Career
BGP Route Flap: The Cost of Stability in Scalable Networks
I explore BGP route flap issues, their impact on network stability, and how I've managed such incidents in my own operations, drawing from my experiences.
#network
100 posts found.
Technology
Zero-Trust Architecture: A Pragmatic Roadmap for Small Teams
A step-by-step guide on how small teams can practically and effectively implement zero-trust architecture. Core principles, tools...
Technology
Switch Hardening: Always a Necessary Step?
We delve deep into switch hardening, a cornerstone of network security. When is it necessary, what are the trade-offs, and its practical applications.
Tutorials
BGP Route Flap Anatomy: Why It Happens, How to Fix It?
Understand the root causes of BGP route flap issues, diagnose them, and ensure your network's stability with effective solutions.
Life
Why VLAN Segmentation is No Longer as Necessary? (Or Is It?)
With 20 years of system and network experience, I examine why VLAN segmentation is no longer as essential as it used to be, in a practical and direct manner...
Tutorials
The Anatomy of VLAN Segmentation: Foundations of Proper Design
Learn step-by-step how to design VLAN segmentation to improve network security and performance. Real-world scenarios and practical tips.
Tutorials
BGP Route Flap Damping: A Solution or a New Problem?
Deep dive into the BGP route flap damping mechanism. Explore its actual benefits, potential drawbacks, and real-world implications in network engineering.
Technology
Why is Network Switch Hardening Often Neglected?
I examine why network switch hardening is often overlooked, drawing from my real-world field experience. Closing security vulnerabilities...
Career
Why is BGP Route Flap Management Only Easy in Theory?
I explain the fundamentals, causes, and practical solutions for BGP route flap issues based on my own experiences. Why theoretical solutions are challenging in.
Tutorials
BGP Route Flap Management: Effective Prevention in 3 Steps
A practical guide to understanding, diagnosing, and effectively managing BGP route flap issues in 3 steps.
Technology
VLAN Segmentation: Balancing Security and Performance
I explain how I strike a balance between performance and security when moving from a flat network to VLAN segmentation, sharing technical details from my field.
Tutorials
Docker Container Network Traffic: Monitoring and Optimization on My
I'm detailing step-by-step how I monitor and optimize network traffic for Docker containers running on my VPS. Performance tips and practical commands included.
Tutorials
The Network's Blind Spot: Chasing MTU Mismatches
Discover the MTU mismatch behind mysterious issues affecting your network performance. In this detailed guide, learn what MTU is, how to diagnose problems, and…
Career
The Mysterious Effect of Clock Drift in Distributed Systems
Learn the causes, effects of clock drift in distributed systems and the methods used to solve it through a detailed examination.
Tutorials
Hunting Hidden Blackholes in Production Networks: An Anatomy of…
Find the invisible blackholes in your production network. Understand why traffic disappears, and walk through how to debug it step by step.
Life
Hidden IP Conflicts in Production: The Invisible Network War
Take a detailed look at the causes, consequences, and remedies for the hard-to-detect hidden IP conflicts that pop up in production environments.
Tutorials
How a Hidden DNS Bug Brought Down a Network Architecture: A Case Study
Learn through a case study how a hidden DNS bug threatening network architectures can spiral into a full-blown disaster. Don't miss this deep dive.
Technology
Syslog on Network Devices: TLS, Buffering, and Log Storm
A model for turning syslog loss and log storm risk into a reliable log channel for incident/audit, using TLS/relay, disk-backed queue, and rate limiting.
Technology
Protecting Router & Switch Control Plane with CoPP/CPP…
A CoPP/CPP model that classifies and polices routing, management, and ICMP traffic on the router/switch control plane to reduce CPU exhaustion and adjacency…
Technology
Hunting Silent Packet Loss During MLAG Failover
A signal set, failover testing playbook, and operational decision tree for tracking down silent packet loss in MLAG and LACP topologies.
Technology
OSPF/IS-IS Authentication: Block Rogue Neighbors in the Routing Domain
Reducing the risk of rogue neighbors and route injection in the routing domain through OSPF/IS-IS authentication, key rotation, and control-plane hardening.
Tutorials
Reducing Layer-2 Insider Threats on Switches with DHCP Snooping + DAI
A staged playbook for rolling out DHCP Snooping, DAI, and IP Source Guard on access networks to defend against rogue DHCP, ARP spoofing, and IP impersonation.
Tutorials
Secure Network Device Monitoring with SNMPv3: Auth, Encryption, ACL
A guide to leaving SNMPv2c community strings behind and making network device monitoring secure and operable with SNMPv3 authPriv, views and ACLs.
Technology
BMC (iDRAC/iLO/IPMI) Hardening and Management Segmentation
An operating model for the BMC (iDRAC/iLO/IPMI) attack surface using segmentation, identity, audit, and break-glass to keep it secure and auditable.
Technology
DoH/DoT/DoQ in Enterprise Networks: Policy and Visibility
A controlled-transition, telemetry, and runbook approach for enterprise policy and visibility in a world of encrypted DNS via DoH/DoT/DoQ.
Tutorials
IPv6-Only Migration with NAT64/DNS64: Runbook and Design
Design, risks, monitoring, and a practical runbook for managing IPv6-only clients' IPv4 dependencies using DNS64 + NAT64.
Technology
Edge Service Design with BGP Anycast: DNS and DDoS Resilience
A practical edge design guide that addresses routing, health signals, capacity, and attack scenarios together to see Anycast's real benefits.
Technology
Preventing Edge Outages with BGP Max-Prefix Limits
Designing, monitoring, and writing an incident runbook for the max-prefix guardrail that protects edge routers during route leaks and bad-prefix waves.
Technology
DDoS Scrubbing Center Design: GRE, BGP, and Failover
GRE tunnels, BGP signaling, capacity, and an operational runbook to keep the service up by diverting traffic to scrubbing during an attack.
Technology
Enterprise DNS Firewall with DNS RPZ: Threat Blocking and Operations
Build a sustainable DNS security control by blocking threat domains via RPZ at the recursive resolver, with proper exception handling and observability.
Technology
Load Balancer, Keepalive, and Retry Budgets for gRPC/HTTP2 Traffic
A practical architecture and operations guide for handling long-lived HTTP/2 connections, idle timeouts, and retry storms without losing your SLO.
Technology
Network Telemetry with IPFIX/NetFlow: A Pipeline for DDoS and Capacity
Build an operational telemetry pipeline by collecting and enriching IPFIX/NetFlow streams for DDoS triage, capacity planning, and anomaly detection.
Technology
BGP Traffic Engineering Runbook for the Enterprise Edge
A practical runbook for steering traffic with localpref, community, prepend, and MED in multi-ISP and multi-POP environments — measurable and reversible.
Technology
MTU and PMTUD Blackhole: An Incident Runbook
When some users work and others don't, a frequent cause is broken PMTUD and an MTU blackhole. Diagnosis steps and a permanent fix.
Technology
Path Selection and Incident Triage with SLA Probes in SD-WAN
Choosing the right path for application classes via active probes that measure latency/jitter/loss; rapid diagnosis during degradation and a controlled…
Technology
Egress Control in ZTNA: Designing Against Data Exfiltration
ZTNA isn't just about inbound access. A practical approach to data leakage with egress (outbound) control, DLP signals and service-centric segmentation.
Tutorials
Linux SoftIRQ Saturation and IRQ Affinity Runbook
Quick triage, measurement and safe tuning steps (ring, queue, IRQ, RPS) under packet drops, high softirq load and ksoftirqd pressure.
Tutorials
Packet Capture in Production with tcpdump: A Runbook
Practical tcpdump techniques for collecting minimal-yet-sufficient packet evidence during incidents: filters, snaplen, ring buffer, privacy, and handover…
Technology
Route Analytics with BGP BMP: Visibility and Incident Triage
Bring route leak, flap, and blackhole events down to minutes by combining BMP telemetry, route analytics, and an alarm model in a practical approach.
Technology
Firewall Rulebase Cleanup: Waves with Hitcount and Shadow Rules
Pull your firewall rule set out of the 'don't touch it, it'll explode' state with hitcount, log evidence, ownership, and a wave-based approach to safely…
Technology
Segmentation and Governance with Transit Gateway in Hybrid Cloud
A practical architecture guide that handles hub-spoke and Transit Gateway design together with security, route control, and operational observability.
Technology
Time Synchronization in Critical Systems: NTP, PTP and Observability
An architectural, security-focused, and operational view of NTP/PTP for distributed systems where TLS, log correlation, and consistency depend on accurate time.
Technology
From Pilot to Production: 802.1X (NAC) in Enterprise Networks
A field-tested approach to taking 802.1X from pilot to production: identity, policy, exceptions, and the runbook that turns it into a living control plane.
Technology
L2 Encryption with MACsec in Enterprise Networks
Hardening campus and data center backbones by encrypting L2 links with MACsec (802.1AE): design choices, risks, and operations.
Technology
Health Check Blindness in L4 Pools: Failover and Blackholes
When pool members appear 'UP' but traffic vanishes, combining active checks with passive signals to design failover that actually reflects reality.
Technology
QUIC / HTTP/3: Security and Operations on Enterprise Networks
A practical approach to managing HTTP/3 traffic over UDP/443 without breaking security, visibility, or performance.
Technology
Trust Boundary at the SD-WAN Edge: Egress Policy, DNS, and Logging
Preserving the trust boundary across DIA / DC / cloud egress in SD-WAN: traffic classification, DNS strategy, split-tunnel, and a centralized log model.
Tutorials
A Safe Migration Runbook from iptables to nftables
Reduce risk while moving production firewall rule sets from iptables to nftables using observability, wave-based rollout, and fast rollback.
Tutorials
A Maintenance-Wave Runbook for Firmware Upgrades on Enterprise…
A runbook that turns firmware upgrade work into a repeatable maintenance rhythm with inventory, ring/wave approach, validation metrics, and a rollback…
Tutorials
AAA on Network Devices with TACACS+: Command Authorization and Audit
A TACACS+ approach that reduces local admin sprawl on network devices and turns session traces into proof through roles, command authorization, and accounting.
Technology
Enterprise Edge Resolver Architecture with Anycast DNS
An approach for placing the in-house DNS resolver tier near the POP/branch using Anycast — cutting latency while improving operability.
Technology
IPv6 in Enterprise Networks: A Roadmap from Dual-Stack to IPv6-Only
A field-applicable plan for rolling out IPv6 not just as 'an address' but together with DNS, security, observability, and operational reflexes.
Tutorials
A Pre-Validation Pipeline for Network Changes with Batfish
A practical Batfish flow that validates routing/ACL changes before they reach production via 'snapshot + question set,' catching human error early.
Technology
DSCP and QoS on the WAN: End-to-End Prioritization
A guide to running QoS not as a magic wand but as an operational discipline managed with end-to-end measurement and a real trust boundary.
Tutorials
Network Drift with NetBox + Nornir: An Approval-Driven Remediation…
Detect configuration drift, approve fixes through Git, and apply them under control: source of truth → report → PR → rollout.
Technology
Reducing Outage Impact in Planned Maintenance with BGP Graceful…
Graceful restart logic, risks, verification steps, and a rollback standard for doing BGP maintenance without 'dropping routes'.
Technology
DDoS Response Runbook with BGP RTBH and FlowSpec
A controlled approach to reducing DDoS impact during operations using an RTBH/FlowSpec decision tree, verification steps, and a rollback plan.
Tutorials
Fast Failover with BFD on FRR: A Practical Guide
An approach to enabling BFD with FRR (BGP/OSPF) to generate fast signals when the link looks up but traffic isn't flowing (blackhole).
Tutorials
Linux Conntrack Capacity Planning and Alerting Runbook
A practical guide for generating signals before the nf_conntrack table fills up, applying safe sysctl tuning, and recovering in a controlled way during an…
Tutorials
Linux TCP Backlog and SYN Flood Resilience Runbook
A runbook to triage the connect timeout crisis when the SYN backlog/accept queue fills up, apply rapid mitigation, and design lasting resilience.
Technology
A Dedicated DNSSEC-Validating Resolver Layer in Enterprise Networks
An enterprise architecture approach that places DNSSEC validation in a dedicated resolver layer to raise trust in name resolution.
Technology
A Digital Twin Layer for Policy Drift in Enterprise Networks
A digital twin approach for seeing drift in firewall, routing, and segmentation rules without touching production.
Technology
RPKI-Based BGP Trust Chain in Enterprise Networks
An architectural approach to building an RPKI-based trust chain in enterprise networks to reduce BGP route leak and forged origin risks.
Tutorials
Multi-Point Service Health Monitoring with Blackbox Exporter
An installation guide that pushes a real reachability signal into Prometheus by running HTTP, TCP, and TLS checks from multiple network locations.
Tutorials
Designing an Enterprise Management Network Overlay with Headscale
A Headscale-based management network overlay guide for providing controlled access to scattered servers and management endpoints.
Tutorials
Continuous Vulnerability Validation on Internal Assets with Nuclei
A practical Nuclei approach for scanning internal network services with low noise and tying validated findings to your operations workflow.
Technology
A Backbone Capacity Planning Model for Enterprise Networks
An architectural model that manages backbone capacity ahead of growth by reading underlay and service traffic together.
Tutorials
An Egress Traffic Policy Layer with nftables
A guide describing how to set up an nftables-based egress policy layer to control which destinations servers can reach in the outside world.
Tutorials
Building a Link Latency Baseline with SmokePing
A SmokePing guide for making latency and jitter behaviour visible across branch, data center, and cloud connections.
Technology
Segment-Based Resolution in Enterprise Networks with DNS Firewall
A DNS architecture that separates the resolution flow per segment, reducing abuse risk, data exfiltration, and operational blind spots.
Technology
Shared-Service VPC Decision Matrix in Enterprise Cloud
An architectural framework that explains when consolidating DNS, egress, security and observability services into a single VPC is the right call.
Technology
Cybersecurity Fundamentals and Practical Tips
A guide that ties core security controls — identity, network segmentation, patch management and observability — into a checklist you can actually apply in…
Tutorials
Designing a Route Reflector Lab with Bird 2
Building a Bird 2-based route reflector laboratory to safely experiment with internal BGP topologies.
Tutorials
Publishing Services on Bare Metal Kubernetes with MetalLB
A clear design framework based on MetalLB for publishing services on bare metal Kubernetes clusters without a cloud load balancer.
Tutorials
Policy-Based Routing and Backup Link Design with Netplan
Set up a policy-based routing layout on Linux servers with Netplan that separates primary and secondary uplinks based on source network.
Tutorials
East-West Traffic Profiling with Suricata: A Practical Guide
A low-friction profiling approach with Suricata to make service-to-service traffic visible inside the data center.
Tutorials
Regional DNS Cache and Forwarder Separation with Unbound
A clean guide for separating resolution traffic across enterprise segments by configuring cache, forwarder, and access control with Unbound.
Tutorials
Just-in-Time Access to the Management Network with WireGuard
A practical WireGuard-based approach to building short-lived, auditable management access instead of permanent VPN accounts.
Technology
Jump-Host-Free Management Corridor in ERP Infrastructures
An enterprise access architecture that manages privileged access without depending on a single jump server.
Technology
BGP EVPN Segmentation Strategy in Enterprise Networks
An architectural framework for the BGP EVPN approach that makes segmentation more scalable in data center and campus networks.
Technology
Migration Strategy to an L3 Clos Fabric in Enterprise Networks
An architectural roadmap for moving from layered bottleneck designs to an L3 Clos fabric in growing data center networks.
Tutorials
Network Flow Observability with eBPF and SLO Correlation
An approach to monitoring network flows at the kernel level and correlating them with service latency and error budget signals.
Tutorials
BGP Failover Lab Guide with FRRouting
Steps for validating BGP failover behavior in a lab for servers or edge environments using dual uplinks.
Tutorials
Passive Health Checks for Internal Services with HAProxy
An HAProxy approach to catching internal service failures from real request flow without adding active probe traffic.
Tutorials
VRRP Failover for the Management Plane with Keepalived
A Keepalived-based VRRP failover approach for reducing single-VIP dependency in internal management services.
Tutorials
Protecting Management APIs with mTLS on Nginx
A simple and auditable mTLS setup on Nginx for protecting management APIs with client certificates.
Technology
Active-Passive Disaster Recovery for ERP Infrastructure
The fundamentals of building a realistic active-passive recovery model for ERP systems, covering data consistency, network routing, and operational roles.
Technology
DNS-Based Service Routing in Enterprise Networks
A framework for treating the DNS layer as a service routing and resilience control point, not just a name resolution service.
Tutorials
IPAM and Inventory Automation with NetBox
A NetBox approach for moving the network address plan and data center inventory out of ticket spreadsheets and into an automation-friendly model.
Technology
Integration DMZ Pattern in ERP Infrastructures
An approach for collecting partner and external service integrations in a secure intermediate layer without exposing ERP core systems directly.
Technology
Integration DMZ Design in ERP Infrastructures
An integration DMZ approach for connecting ERP systems to external services in a secure and manageable way.
Technology
Centralized Egress Design in Enterprise Networks
Principles for collecting enterprise outbound internet traffic into a visible, auditable, and scalable egress layer.
Technology
Out-of-Band Management Plane in Enterprise Networks
An out-of-band design approach that separates management access from production traffic on critical network and server infrastructures.
Tutorials
Gradually Tightening Kubernetes Network Policies with Cilium
A guide to moving Kubernetes network policy from observability into enforced control without breaking production.
Tutorials
mTLS-Based Service Identity Verification with Nginx
A practical Nginx-based approach to verifying service identity through mutual TLS for internal service traffic.
Technology
Resilience in Enterprise DNS and Service Discovery
Design principles for keeping the DNS and service-discovery layer in hybrid infrastructures from becoming a single point of failure.
Technology
East-West Traffic Visibility Without a Service Mesh
An approach for making east-west traffic visible across microservice and VM-based environments without standing up a service mesh.
Tutorials
Observing Linux Network Flows with eBPF
A guide for tracking flows, latency, and connection behavior on Linux servers with eBPF without drowning in packet capture.
Technology
Zero Trust Architecture on Enterprise Networks
How to build a Zero Trust approach across enterprise networks through identity, segmentation and observability layers.
Technology
Enterprise Defence with Zero Trust Network Segmentation
An observable and actionable Zero Trust segmentation approach that reduces lateral movement on enterprise networks.