Why am I writing this?

Lately, I am doing more and more Azure stuff and find that terms are thrown around that I have trouble understanding. I, of course, went on Youtube and looked up a video on Azure. One by John Saville on Managed Identities popped up.

As a student in computer science, I decided I should listen, learn, take notes, and eventually apply.

To make sure I really understand it, I will write it here so that I am an idiot.

You finish your day, get home, put your bag down and hug yor cats (or kids ;) ). You hear a noise from your phone: A notification… From work. It’s almost 7PM, you had a long day and you simply want to wind down. You debate ignoring the message, but your work ethic kicks in and makes you look. It’s in the incident channel, never a good sign. Production is down. The web application is not responding and is showing a white screen. The feeling of dread starts in your stomach as you hurridely get your laptop out and venture forth your aid.

What is an IP Address?

Let’s start with the basics.

IP Address Classes

Class A
    Public range of 10.0.0.0 to 127.0.0.0
    Subnet mask: 255.0.0.0
    Number of Networks: 126
    Number of hosts per network 16,777,214
Class B
    Public range of 128.0.0.0 to 191.255.0.0
    Subnet mask: 255.255.0.0
    Number of Networks: 16,382
    Number of hosts per network 65,534
Class C
    Public range of 192.0.0.0 to 223.255.255.0
    Subnet mask: 255.255.255.0
    Number of Networks: 2,097,150
    Number of hosts per network 254
Class D
    Public range of 224.0.0.0 to 239.255.255.255
    Number of Networks: n/a
    Number of hosts per network multicasting
Class E
    Range: 240.0.0.0 to 255.255.255.255
    First octet value range from 240 to 255
    Number of Networks: N/A
    Number of Hosts per Network: Research/Reserved/Experimental

So, what does all this mean?