

bash

dig google.com

Test connectivity

bash

ping -c 4 8.8.8.8

Check listening ports

bash

sudo ss -tulpn

Check firewall rules

bash

sudo nft list ruleset

These commands are useful when troubleshooting connectivity, DNS, routing, firewall policies, and application access.

3. TLS and Web Server Security

Ubuntu 26.04 improves default web security.

Updated components include:

• Apache 2.4.66
• Nginx 1.28.2
• TLS 1.2 and TLS 1.3 defaults.
• TLS 1.0 and TLS 1.1 disabled by default in Apache.

Check Apache:

bash

apache2 -v

Check Nginx:

bash

nginx -v

Check supported TLS versions:

bash

openssl version

Test HTTPS connectivity:

bash

openssl s_client -connect google.com:443 -tls1_3

Example:

text

Protocol  : TLSv1.3
Cipher    : TLS_AES_256_GCM_SHA384
Verify return code: 0 (ok)

Check an HTTPS endpoint:

bash

curl -I https://google.com

Example:

text

HTTP/2 301
location: https://www.google.com/

Note: Actual TLS support depends on the remote endpoint and local cryptographic configuration.

4. systemd and Container Changes

Ubuntu 26.04 includes systemd 259.

An important breaking change is the removal of cgroup v1 support.

This matters for:

• Docker workloads.
• Kubernetes nodes.
• Container runtimes.
• Legacy monitoring agents.
• Older container orchestration platforms.

Check systemd:

bash

systemctl --version

Check cgroup version:

bash

stat -fc %T /sys/fs/cgroup

Expected output:

text

cgroup2fs

Check mounted cgroups:

bash

mount | grep cgroup

Check running services:

bash

systemctl --failed

Check container runtime:

bash

docker version

Ubuntu 26.04 also includes Docker 29 and containerd 2.2.

Check Docker containers:

bash

docker ps -a

Check Docker networks:

bash

docker network ls

Inspect a Docker network:

bash

docker network inspect bridge

Important: Test legacy containers before upgrading. Workloads that require cgroup v1 may stop working.

5. Google Cloud Platform (GCP) Improvements

Ubuntu 26.04 is particularly relevant to GCP administrators running Compute Engine workloads.

One major change is that AMD64 cloud images now use the AMD64v3 instruction-set baseline.

This improves compatibility with modern processors but introduces a hardware compatibility consideration.

Important GCP change:

The following older CPU platforms on N1 machine types are no longer supported:

• Intel Sandy Bridge.
• Intel Ivy Bridge.

Review older N1 workloads before migrating.

Check the GCP VM environment

bash

hostnamectl

Check CPU information:

bash

lscpu

Example:

text

Architecture:        x86_64
CPU op-mode(s):      32-bit, 64-bit
CPU(s):              4
Vendor ID:           GenuineIntel

Check the machine metadata:

bash

curl -H "Metadata-Flavor: Google" \
http://metadata.google.internal/computeMetadata/v1/instance/machine-type

Example:

text

projects/123456789/machineTypes/e2-standard-4

Check the GCP project:

bash

gcloud config get-value project

List Compute Engine instances:

bash

gcloud compute instances list

Check instance details:

bash

gcloud compute instances describe INSTANCE_NAME \
--zone=us-central1-a

Check Google Cloud networking

List VPC networks:

bash

gcloud compute networks list

List subnetworks:

bash

gcloud compute networks subnets list

List firewall rules:

bash

gcloud compute firewall-rules list

Check routes:

bash

gcloud compute routes list

These commands help validate GCP connectivity, firewall policies, routing, and infrastructure configuration.

6. GCP Network Performance

When deploying Ubuntu 26.04 on Compute Engine, administrators should review:

• gVNIC support.
• Machine family network bandwidth.
• Tier_1 networking eligibility.
• MTU configuration.
• VPC firewall policies.
• Network interface driver compatibility.

Check network interface drivers:

bash

sudo ethtool -i ens4

Check interface MTU:

bash

ip link show ens4

Change MTU temporarily for testing:

bash

sudo ip link set dev ens4 mtu 1460

Test path MTU:

bash

ping -M do -s 1432 -c 4 8.8.8.8

Note: Use the MTU configured for your actual GCP network path. Do not assume every interface should use 1460.

7. Security Improvements

Ubuntu 26.04 introduces additional security improvements:

• TPM-backed full-disk encryption.
• Improved application permission controls.
• Rust-based system utilities.
• Updated cryptographic defaults.
• ARM64 Livepatch support.

Useful security administration commands:

Check AppArmor:

bash

sudo aa-status

Check SSH configuration:

bash

sudo sshd -T | head -20

Check failed login attempts:

bash

sudo journalctl -u ssh --since today

Check listening services:

bash

sudo ss -tulpn

Check installed security updates:

bash

apt list --upgradable

Update package indexes:

bash

sudo apt update

Upgrade installed packages:

bash

sudo apt upgrade

8. Cloud-init and Infrastructure Automation

Ubuntu 26.04 includes cloud-init 26.1.

This is important for administrators deploying virtual machines through GCP, Terraform, and automated infrastructure pipelines.

Cloud-init improvements include:

• Better network configuration.
• VLAN support.
• Bond configuration.
• Bridge configuration.
• Additional cloud platform detection.

Check cloud-init:

bash

cloud-init --version

Review cloud-init status:

bash

cloud-init status --long

Review cloud-init logs:

bash

sudo tail -50 /var/log/cloud-init.log

Review cloud-init output:

bash

sudo tail -50 /var/log/cloud-init-output.log

Check network configuration:

bash

ls -l /etc/netplan/

Example Netplan configuration:

yaml

network:
  version: 2
  ethernets:
    ens4:
      dhcp4: true

Validate configuration:

bash

sudo netplan generate

Apply configuration:

bash

sudo netplan apply

Always test network changes through a console or another recovery path when managing remote servers.

9. Important Upgrade Considerations

Before migrating Ubuntu 22.04 or 24.04 workloads to Ubuntu 26.04, review the following:

Area	What to check
Kernel	Third-party drivers and modules
systemd	cgroup v1 dependencies
Docker	Docker 29 compatibility
Kubernetes	Runtime and cgroup compatibility
Networking	Netplan, VLANs, bridges and bonds
GCP	N1 CPU platform compatibility
Security	SSH, TLS and AppArmor policies
Automation	cloud-init and Terraform scripts
Monitoring	Logging and monitoring agents

Check the current Ubuntu version:

bash

cat /etc/os-release

Check available disk space:

bash

df -h

Check memory:

bash

free -h

Check installed packages:

bash

apt list --installed

Important: For upgrades from Ubuntu 22.04 LTS, upgrade through Ubuntu 24.04 LTS first. Test workloads and applications in a non-production environment before migration.

10. Commands Every Linux and GCP Administrator Should Know

A quick operational reference:

Task	Command
Kernel version	uname -r
OS version	lsb_release -a
IP addresses	ip -br addr
Routing	ip route
DNS	resolvectl status
Listening ports	sudo ss -tulpn
Firewall	sudo nft list ruleset
Disk usage	df -h
Memory	free -h
CPU	lscpu
Running services	systemctl --type=service
Failed services	systemctl --failed
System logs	journalctl -xe
Docker containers	docker ps -a
GCP instances	gcloud compute instances list
GCP networks	gcloud compute networks list
GCP firewall	gcloud compute firewall-rules list

Final Thoughts

Ubuntu 26.04 LTS is an important upgrade for Linux infrastructure and cloud administrators.

The biggest takeaways are:

1. Linux kernel 7.0 and updated hardware support.
2. Modernized networking and TLS security.
3. systemd 259 and cgroup v2 requirements.
4. Docker 29 and updated container infrastructure.
5. Improved cloud-init automation.
6. GCP AMD64v3 compatibility requirements.
7. Stronger security and ARM64 support.

For GCP administrators, the priority should be validating existing Compute Engine workloads, reviewing N1 CPU compatibility, testing container workloads, and updating infrastructure automation.

Support lifecycle: Ubuntu 26.04 LTS receives standard security maintenance through April 2031, with extended maintenance available through Ubuntu Pro.

Official References

• Ubuntu 26.04 LTS Release Notes
• Ubuntu 26.04 Changes Since Ubuntu 25.10
• Ubuntu 26.04 Security Improvements
• Google Cloud Compute Engine Documentation
• Google Cloud gcloud CLI Documentation