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Understanding OpenStack Networking: Geneve, VXLAN, and Hardware Offloading Explained

Demystify OpenStack networking. This comprehensive guide breaks down the critical differences between OVS and OVN, explains why your overlay defaults matter, and outlines the exact hardware offload strategy needed to hit 100 Gbps efficiently.

Architecting High-Throughput Databases: Galera’s Synchronous Certification vs. PostgreSQL’s Decoupled MVCC and the Vacuum Trap

When engineering infrastructure for massive scale, the underlying database topology becomes the ultimate chokepoint. Traditional deployment paradigms often mask a harsh reality of connection bloat, network-bound deadlocks, and strict physical throughput limits. To design data planes that do not violently collapse under heavy concurrent workloads, architects must make a definitive choice between…

The CNF Illusion: Navigating the Realities of Cloud-Native Networking

If you keep an eye on the infrastructure space, you’ve almost certainly seen the headlines. The prevailing narrative—echoed in countless medium articles and vendor pitches—is that Cloud-Native Network Functions (CNFs) are the undisputed future, systematically replacing traditional network appliances and legacy Virtual Machines in 5G and enterprise networks. The pitch is undeniable: package your…

Automation Via UEFI

In large-scale datacenter environments, traditional BIOS-based automation quickly becomes a bottleneck. This post explores how I automated server provisioning and RAID configuration directly through UEFI, without using a live OS. From building a bootable ISO with xorriso to embedding BOOTX64.EFI from EDK2, we’ll walk through each step — creating startup scripts, managing RAID controllers, and…

Brief Introduction to Zimbra Internal Architecture

In some cases, you might want to recover your data from Zimbra, or you may be curious about how Zimbra manages users and emails behind the scenes. I dug into Zimbra’s nuts and bolts because we lost Zimbra’s local LDAP, which took more than 3 days to fix, so I wanted to share what I Read More

SSH Access Without OS Shell in Gitlab

Exposing SSH of your gitlab on the internet could be dangerous as attackers can get shell access into your server. So here we show you a way to enable SSH for Git without opening access to shell of the hosting OS. Step 1: Run another SSH instance just for gitlab Copy sshd config file and Read More

Provisioning DNS Server Using PowerDNS

When you want to setup a DNS server on *nix platform, the first option that may cross your mind is bind9. But there are other options such as PowerDNS. In this post I’m going to show you how to setup a DNS server in single node mode. This DNS server is going to be authoritative Read More

Using Putty to Automate Cisco Devices

Sometimes you want to automate some cumbersome tasks in your Cisco devices, namely I am dealing with an old 3750 core router with OS version 12.x and I don’t want to login to it manually every time I want to change a config or shutdown an interface. Hence I thought I can make use of Read More

Using Maven with Socks Proxy

For bypassing using socks proxy use following command : mvn install -DproxySet=true -Dsocks.proxyHost=YOU_SOCKS_PROXY_ADDRESS -Dsocks.proxyPort=SOCKS_PROXY_PORT This command works in Linux and Windows Happy coding.

How to Create JWT Token Using LDAP and Spring Boot Part 1

If you are working in an enterprise infrastructures, chances are that you are using a centralized authentication system, most likely Active Directory or openLDAP. In this blog I’ll explore how to create a REST API using spring boot to authenticate against openLDAP and create a JWT token in return. Before getting our hand dirty, we Read More