Technical Insights
Deep dives into network engineering, infrastructure architecture, security practices, and automation.
47 posts
AI and AIOps for Network Engineers: Anomaly Detection, LLM-Assisted Configs, and Predictive Operations
A practical guide to applying AI in network operations — covering AIOps pipelines for anomaly detection, using large language models for config generation and review, predictive capacity planning with Python, vendor AI platforms (Cisco AI Analytics, Juniper Mist, Aruba), and where human expertise remains irreplaceable.
Ansible for Network Automation: Playbooks, Roles, and IOS/NX-OS Configuration Management
Automate Cisco IOS, IOS-XE, and NX-OS configuration with Ansible — covering inventory, connection plugins, ios_config vs cli_command, idempotent playbooks, roles, Jinja2 templates, and a full VLAN deployment workflow.
AWS and Azure Hybrid Connectivity: VPN, Direct Connect, and ExpressRoute Design
Connect your on-premises network to AWS and Azure using IPsec VPN, AWS Direct Connect, and Azure ExpressRoute — covering BGP peering, route propagation, dual-provider redundancy, and real-world failover design for enterprise hybrid cloud.
Azure Cloud Networking Best Practices: VNet Design, NSGs, Azure Firewall, and Private Link
A network engineer's field guide to Azure cloud networking — covering hub-spoke VNet architecture, NSG rule evaluation, Azure Firewall vs NVA design decisions, User Defined Routes, Private Endpoints, DDoS Protection, and Network Watcher troubleshooting from enterprise deployments.
BFD Deep Dive: Fast Failure Detection for OSPF, BGP, EIGRP, and Static Routes
BFD (Bidirectional Forwarding Detection) delivers sub-second link failure detection independent of the routing protocol — covering BFD timers, echo mode, single-hop vs multi-hop, and integration with OSPF, BGP, EIGRP, and IP SLA on Cisco IOS and NX-OS.
BGP Security: RPKI, Route Filtering, and Prefix Hijack Prevention
Harden BGP against route hijacks and prefix leaks using RPKI origin validation, IRR-based prefix filters, BGPSEC concepts, max-prefix limits, and peer authentication — with Cisco IOS-XE and NX-OS configurations.
Cisco ACI Fundamentals: Tenants, EPGs, Contracts, and Day-2 Operations
A practical introduction to Cisco ACI — covering the logical object model (tenant, VRF, BD, EPG), contract/filter policy enforcement, L3Out external connectivity, fabric bring-up, and essential Day-2 verification and troubleshooting commands.
Cisco Firepower FTD: Access Control Policies, IPS Tuning, and Snort Rule Management
A practical guide to Cisco Firepower Threat Defense (FTD) — covering FMC-managed deployment, access control policy order of operations, intrusion policy tuning, Snort rule customization, SSL inspection, file policies, and real-world troubleshooting from enterprise multi-context firewall environments.
Cisco ISE & 802.1X: Wired Authentication, Policy Design, and Troubleshooting
Deploy 802.1X wired authentication with Cisco ISE — covering RADIUS policy sets, MAB fallback, downloadable ACLs, VLAN assignment, CoA, and systematic troubleshooting of the most common authentication failures.
DMVPN Phase 2 and Phase 3: Spoke-to-Spoke Tunnels, NHRP, and Routing Design
A deep dive into DMVPN Phase 2 vs Phase 3 — covering mGRE tunnel design, NHRP resolution, spoke-to-spoke shortcut tunnels, routing protocol selection, split-horizon issues, and production troubleshooting.
Building a Network Lab with EVE-NG: Cisco, Palo Alto, and VeloCloud Topologies
A step-by-step guide to building a professional network lab using EVE-NG Community and Pro — covering server requirements, EVE-NG installation, Cisco IOS/NX-OS image upload, Palo Alto VM-Series, VeloCloud VCE, lab topology design, network bridging to physical networks, and study topologies for CCNA, CCNP, and PCNSE.
EVPN Deep Dive: Route Types, MAC Mobility, Multi-Homing, and ARP Suppression
A detailed technical breakdown of EVPN route types 1–5, MAC/IP advertisement mechanics, VM live migration with MAC mobility, multi-homing with ESI, ARP suppression, and Type-5 IP prefix routes for symmetric IRB — with Cisco NX-OS verification.
HSRP, VRRP, and GLBP: First-Hop Redundancy Protocols Deep Dive
A comprehensive field guide to HSRP v2, VRRP, and GLBP — covering active/standby election, preemption, object tracking, timers, load balancing, and real-world troubleshooting from enterprise deployments.
IPv6 Enterprise Deployment: Dual-Stack, DHCPv6, SLAAC, and Migration Strategies
A practical engineer's guide to deploying IPv6 in enterprise networks — covering dual-stack design, prefix planning, DHCPv6 stateful/stateless, SLAAC with RDNSS, RA Guard, IPv6 ACLs, and phased migration from IPv4-only to full dual-stack.
MPLS Traffic Engineering: RSVP-TE Tunnels, Constraints, and Fast Reroute
Deploy MPLS-TE to steer traffic off congested paths and onto constrained routes — covering RSVP-TE signaling, TE tunnel configuration, autoroute, CSPF, bandwidth reservation, and Fast Reroute (FRR) for sub-50ms protection on Cisco IOS and IOS-XE.
NetFlow and IPFIX: Traffic Analysis, Anomaly Detection, and Collector Setup
Deploy NetFlow v9 and IPFIX on Cisco routers and switches to gain per-flow traffic visibility — covering flexible NetFlow templates, sampled vs unsampled collection, top-talker analysis, DDoS detection, and open-source collector setup with nfdump and ntopng.
Nornir: Python-Native Network Automation Without the Overhead
A practical guide to Nornir 3.x — the Python-native network automation framework. Covers inventory management with YAML, threaded task execution, plugin ecosystem (netmiko, napalm, scrapli), result handling, filtering, and real-world use cases including config compliance checking and mass config deployment.
P1 Incident Response Playbook: Leading a Critical Network Outage from Alert to RCA
A field-tested playbook for leading P1 network incidents — covering the full lifecycle from PagerDuty alert to war room coordination, real-time triage methodology, communication cadence, escalation decisions, live troubleshooting approach, restoration, and writing a post-incident RCA that actually prevents recurrence. Based on real Asia-Pacific MPLS core failure recovery.
PBR and IP SLA: Traffic Steering, Path Monitoring, and Conditional Routing
Master Policy-Based Routing and IP SLA to engineer deterministic traffic paths — covering ACL-based traffic classification, verify-availability, recursive next-hop tracking, multi-path load balancing, and production troubleshooting on Cisco IOS and IOS-XE.
PCI-DSS Network Compliance: CDE Segmentation, Firewall Rules, and Audit-Ready Configs
A network engineer's field guide to PCI-DSS compliance — covering CDE scoping and segmentation, firewall rule requirements (Requirement 1), access control (Requirements 7 and 8), encryption (Requirement 4), logging (Requirement 10), and how to achieve zero audit findings across enterprise sites.
SolarWinds NPM: Custom Alerts, Baselining, and ServiceNow/PagerDuty Integration
A practitioner's guide to SolarWinds NPM for enterprise networks — covering SNMP node management, interface and volume monitoring, custom alert thresholds, baseline trending, ServiceNow CMDB incident auto-creation, and PagerDuty webhook integration for 24/7 on-call rotation.
TACACS+ and AAA: Centralized Device Authentication with Cisco ISE
A complete guide to deploying TACACS+ for network device administration — covering AAA fundamentals, Cisco IOS AAA configuration, ISE TACACS+ policy sets, command authorization, privilege levels, accounting logs, and HA deployment with primary/secondary ISE nodes.
Cisco WS-C3750X-24T-S IOS Upgrade: 15.0(2)SE1 to 15.2(4)E10
Step-by-step guide for upgrading a Cisco Catalyst 3750X stack from IOS 15.0(2)SE1 to 15.2(4)E10 — covering pre-upgrade validation, image transfer, stack member sequencing, boot variable configuration, post-upgrade verification, and rollback procedure.
VMware VeloCloud SD-WAN: Best Practices and Troubleshooting Guide
A field-tested guide to VeloCloud SD-WAN deployment best practices, QoS optimization, tunnel troubleshooting, and resolving the most common issues in enterprise multi-site environments — with topology diagrams and CLI references.
EIGRP Best Practices: Design, Tuning, and Troubleshooting
A deep-dive into EIGRP design principles, DUAL algorithm behavior, metric tuning, neighborship troubleshooting, route summarization, stub routing, and hardening best practices for enterprise deployments.
F5 BIG-IP Load Balancer Best Practices: LTM, Pools, Profiles, and Troubleshooting
A comprehensive field guide to F5 BIG-IP Local Traffic Manager — covering virtual server design, pool and monitor configuration, persistence profiles, SSL offload, iRules, health monitor tuning, and systematic troubleshooting for enterprise load balancing environments.
GlobalProtect and Prisma Access Best Practices: Configuration and Troubleshooting
A comprehensive field guide to Palo Alto GlobalProtect VPN and Prisma Access — covering gateway and portal design, agent configuration, split tunneling, HIP profiles, authentication troubleshooting, tunnel diagnostics, and systematic debugging for enterprise remote access deployments.
MPLS L3VPN Best Practices: PE/CE Routing, VPNv4, and Troubleshooting
A deep-dive into MPLS L3VPN architecture, PE-CE routing protocol options, VPNv4 BGP design, route distinguishers, route targets, and systematic troubleshooting for service provider and enterprise MPLS deployments.
Network Automation with Python: Netmiko, NAPALM, and Config Auditing
A practical guide to automating network configuration and auditing using Python — covering Netmiko for SSH CLI automation, NAPALM for multi-vendor config management, parallel execution across device fleets, and building config compliance checks.
Nexus VDC and vPC Architecture: Design, Best Practices, and Troubleshooting
Complete guide to Cisco Nexus Virtual Device Contexts (VDC) and Virtual Port Channel (vPC) — covering VDC isolation design, resource allocation, vPC peer-link configuration, dual-active scenarios, orphan port handling, and deep CLI troubleshooting for NX-OS environments.
QoS Best Practices: DSCP Marking, Queuing, and Policing
A practical guide to enterprise QoS design — covering DSCP marking strategy, classification, queuing models, policing versus shaping, MQC configuration, and end-to-end QoS validation on Cisco platforms.
Cisco SD-WAN Best Practices: Design, Policy, and Troubleshooting
A comprehensive guide to Cisco Catalyst SD-WAN (Viptela) architecture, control plane design, traffic policies, application-aware routing, and systematic troubleshooting for enterprise WAN deployments.
Spanning Tree Best Practices: RSTP, MSTP, and Layer 2 Hardening
A comprehensive guide to Spanning Tree Protocol design — covering RSTP convergence, MSTP instance design, root bridge placement, PortFast, BPDU Guard, loop prevention, and Layer 2 hardening for enterprise campus networks.
Spine-Leaf Architecture Best Practices: Design, BGP Underlay, and Troubleshooting
Complete guide to spine-leaf (Clos) fabric design — topology principles, eBGP underlay, ECMP, VXLAN integration, leaf roles, scaling, and deep CLI troubleshooting scenarios including BGP failures, ECMP asymmetry, hardware FIB mismatches, and BFD tuning.
VRF Best Practices: Design, Segmentation, and Troubleshooting
A comprehensive guide to VRF design principles, route leaking, VRF-Lite deployment, MPLS VPN integration, and systematic troubleshooting for multi-tenant and enterprise network segmentation.
VXLAN Best Practices: Overlay Design, EVPN Control Plane, and Troubleshooting
A comprehensive guide to VXLAN overlay networking — covering VNI design, EVPN control plane with MP-BGP, BUM traffic handling, symmetric vs asymmetric IRB routing, multi-tenancy, and systematic troubleshooting for modern data center fabrics.
Zero Trust Network Segmentation: Microsegmentation and Palo Alto Policy Design
A practical guide to implementing Zero Trust network architecture — covering microsegmentation principles, identity-based policy design, Palo Alto NGFW zone segmentation, security policy best practices, and audit-ready compliance posture.
BGP Troubleshooting and Best Practices
A practical field guide for diagnosing BGP neighborship failures, route advertisement issues, and convergence problems — covering session states, path selection, route filtering, communities, and hardening best practices for enterprise and ISP deployments.
OSPF Troubleshooting and Best Practices
A comprehensive field guide for diagnosing OSPF adjacency failures, LSA propagation issues, route calculation problems, and area design mistakes — covering neighbor states, DR/BDR elections, route redistribution, and production hardening for enterprise networks.
SSL/TLS Certificate Management: Application, Renewal, and Troubleshooting Guide
A field guide to SSL/TLS certificate lifecycle management — covering certificate types, CSR generation, deployment on IIS/Apache/Nginx/Cisco devices, automated renewal with Let's Encrypt, and systematic troubleshooting of common certificate errors.
Automating Interface Documentation: Parsing Cisco IOS, ASA & Nexus Configs into a Hosts File
Stop manually documenting IP addresses. This Python script parses running configs from Cisco IOS, ASA, and Nexus devices and outputs a clean, aligned hosts-style file with interface aliases, CIDR notation, VIP detection, and crypto peer IPs — ready to drop into your IP documentation workflow.
Migrating from Cisco ASA to Palo Alto NGFW: A Step-by-Step Field Guide
A practical migration guide for replacing a Cisco ASA with a Palo Alto NGFW — covering policy translation, NAT migration, VPN cutover, interface mapping, security zone design, and how to validate without dropping production traffic.
Troubleshooting DMVPN Tunnels Between Sites on Specific VRFs
A step-by-step field guide for diagnosing DMVPN Phase 2/3 tunnel failures between spoke sites running inside a specific VRF — covering NHRP registration, spoke-to-spoke resolution, mGRE interface binding, VRF route leaking, and IPSec crypto map issues.
BGP Prepending, HSRP, PBR & IP SLA: Building a Bulletproof Failover Architecture
A practical field guide to combining BGP AS-path prepending, HSRP, Policy-Based Routing, and IP SLA to engineer deterministic, automatic failover across dual ISP links — with real Cisco configs.
Troubleshooting IPSec VPN Tunnels: Cisco ASA & Palo Alto Step-by-Step
A complete step-by-step troubleshooting playbook for IPSec site-to-site VPN tunnels on Cisco ASA and Palo Alto NGFW — covering Phase 1 IKE failures, Phase 2 mismatches, crypto ACLs, NAT exemptions, and packet captures.
BGP Route Filtering Best Practices for Enterprise Networks
A deep dive into BGP route filtering strategies that prevent route leaks, ensure stability, and protect your AS from external instability.
Automating Network Configuration with Python and Netmiko
How I used Python and Netmiko to automate configuration deployments across 200+ devices, reducing deployment time from hours to minutes.