Troubleshooting

Windows Server 2012 R2 — DNS scavenging removes active records due to aging configuration drift in AD-integrated zones — Fix & Prevention

• February 13, 2021
• Tutorials
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🟠 High   ⏱ 5–30 min  Last verified: 13 February 2021 Affected versions: Windows Server 2012 R2 📖 ~2 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 […]

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IBM AIX 7.1 — CVE-2021-38976 — vulnerability — patch and remediation guide

• February 13, 2021
• Tutorials
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🟡 Medium   ⏱ 15–45 min  Last verified: 13 February 2021 Affected versions: IBM AIX 7.1 📖 ~4 min read  •  Source: NVD CVE-2021-38976, IBM Support Bulletin CVE: CVE-2021-38976 NVD summary: IBM Tivoli Key Lifecycle Manager 3.0, 3.0.1, 4.0, and 4.1 stores user credentials in plain clear text which can be read by a local […]

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How to Set Up a DNS Server with BIND9 on RHEL 7

• February 13, 2021
• Linux
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How to Set Up a DNS Server with BIND9 on RHEL 7 The Berkeley Internet Name Domain (BIND) is the most widely deployed DNS server software in the world, and BIND 9 is the version available in the RHEL 7 package repositories. Setting up your own DNS server gives you authoritative control over a domain […]

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Gentoo Linux — media-libs/libexif — multiple vulnerabilities (10 CVEs) — patch and remediation guide

• February 13, 2021
• Linux
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🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Gentoo Linux 📖 ~4 min read  •  Source: Gentoo GLSA GLSA-202011-19 Related CVEs: CVE-2020-0181 CVE-2020-0198 CVE-2020-0452 CVE-2016-6328 CVE-2019-9278 CVE-2020-0093 CVE-2020-12767 CVE-2020-13112  +2 more Upstream summary: Multiple vulnerabilities have been discovered in libexif. Please review the CVE identifiers referenced below for details. Table […]

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Oracle Linux 8 — Unbreakable Enterprise kernel — vulnerability — patch and remediation guide (ELSA-2021-9114)

• February 13, 2021
• Linux
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🟠 High   ⏱ 15–60 min  Last verified: 13 February 2021 Affected versions: Oracle Linux 8 📖 ~4 min read  •  Source: ELSA advisory ELSA-2021-9114 Related CVEs: CVE-2021-27364 CVE-2021-27365 CVE-2021-27363 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification […]

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How to Configure nftables Firewall on RHEL 7

• February 13, 2021
• Linux
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How to Configure nftables Firewall on RHEL 7 nftables is the modern successor to iptables, combining the functionality of iptables, ip6tables, arptables, and ebtables into a single, unified framework with a cleaner syntax, better performance, and native support for atomic rule replacement. While firewalld is the default front end on RHEL 7, nftables is available […]

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Oracle Linux 8 — ( aarch64 ) Some GUI Elements Aren’t Displayed During Installation and Boot Using VGA Output

• February 12, 2021
• Linux
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🟠 High   ⏱ 5–30 min  Last verified: 12 February 2021 Affected versions: Oracle Linux 8 📖 ~4 min read  •  Source: Oracle Bug 35270637 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 […]

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Alpine Linux edge — newsboat — vulnerability — patch and remediation guide

• February 12, 2021
• Linux
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🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Alpine Linux edge / fixed in 2.30.1-r0 📖 ~4 min read  •  Source: Alpine secdb entry — newsboat 2.30.1-r0 Related CVEs: CVE-2020-26235 Upstream summary: Alpine community repository for vedge ships newsboat 2.30.1-r0 which addresses CVE-2020-26235. Table of contents Symptom & Impact Environment […]

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Ubuntu 16.04 LTS initramfs BusyBox unable to mount root filesystem

• February 12, 2021
• Linux
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🟡 Medium   ⏱ 5–30 min  Last verified: 12 February 2021 📖 ~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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Windows Server 2016 – Failover cluster node enters repeated quarantine loop – Fix & Prevention

• February 12, 2021
• Tutorials
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🟠 High   ⏱ 5–30 min  Last verified: 12 February 2021 Affected versions: Windows Server 2016 📖 ~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 […]

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