Ubuntu on Support Tools

Plex Media Server CVE-2026-96656 (CISA KEV): Check, Investigate and Patch

Tue, 27 Oct 2026 09:00:00 -0500

On 2026-10-20, CISA added four Plex Media Server vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog: CVE-2026-96656, CVE-2026-96654, CVE-2026-96655 and CVE-2026-96652. A fifth bug from the same advisory, CVE-2026-96651, is not in KEV, but it is the piece that turns an “admin only” code execution bug into something a regular session holder can reach. All five are fixed in Plex Media Server 1.43.3.10861. If your home media server is older than that, it needs attention today.

This guide is for self-hosters running Plex on Debian or Ubuntu (with a short section for Docker). It covers three questions in order: am I vulnerable, was I compromised, and how do I patch. It also covers the apt signing key gotcha that leaves many servers silently stuck on old builds after an Ubuntu release upgrade.

Four Places PHP Was Hiding: Patching PHP2Shell (CVE-2026-109618/109619) Across the Fleet

Fri, 23 Oct 2026 09:00:00 -0500

On 2026-10-21 the PHP project shipped an out-of-band release fixing a pair of vulnerabilities that quickly got the nickname “PHP2Shell”: CVE-2026-109618 and CVE-2026-109619, CVSS 9.2, unauthenticated remote code execution. Both are use-after-free bugs (CWE-416). One is an out-of-bounds, out-of-memory corruption during multipart request parsing. The other is stale per-request state that gets reused across php-fpm and mod_php workers. Either one lets an unauthenticated attacker who can reach a PHP endpoint corrupt memory in a way that leads to code execution. The fixed versions are PHP 8.5.12, 8.4.27, 8.3.36, and 8.2.35.

The boring read of that advisory is “run apt upgrade and move on.” The interesting part, and the reason this post exists, is that when we went looking for PHP across the fleet, it was hiding in four very different places. A distro package on a mail server. A compiled-from-source binary inside a container image. The web GUI of a pair of firewalls. And the web GUI of a single edge firewall on an older release train. Each of those needed a genuinely different remediation, and each one had a trap that would have let us declare victory while still running a vulnerable interpreter.

This is the write-up of how we found all of it, how we proved each box was actually fixed rather than trusting a version string, and the HA dance that let us patch a production firewall pair with zero WAN outage.

Mount Windows/Samba Shares on Ubuntu/Debian 2025: Complete CIFS Network Storage Guide

Wed, 22 Oct 2025 10:00:00 -0500

Mounting Windows/Samba shares on Ubuntu and Debian systems enables seamless access to network storage, file servers, and NAS devices. This comprehensive guide covers CIFS/SMB configuration, persistent mounting, Active Directory integration, and enterprise-grade network storage management techniques.

USB to RS232 Serial Converter Setup Guide 2025: Ubuntu/Debian Console Access & Device Management

Sun, 05 Oct 2025 10:00:00 -0500

USB to RS232 serial converters provide essential console access to network equipment, embedded systems, and legacy hardware. This comprehensive guide covers device detection, driver configuration, serial communication setup, and advanced troubleshooting techniques for Ubuntu and Debian systems.

Dell iDRAC Tools & RACADM Installation Guide 2025: Ubuntu/Debian PowerEdge Server Management

Tue, 02 Sep 2025 10:00:00 -0500

Dell’s Integrated Dell Remote Access Controller (iDRAC) provides powerful out-of-band management capabilities for PowerEdge servers. While Dell only officially supports RHEL and SUSE distributions, this guide demonstrates how to successfully install and utilize iDRAC tools, particularly RACADM, on Ubuntu and Debian systems through RPM-to-DEB conversion.

Enterprise Linux Swap and Memory Management: Comprehensive Performance Optimization and Infrastructure Automation

Tue, 29 Jul 2025 10:00:00 -0500

Enterprise Linux environments require sophisticated swap and memory management strategies to ensure optimal performance, prevent out-of-memory conditions, and maintain system stability across thousands of servers running mission-critical workloads. This guide covers advanced swap configuration, enterprise memory optimization frameworks, automated performance tuning, and comprehensive monitoring solutions for production infrastructures.

Enterprise Netplan Network Automation: Comprehensive Infrastructure as Code for Production Network Management

Tue, 22 Jul 2025 10:00:00 -0500

Enterprise network infrastructure requires sophisticated automation frameworks, declarative configuration management, and comprehensive orchestration systems to ensure consistent, reliable, and scalable network deployments across thousands of systems. This guide covers advanced Netplan implementations, enterprise network automation architectures, production configuration management, and comprehensive infrastructure as code strategies for modern data centers.

Mount FTP Sites as Local Folders in Linux 2025: Complete curlftpfs & FUSE Integration Guide

Fri, 18 Jul 2025 10:00:00 -0500

Mounting FTP sites as local directories transforms remote file management by integrating FTP servers seamlessly into your Linux filesystem. This comprehensive guide covers curlftpfs installation, advanced mounting techniques, security best practices, performance optimization, and enterprise-scale FTP storage integration.

ISO Creation, Burning & Bootable USB Guide 2025: Complete Linux Media Management

Mon, 14 Jul 2025 10:00:00 -0500

Creating ISO images, burning optical media, and crafting bootable USB drives are essential skills for system administrators, developers, and IT professionals. This comprehensive guide covers modern media creation techniques, enterprise deployment strategies, and advanced disk imaging workflows for Linux systems.

Enterprise Ubuntu Repository GPG Key Management: Comprehensive Security Infrastructure and Automated Package Trust Framework

Tue, 08 Jul 2025 10:00:00 -0500

Enterprise Ubuntu repository management requires sophisticated GPG key infrastructure, automated trust validation systems, and comprehensive security frameworks to ensure package integrity across thousands of systems while maintaining supply chain security. This guide covers advanced repository key management, enterprise package security architectures, automated trust validation systems, and production-grade APT repository infrastructures.

Enterprise Ubuntu on Raspberry Pi: Comprehensive Edge Computing Deployment and Automation Framework for Production IoT Infrastructure

Tue, 24 Jun 2025 10:00:00 -0500

Enterprise edge computing deployments on Raspberry Pi require sophisticated automation frameworks, robust fleet management systems, and comprehensive infrastructure orchestration to deliver reliable IoT solutions at scale. This guide covers advanced Ubuntu deployment strategies on ARM devices, enterprise-grade edge computing architectures, automated provisioning systems, and production fleet management for thousands of edge nodes.

Create an Encrypted ZFS Pool on Linux (Native Encryption)

Sun, 16 Feb 2025 01:00:00 -0500

This guide creates a ZFS pool with OpenZFS native encryption on Linux, unlocks it automatically at boot from a key file, and covers the tuning, monitoring and backup steps that matter once the pool holds real data.

Complete Guide: Install Kubernetes Cluster on Ubuntu with Kubeadm and Swap Support

Fri, 14 Feb 2025 02:00:00 -0500

Setting up a Kubernetes cluster can be complex, but kubeadm simplifies the process significantly. This comprehensive guide walks you through installing a production-ready Kubernetes cluster on Ubuntu, with advanced features like swap support, CgroupV2 configuration, and containerd setup. Whether you’re building a development environment or preparing for production deployment, this guide provides all the necessary steps and best practices.

How to Set Up Promtail in Ubuntu 20.04

Wed, 11 Dec 2024 12:00:00 -0500

How to Set Up Promtail in Ubuntu 20.04

Promtail is an essential tool for shipping logs from your applications to a Loki instance. When integrated with Grafana, it enables seamless log aggregation and monitoring. This guide walks you through installing and configuring Promtail on Ubuntu 20.04.

Prerequisites

Loki and Grafana are already configured.
A running application to monitor (e.g., NGINX in this example).

Step 1: Install Promtail

Check Your CPU Architecture:
bash
```
uname -a
```

Download the Promtail Binary: Replace amd64 with your system’s architecture if different.

bash
curl -O -L "https://github.com/grafana/loki/releases/download/v2.4.1/promtail-linux-amd64.zip"

Extract and Make Executable:

bash
unzip "promtail-linux-amd64.zip"
chmod a+x "promtail-linux-amd64"

Move Binary to System Path:

bash
sudo cp promtail-linux-amd64 /usr/local/bin/promtail

Verify Installation:
bash
```
promtail --version
```

Get Rid of Ubuntu Pro Advertisement When Updating Apt

Sat, 07 Sep 2024 19:26:00 -0500

If you’re using Ubuntu and have recently noticed the promotional message for Ubuntu Pro while updating your system with apt, you’re not alone. While Ubuntu Pro is useful for certain users, many prefer a clean update process without ads. In this guide, we’ll cover how to disable those Ubuntu Pro advertisements.

Fix sshd: no hostkeys available -- exiting (WSL, Ubuntu)

Sun, 30 Jun 2024 23:18:00 -0500

sshd: no hostkeys available -- exiting. is printed when the OpenSSH server starts and cannot load a single host key from /etc/ssh. The fix is one command, sudo ssh-keygen -A, which creates every missing host key type. This guide shows the exact output before and after, why WSL and container images ship without keys, the other two causes that print the same line (bad permissions and a wrong HostKey path), and what clients see after the keys change.

Increasing max_user_watches for Large Workspaces in Visual Studio Code

Wed, 22 May 2024 12:45:00 -0500

Learn how to increase the max_user_watches value on Ubuntu to handle large workspaces in Visual Studio Code. This guide will help you resolve file-watching issues in VS Code.

Installing k3s on Ubuntu on Raspberry Pi

Sat, 18 May 2024 19:26:00 -0500

Learn how to install k3s on Ubuntu running on Raspberry Pi, including setup for control plane and agents. Follow this guide for a smooth installation process.

Fix 'sudo: unable to resolve host' on Ubuntu (/etc/hosts)

Tue, 14 May 2024 02:24:00 -0500

Learn how to quickly fix the common ‘sudo: unable to resolve host’ error in Ubuntu by properly configuring your /etc/hosts file. This guide provides a detailed step-by-step solution.

How to Disable IPv6 on Ubuntu: A Step-by-Step Guide

Sun, 18 Feb 2024 00:29:19 -0600

IPv6 is the future of networking, but there are many scenarios where disabling it on Ubuntu servers might be necessary. Whether you’re troubleshooting network issues, improving security, or ensuring compatibility with legacy applications, turning off IPv6 can be beneficial.

Add a CA Certificate to Ubuntu: update-ca-certificates

Thu, 12 Oct 2023 23:18:00 -0500

To trust a private or self-signed certificate authority on Ubuntu, put the CA certificate in /usr/local/share/ca-certificates/ with a .crt extension and run sudo update-ca-certificates. That rebuilds /etc/ssl/certs/ca-certificates.crt, the bundle that curl, wget, git, apt, OpenSSL and most other tools on Ubuntu read. The procedure is identical on Ubuntu 22.04, 24.04 and 26.04. This guide covers getting the right certificate, the expected output, the three mistakes that make it silently do nothing, and the applications that ignore the system store.

Resize a Root ext4 Partition Online Without Reboot

Thu, 14 Jul 2022 14:05:00 -0500

The following is a guide to resizing your root ext4 file system online. After the operation, your partition will have more free space. There will be no shrinkage of the root file system. The root partition could have been any partition, not exactly the root one, but in most cases, such operations on the root are more complex and dangerous, so ALWAYS back up (or snapshot the VM) before performing such operations!

During the resize operation, none of the services need to be shut down, rebooted, or unmounted.

Even so, we rebooted the server once as a precaution, since it was possible and the server was not in production. Rebooting the server after this kind of resizing is not necessary. The method was tested on Ubuntu 22.04 with kernel 5.15 on a VMware virtual disk. Any distribution with a recent kernel, parted (or growpart) and e2fsprogs works the same way.

Summary:

Make the kernel see the larger disk (rescan the SCSI device).
Grow the partition with growpart (package cloud-guest-utils on Debian and Ubuntu, cloud-utils-growpart on RHEL) or with resizepart in parted.
Grow the file system using resize2fs from E2fsprogs. There is a version of this package included in most Linux distributions with the same name.

cachefilesd Setup: Cache NFS Mounts With FS-Cache (fsc)

Mon, 11 Jul 2022 23:24:00 -0500

cachefilesd is the userspace daemon for CacheFiles, the Linux kernel’s disk cache backend for FS-Cache. With it running, NFS (and AFS) mounts that use the fsc mount option keep a copy of the data they read on local disk, so the second read of a file comes from the cache instead of the network. Setup is four steps: install the package, enable it (on Debian and Ubuntu that means RUN=yes), start the daemon, and remount the NFS share with fsc. This guide shows each step on Ubuntu 24.04 and 26.04, how to prove the cache is in use, and when it does not help.

How to Install Google Chrome on Ubuntu Desktop

Mon, 11 Jul 2022 19:26:00 -0500

Google Chrome is a popular web browser developed by Google. In this guide, we will show you how to install Google Chrome on your Ubuntu desktop.

kernel: rc rc0: receive overflow

Thu, 23 Jun 2022 23:52:00 -0500

After upgrade my build nodes from Ubuntu 20.04 to Ubuntu 22.04, I got a lot of spamming syslog messages on my Intel NUC nodes, model NUC5i5RYB. Both these nodes are running RKE2 v1.24.1+rke2r2. I have them tainted so that they are only used by Drone CI to run Kubernetes runners.

Error message

Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.557663] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.561258] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.566120] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.569739] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.618179] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.637622] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.645784] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.649311] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.656808] rc rc0: receive overflow
Jun 24 04:35:27 a0ubnucp02 kernel: [ 2025.660897] rc rc0: receive overflow

How to disable systemd-resolved in Ubuntu

Mon, 01 Mar 2021 01:14:00 +0000

systemd-resolved can cause issues with Kubernetes (not to mention the time spent troubleshooting various issues).

How to Fix 'rm: cannot remove '/etc/resolv.conf': Operation not permitted'

Wed, 09 Dec 2020 20:47:00 +0000

In Ubuntu, you may run into an issue when updating /etc/resolv.conf even tho you have root permissions.

Error:

rm: cannot remove '/etc/resolv.conf': Operation not permitted

How to Fix 'E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable)'

Thu, 22 Oct 2020 10:52:00 +0000

In Ubuntu, you may sometimes encounter an error when attempting to run an apt command:

E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable)
E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?

Install PowerShell on Ubuntu

Wed, 20 Nov 2019 11:06:00 +0000

As part of my DevOps process, I needed to create some DNS records on my Windows DNS server. In order to script this out, I needed to install PowerShell on my Jenkins server which is running Ubuntu 18.04.