Linux

Common Problems 116425

Ubuntu 24.04 LTS – netplan apply fails and network stays down – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 24.04 LTS 📖 ~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 […]

Read more
Debian 11 — tomcat9 — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Debian 11

Debian 11 — tomcat9 — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: Debian 11 (bullseye) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2019-0199 CVE-2019-0221 CVE-2019-10072 CVE-2019-12418 CVE-2019-17563 CVE-2019-17569 CVE-2020-11996 CVE-2020-13934  +12 more Upstream summary: The HTTP/2 implementation in Apache Tomcat 9.0.0.M1 to 9.0.14 and 8.5.0 to 8.5.37 accepted streams with […]

Read more
Common Problems 113927

RHEL 10 – firewalld rich rule disappears after reload – Fix & Prevention

🟡 Medium   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: RHEL 10 📖 ~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 & […]

Read more
Common Problems 116923

Ubuntu 22.04 LTS – DNS resolution fails with systemd-resolved stub issues – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 22.04 LTS 📖 ~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 […]

Read more
Common Problems 127001

CentOS Stream 10 – Common Problem 204 – Diagnosis and Fix

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: CentOS Stream 10 📖 ~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 […]

Read more
Common Problems 118946

Ubuntu 14.04 LTS – DNS resolution intermittently fails on servers – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 14.04 LTS 📖 ~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 […]

Read more
Common Problems 114921

RHEL 8 SELinux Denying httpd Access to Custom Content Path

🟡 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 […]

Read more
Common Problems 115924

Ubuntu 26.04 LTS – netplan apply fails with invalid YAML and drops networking – Fix & Prevention

🔴 Critical   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 26.04 LTS 📖 ~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 […]

Read more
Common Problems 118936

Ubuntu 14.04 LTS – boot drops to initramfs after unclean shutdown – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 14.04 LTS 📖 ~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 […]

Read more
Common Problems 114911

RHEL 8 firewalld Blocking Application Port Despite Service Running

🟡 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 […]

Read more
CHAT