Site Sponsors:
Public DNS to AWS VPC on EC2 
There has simply GOT to be a good anagram in the title for this post somewhere ... ;-)

New to WHO?


Sadly, the folks at Amazon & elsewhere do not know that Clouds were being enshrined on blackboards & plastic (flowchart) stencils well before the Internet was a keyword.



Indeed, if it was not for the fact that things like REST caused folks to spend billions of dollars fixing things that were never broken in the first place - if so many new-wheel / old-wheel fire-drill were not so expensive - such over-hyped fire-drills would be comical. (*)

Reality


For financial reasons alone, many feel the the unfortunate tendency both new folks to the industry & the media have to shout "eureka" when re-discovering the wheel is truly unnerving.



And so it goes with AWS and EC2 - Rather than working with a box of well ordered tools, one often feels that they are instead working with a young ESL kid who is trying to describe what is in a newly-opened box of freshly-caught frogs. While the overall experience is extremely flexible and ready to take on any computing challenge, anyone who knows what they are doing is in for a rather amusing - and probably a needlessly time consuming - journey.

What pat of the term DNS ... ?


For example: After mucking about with Amazon Web Service (AWS) for any length of time, you will undoubtedly want to link a PUBLIC URL to your Virtual Private Cloud (VPC.)

VPC Misnomer


First and foremost note that the official name for "VPC" is surely a misnomer!

Why? Because Multicomputer Clouds do not have single-entry command prompts.

In short, one must use SSH (etc) to get a command prompt on your VPC so as to manage Operating System (OS) commands - just as one would do on any PC OS.

Rather than being any type of as-named "private cloud" however, this VPC is - in reality - a Virtual Personal Computer (or "PC")! (VPC == Virtual Linux / Windows P.C)

Wristwatch?


Moreover, the free Amazon VPC one most often encounters is certainly in no way even a "Personal Server:" Most cell phones have more memory & data storage these days. (Indeed, how could any modern P.C. of any description have so little RAM + storage? My Raspberry Pi and Beagle Bone Black microcomputers have as much!)

So the pseudo-technical folks might call the AWS-PC a cloud-prince... but after we kiss it, it still smells like a somewhat underfed frog to the rest of us? (Not to mention the warts-for-today I'm 'talkin 'bout ;)

What type of "warts" you might ask? -Well, unlike a multi-host "Cloud" of any description - yet just like any PC - your VPC will have an IP address. Unlike a PC however, at the time of this writing the default IP Address and public Domain Name Service (DNS) endpoints will change every-time the VPC is re-started (Instance) on the EC2.

Moving Target?


The problem with the new-IP-on-reboot strategy is that the entire point to having a Domain-Name Service is to associate a static "name" with a far more changeable IP Address. Hence - and unlike what most 'geeks of any tenure are used to - using that default Amazon-generated DNS entry becomes just as pointless as hard-coding that ever-changing IP address into your application(s)!

So if one might be tempted to (1) assume that your VPC will never be restarted & simply (2) create another DNS A Record to (3) point to your default DNS VPC instance-name, note that if you ever (4) re-boot your VPC off of the EC2 that the A Record will simply (5) become a pointer to a tombstone.

What's a geek to do?

Elastic IP Address


Like most things AWS, there is a way around everything.


In this case, after a few hours I discovered that the terrarium includes the ability to create a STATIC IP address (Colloquially speaking, static is not very "elastic"? -But with a little thought & tolerance, the concept works for me. -Such is the pattern with all things AWS ;)

Once created, one can THEN associate that "elastic" address with a running Instance of your VPC on the EC2, as well as create an A Record that will also refer to that far more immutable name, as well.

So sure, dynamically instancing a bevy of VPC clones onto the EC2 so as to allow them to "expand and contract" on-demand is a very cool idea. -Just like a "dial group", the idea of having a single phone number round-robin ringing any given set of telephone hand sets was cool even back in the 1950's.

Yet every rational regionalist knows that a frog-in-a-cloud - by any other name - is still a frog?


Sharing is caring!

-Rn



(*)
Yes, in 1970 mainframes were trying to do "in-cloud" computing, as well ;)

Rather than having any historical context, new kids seem to want to re-discover everything from the concept of "web service" (what do all those RFC's describe, anyway? HTTP? HTTPS? HTML Forms?) to "the Internet of things" (was a UAV, PDA, set-top box, poll-top electric transformer, IP:X10 network, or oil rig not a "Thing"?

Do these new, visionary, "things" not have computers in them, as well?? IP?


--So overlooking the jibes in the postscript herein we must simply ask ourselves: Did we miss something here... or did someone else?

[ view entry ] ( 710 views )   |  permalink  |  related link
Let's Get Professional! 
Enough is enough already: Just because one is a new software developer does not mean that one should not know how to design & document what one needs to do!

Mission: POSSIBLE!


In as much as I often work with folks who could use a 'tad more insight into what professional software developers need-to-know to design & capture requirements, I wanted to do my best to help.

Professional Java 8100: Design, Frameworks & Threads


YouTube Lectures


Submitted for your approval please find the first public release of a 1-hour video presentation. -Known as "Professional Java," my goal is to allow you to experience a first-class training exercise. A quick view of a one-two lecture / lab punch. A set of three lessons designed to allow those who already know how to use Java discover what software developers most often need-to-know on-the-job.

Freely available on YouTube, my hope is that this 1-hour training + 1 hour lab seminar will help you take your career to the next level.

Introduction: Why the Training
Part One: Console Threading
Part Two: Designing Messages
Part Three: GUI & Frameworks

Lab Exercise Booklet


Like any professional training opportunity, you can also get the lab exercises & source code.

Part Labs: Labs & Code



See the related link (below) for more information.


Sharing is caring!

-Rn

p.s: If you want learn about Java, then feel free to join the group.

[ view entry ] ( 794 views )   |  permalink  |  related link
Dropping that firewall: CentOS & RedHat! 
When you are working on your own cluster - behind your own firewall - then having ANY type of port-security on an on-demand server is just plain 'ol annoying.

Here is how to allow access to ALL of those ports on your R&D server. -Wherever iptables is 'empestered:

su
service iptables save
service iptables stop
chkconfig iptables off
service iptables restart

Now Tomcat, 8080, 80, and (etc, etc,) will respond as most software developers are used to.


Sharing is caring,

-Rn


p.s: Ubuntu Tomcat users can do this.

[ view entry ] ( 824 views )   |  permalink  |  related link

<<First <Back | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | Next> Last>>