Firewall

Common Problems 116564

Ubuntu 24.04 LTS – libvirt default network inactive and VMs have no connectivity – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 20 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 […]

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Common Problems 124108

Oracle Linux 10 – nmstate apply fails because route metric values are invalid – Fix & Prevention

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Oracle Linux 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 […]

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Common Problems 114549

Time Drift In Virtual Machines Affecting Kerberos And TLS

🟡 Medium   ⏱ 5–30 min  Last verified: 20 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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Common Problems 114050

RHEL 10 – nmstate apply fails because route metric values are invalid – Fix & Prevention

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: RHEL 10.0 RHEL 10.1 📖 ~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 […]

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Common Problems 117051

Ubuntu 22.04 LTS – Docker bridge networking broken after nftables changes – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 20 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 […]

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Common Problems 115548

RHEL 7 systemctl Cannot Reload Daemon After Unit Edit

🟡 Medium   ⏱ 5–30 min  Last verified: 20 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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Common Problems 117541

Ubuntu 20.04 LTS – UFW policy change blocks SSH and remote administration – Fix & Prevention

🔴 Critical   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Ubuntu 20.04 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 […]

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Common Problems 118046

Ubuntu 18.04 LTS – UFW policy change blocks SSH and remote administration – Fix & Prevention

🔴 Critical   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Ubuntu 18.04 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 […]

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Common Problems 115538

RHEL 7 firewalld Rich Rule Order Breaks DNAT

🟡 Medium   ⏱ 5–30 min  Last verified: 20 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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Common Problems 114040

RHEL 10 – bonded interface fails over poorly because miimon is not configured – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: RHEL 10.0 RHEL 10.1 📖 ~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 […]

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