Linux

Adding Logstash Filters To Improve Centralized Logging (Logstash Forwarder) — step-by-step Linux tutorial on Progressive Robot

Adding Logstash Filters To Improve Centralized Logging (Logstash Forwarder)

Logstash is a powerful tool for centralizing and analyzing logs, which can help to provide and overview of your environment, and to identify issues with your servers. One way to increase the effectiveness of your Logstash setup is to collect important application logs and structure the log data by employing filters, so the data can be readily analyzed and query-able. We will build our filters around “grok” patterns, that will parse the data in the logs into useful bits of information.

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How to Install and Use Skopeo for Container Image Management on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Install and Use Skopeo for Container Image Management on RHEL 9

Skopeo is a command-line tool for working with container images and container image registries without requiring a running container daemon or root privileges. While Docker requires docker pull to download an image locally before inspecting or copying it, Skopeo can copy images directly between registries, inspect image metadata without downloading the full image, and sign/verify […]

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AlmaLinux 8 — rshim — vulnerability — patch and remediation guide — diagnosis and fix on AlmaLinux 8

AlmaLinux 8 — rshim — vulnerability — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: AlmaLinux 8 📖 ~4 min read  •  Source: AlmaLinux ALSA ALBA-2021:4228 Upstream summary: For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section. Table of contents Symptom & Impact Environment & Reproduction Root Cause […]

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Oracle Linux 8 — gcc — security and stability fixes — required update — diagnosis and fix on Oracle Linux 8

Oracle Linux 8 — gcc — security and stability fixes — required update (ELSA-2020-1864)

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Oracle Linux 8 📖 ~4 min read  •  Source: ELSA advisory ELSA-2020-1864 Related CVEs: CVE-2019-15847 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance […]

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Common Problems 118437

Ubuntu 16.04 LTS cloud-init stalls first boot

🟡 Medium   ⏱ 5–30 min  Last verified: 19 May 2026 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs References & Further […]

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Gentoo Linux — games-board/gnuchess — vulnerability — patch and remediation guide — diagnosis and fix on Gentoo Linux

Gentoo Linux — games-board/gnuchess — vulnerability — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Gentoo Linux 📖 ~4 min read  •  Source: Gentoo GLSA GLSA-202107-28 Related CVEs: CVE-2021-30184 Upstream summary: The cmd_pgnload() and cmd_pgnreplay() functions in cmd.cc in GNU Chess to not sufficiently validate PGN file input, potentially resulting in a buffer overflow. Table of contents […]

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Gentoo Linux — media-gfx/openscad — vulnerability — patch and remediation guide — diagnosis and fix on Gentoo Linux

Gentoo Linux — media-gfx/openscad — vulnerability — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Gentoo Linux 📖 ~4 min read  •  Source: Gentoo GLSA GLSA-202107-35 Related CVEs: CVE-2020-28599 Upstream summary: A buffer overflow exists in OpenSCAD when parsing STL files. Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis […]

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Initial Server Setup with Ubuntu 12.04 — step-by-step Linux tutorial on Progressive Robot

Initial Server Setup with Ubuntu 12.04

This tutorial covers how to login with root, how to change the root password, how to create a new user, how to give the new user root privileges, how to change the port, and how to disable root login in. This tutorial is written for Ubuntu. When you first create your server, this tutorial explains the first steps you need to take. This tutorial is written for Ubuntu 12.04.

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