Firewall

pr cp 127687 r2

CentOS Stream 9 – Common Problem 198 – Diagnosis and Fix

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: CentOS Stream 9 📖 ~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
pr cp 120682 r2

Debian 11 – Fail2ban Not Banning with nftables Backend – Jail Action Fix

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Debian 11 📖 ~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
pr cp 115109 r2

RHEL 8 – Postfix Mail Queue Stalls from DNS Resolver Problems

🟡 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 […]

Read more
pr cp 121181 r2

Debian 10 – Fail2ban Not Banning with nftables Backend – Jail Action Fix

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Debian 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
pr cp 117110 r2

Ubuntu 22.04 LTS Fail2ban Not Banning Attackers Due to Journal Backend Misconfig

🟡 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 […]

Read more
pr cp 121681 r2

Debian 9 – Fail2ban Not Banning with nftables Backend – Jail Action Fix

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Debian 9 📖 ~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
pr cp 120172 r2

Debian 12 – Fail2ban Not Banning with nftables Backend – Jail Action Fix

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Debian 12 📖 ~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
pr cp 115099 r2

RHEL 8 – rsyslog Forwarding Stops Sending to SIEM

🟡 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 […]

Read more
pr cp 120672 r2

Debian 11 – KVM Bridge Networking Stops Passing Traffic – Host Bridge Repair

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Debian 11 📖 ~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
pr cp 121171 r2

Debian 10 – KVM Bridge Networking Stops Passing Traffic – Host Bridge Repair

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Debian 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
CHAT