linux networking Archives

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Mitigate DDoS with BGP Flowspec and ExaBGP on Linux: Automated Routing-Level Packet Filtering

October 19, 2026

Volumetric DDoS attacks can overwhelm Linux network stacks in seconds. Learn how to combine ExaBGP with BGP Flowspec to automatically push line-rate filtering rules directly into core routing silicon.

Networking

Route-Based IPsec VPN with strongSwan and VTI on Linux: Secure Cloud-to-On-Premises Connectivity

October 19, 2026

Build a route-based IPsec VPN on Linux with strongSwan and VTI. Learn how to configure XFRM marks, automate tunnel interfaces, avoid MTU black holes, and route hybrid cloud subnets without downtime.

Networking

Configuring a Captive Portal with CoovaChilli and FreeRADIUS on Linux for Secure Guest Wi-Fi

October 17, 2026

Build a secure guest Wi-Fi gateway on Linux using CoovaChilli and FreeRADIUS. This guide walks through Layer 2/3 traffic isolation, WISPr bandwidth limiting, and captive portal splash page integration.

Networking

Deep-Dive Network Performance Testing with iPerf3 on Linux: TCP, UDP, and Bottleneck Diagnostics

October 16, 2026

A 10 Gbps link often crawls at sub-gigabit speeds because of misconfigured socket buffers, packet drops, or MTU mismatches. Learn how to isolate real network bottlenecks on Linux using advanced iPerf3 TCP and UDP profiling.

Linux

Mastering Nftables on Linux: Modern Firewall Configuration to Replace Iptables

October 8, 2026

After six months running nftables across 12 production VPS instances, the migration from iptables turned out to be the best firewall decision I've made. This guide covers the real problems with iptables, how nftables solves them, and a practical migration process with a rollback safety net.

Networking

Deploying Layer 7 Real-Time Network Traffic Analysis with ntopng and DPI on Linux

October 4, 2026

Deploy ntopng and nDPI on Linux for real-time Layer 7 network visibility. This guide covers architecture design, Redis backend setup, promiscuous interface tuning, and practical troubleshooting workflows.

Networking

High Availability Virtual IP with Keepalived and VRRP on Linux: A 6-Month Production Review

October 3, 2026

A single gateway crash can bring down an entire stack. Here is a 6-month production review of implementing High Availability Virtual IP using Keepalived and VRRP on Linux, featuring real metrics, configurations, and post-mortem lessons.

Networking

Fixing Linux Network Lag: A Guide to TCP Retransmission

September 6, 2026

Is your Linux server feeling sluggish despite low CPU usage? Learn how to use ss, nstat, and TShark to diagnose TCP retransmissions and fix the network bottlenecks killing your performance.

Networking

Supercharging Linux Networking: A Practical Guide to eBPF TC

September 1, 2026

Ditch the overhead of iptables. This guide shows you how to use eBPF TC to build high-performance, programmable network filters and QoS directly in the Linux kernel.

Networking

DNS Tunneling with iodine on Linux: Bypass Firewalls and Access Networks via DNS Protocol

August 29, 2026

Learn how to set up DNS tunneling with iodine on Linux to bypass firewalls in restrictive network environments. This guide covers server setup, client connection, traffic routing, NAT configuration, and practical troubleshooting tips for authorized use cases.