Network Troubleshooting Lab

This repository contains practical network and infrastructure troubleshooting scenarios based on operational incidents commonly encountered in cloud-native and telecommunications environments.

The objective of this repository is to demonstrate a structured troubleshooting methodology including impact assessment, technical investigation, root cause analysis, corrective actions, and service recovery validation.

Scenarios

Scenario	Description
BGP Neighbor Down	Investigation of routing peer failures and route exchange issues
Gateway Unavailable	Analysis of service accessibility and traffic forwarding problems
ECFE Configuration Synchronization	Investigation of configuration mismatch and synchronization failures
High Root Disk Utilization	Analysis of filesystem capacity and storage consumption issues
OAM Application Restart Investigation	Kubernetes application restart and resource analysis
Connectivity Testing Methodology	Structured approach for isolating communication failures

Skills Demonstrated

Networking

• BGP Troubleshooting
• Route Validation
• Network Reachability Analysis
• Traffic Flow Verification
• Gateway Investigation
• Connectivity Testing

Kubernetes

• Pod Investigation
• Service Troubleshooting
• Endpoint Verification
• Resource Analysis
• Event Analysis
• Log Analysis

Linux Administration

• Filesystem Analysis
• Process Investigation
• Service Validation
• Resource Monitoring
• Log Management

Operational Support

• Root Cause Analysis
• Incident Investigation
• Service Recovery
• Alarm Analysis
• Change Verification
• Troubleshooting Methodology

Troubleshooting Framework

Each scenario follows a structured investigation process:

1. Incident Summary
2. Impact Assessment
3. Initial Investigation
4. Technical Analysis
5. Root Cause Analysis
6. Corrective Actions
7. Verification
8. Lessons Learned

Investigation Methodology

Alarm / Incident
       │
       ▼
Impact Assessment
       │
       ▼
Initial Investigation
       │
       ▼
Technical Analysis
       │
       ▼
Root Cause Analysis
       │
       ▼
Corrective Actions
       │
       ▼
Verification
       │
       ▼
Incident Closure

This methodology is used throughout the repository to ensure a consistent and structured troubleshooting approach.

Repository Structure

network-troubleshooting-lab/
│
├── README.md
│
├── bgp-neighbor-down/
│   └── README.md
│
├── gateway-unavailable/
│   └── README.md
│
├── ecfe-config-stale/
│   └── README.md
│
├── high-root-disk-utilization/
│   └── README.md
│
├── oam-killer-investigation/
│   └── README.md
│
└── connectivity-testing/
    └── README.md

Key Investigation Areas

The repository focuses on practical troubleshooting techniques including:

• Network connectivity validation
• Routing analysis
• Configuration verification
• Resource utilization analysis
• Application health investigation
• Alarm correlation
• Service recovery validation

Disclaimer

All examples are based on lab environments and personal learning exercises. No customer, production, confidential, or proprietary information is included in this repository.