Airflow mode of Cisco Nexus 93180yc FX3

I need to rack and stack Cisco Nexus 93180yc FX3 in my datacenter, therefore, I need to know what airflow mode to choose.

The Nexus 9K datacenter switches support two airflow modes

1. Portside intake - sucks cold air into network ports and blows warm air out of the power supply's  into hot aisle 
2. Portside exhaust - sucks cold air into power supply's and blows warm air out of the ports into hot aisle

The network ports should be located on the same side of the rack as the server’s rear panel, therefore, I need portside exhaust airflow mode.

Hope this helps other IT guys in the field. 

IPv4 Addresses Cheat Sheet

Bellow is my cheat sheet about IPv4 addresses and sub-netting.

 

 

The cheat sheet is primarily for myself :-), but somebody else can find it helpful and use it.

Description: The math binary representation of IP octets (bytes) and relation to Net Subnetting.

Keywords: Class Addressing, Classless Addressing, Tips & Tricks

 

VMware Fusion: Mount hgfs into Ubuntu Linux

This is a very short blog post. Here is the procedure howto manually mount macOS shared folders into Ubuntu Linux running as VM in VMware Fusion ...

sudo vmhgfs-fuse .host:/ /mnt/hgfs -o allow_other

Why does a shut down Dell server consume 50W?

Question: Why does a shut down Dell server consume 50W?

 

Short Answer: Because some hardware components still consume power when the server is not disconnected from power. 

Longer Story with details 

I have Dell PowerEdge R620 with iDRAC7 in my home lab and here is the home power consumption in two scenarios

1. shutdown server still connected to power (531 Watts)
2. server fully disconnected from the power (475 Watts)

Scenario 1: shutdown server still connected to power

 

Scenario 2: server fully disconnected from the power

The difference between above two scenarios is ~ 50W. Why? 

Let's dive deeper. 

FortiGate Configuration Backup via REST API

One of my customers would like to backup FortiGate configuration as part of DRBC (Disaster Recovery and Business Continuity) Solution.

FortiGate supports REST API so it is great solution to periodically get configuration, store it into some file directory and leverage Veeam Backup and Replication solution to backup FortiGate configurations in with company standard protection process. 

In this blog post I document all customer's specific design factors and also the solution prototype how to fulfill these factors and backup FortiGate configuration into file directory.

I personally prefer *nix way over Windows, therefore, I will leverage Linux Docker and PowerShell to get information from FortiGate security appliance and put it into file directory. Docker solution could be leveraged on Windows operating systems as well.

If you are interested in details, read on.

David Pasek’s version of Greg Ferro’s 11 rules of design

Design documentation is not literature; it is a technical tool. The goal is clarity, precision, and usability. Here are 11 rules to guide you when writing a design document.

Greg Ferro's Eleven Rules of Design Documentation

Here is Greg Ferro’s approach to designing network design documentation. The “world” of networks is too big and varied to have only one document to cover more than one or two projects, but here are some rules to write a detailed Design document.