Saturday, June 19, 2021

Installing Nutanix Community Edition above Vmware ESXi without SSD

No detailed write up. Just the points.
I wanted to test Nutanix Community edition. I have Dell poweredge M630 blade server with only two HDDs ( 512 GB) in RAID-1 configuration. Nutanix CE requires minimum 2 SSDs. Inorder to emulate this, I installed VMWare ESXi hypervisor. The steps for this is easily available. Now create a VM in this VMWare ESXi hypervisor, which will be our Nutanix AHV host. So it is a hypervisor over hypervisor.

Saturday, July 04, 2020

How to bypass a website ban by DNS over HTTPS?

Recently I found that my default search engine DuckDuckGo (duckduckgo.com) was not opening in any web browser, while all other websites are working fine. In a basic troubleshooting, I found that my ISP ( ACT Fibrenet in Bengaluru, India) is blocking my DNS query to duckduckgo.com. ( See my blog on Domain name service DNS ).

DNS-over-HTTPS (DoH)

What is Domain name service (DNS) ?


When we type a URL address in any internet browser like google chrome or Internet explorer, the browser translates that name to something it understands, a number, called IP Address. In Internet, all the connected devices have an unique IP address. Eg: Google website ( google.com or google.in ) has an unique IP Address, Yahoo has its own address. It is difficult to remember all these addresses, that is when DNS helps us. A server running this DNS service maintains a table to translate the Name to IP Address to make things easy for humans

Monday, January 13, 2020

Extending Multiple VLANs over trunk interface to Windows Server

Physical setup:

A Microsoft windows server with two NICs connected to a Network switch. There is a requirement to extend multiple VLANs to the server.

Steps:

Configure the network switch interfaces connected to the server as trunk ports. Trunk ports allow multiple VLANs to pass-through. Technically, All the packets passing through trunk ports must have an VlanID in the ethernet packet. the receiving switch decides where to forward the packet based on the VlanID tag. If any packet arrives without VlanID, it is considered as packet belonging to the VLAN marked as "Native VLAN". In cisco switches, "Vlan 1" is the default "Native VLAN".
Cisco Switch commands:

Friday, March 13, 2015

IPv6 Internet access from IPv4 (BSNL) DSL Connection

As of now AFAIK BSNL, the largest ISP in India, is not providing IPv6 Internet to DSL home users. So here is a cool way to connect to IPv6 Internet using a IPv4 DSL connection.

Scenario:
I have a BSNL DSL Broadband connection with dynamic IPv4 address with NAT.
Here I will demonstrate a way to access IPv6 Internet using a IPv6-over-IPv4 tunnel from tunnel broker Hurrican Electric. I am running Ubuntu Linux 14.04.

TL DR:

Signup with any IPv6 tunnel brokers in internet like Hurrican Electric or SixxS. Create a regular IPv6 tunnel. Add v4tunnel interface configuration in our computer.

Friday, October 17, 2014

Enabling developer options in Android 4.1+

Developer options like USB debugging are by default disabled in Android 4.1+ ( Android 4.2, Android 4.4.4) and the menu to enable is hidden!.

To Enable Developer Options:

  1. Go to "Settings"