Sunday, February 12, 2017

Quick Docker environment cleanup

Just a quick reference on my docker usage.

When working / playing with docker a lot, you quite often end up with a ton of containers and volumes laying around after they are needed...

Here are a couple tips I use to keep my environment clean.

On Windows 10
If you are using GitBash create a .bashrc and include the commands below:

alias docker-rm='docker rm $(docker ps -q -f status=exited)'
alias docker-rmi='docker rmi $(docker images -q -f dangling=true)'
alias docker-rmv='docker volume rm $(docker volume ls -q -f dangling=true)'

For MacOS X 
Add the following to your .bash_profile:

docker rm $(docker ps -q -f status=exited)
docker volume rm $(docker volume ls -q -f dangling=true)
docker rmi $(docker images -q -f dangling=true)
docker-update-all() {
docker images | awk '(NR>1) && ($2!~/none/) {print $1":"$2}'| xargs -L1 docker pull

Then simply run docker-rm, docker-rmi and docker-rmv to remove all the dangly bits :)

docker-update-all, is a handy way to get the latest images from docker hub.

Sunday, December 18, 2016

AWS Solutions Architect - Professional Certification

Let me start by saying, for this certification I studied and prepared more than any certification I have done before and I have done a number of certifications throughout my career; Microsoft, Sun, IBM, Oracle and now AWS. It does feel like there is a mountain of content to get through, and then ensuring you know it at the correct level of detail for the exam.

I booked the AWS Solutions Architect Professional exam 5 weeks after the associate level one and set a couple hours a day aside to study... During the last 2 weeks however, those couple hours became all my available hours every day, it was all I focused on, including 8+ hours a day on the weekends.

Main 4 resources I used:
  • YouTube
    • The re:Invent sessions videos are an essential resource
    • My major topics playlist: 

    • Watch these twice:

  • Linux Academy 
    • These guys really impressed me, the content in the pro level certificate was excellent, I found it had more depth than A Cloud Guru, well worth the $29 per month subscription.
  • Cloud Guru
    • Decent structured content that covers the highlights of all the topics defined in the exam blueprint.
    • The discussion forum is an excellent source of tips and discussions on the practice exam questions.
  • The official practice exam
    • This was a good eye opener, into how hard some of the questions can be. I do feel that some of the questions are badly articulated which makes them almost impossible to answer, however working through every question and researching the answers was invaluable. There were also a couple of those questions on the real exam... word for word.

Other Resources (Summary  / Study Notes):

Final thoughts:

All the guides and sites recommend reading a ton of white papers, but to be honest, I read only 4 or 5 of them..and I felt that the time spent was a waste. It seems all the content was in all the youtube vids and online courses already.

I did see a lot of people mention that they were pressed for time during the exam, but I found that I finished the 77 questions with a good hour to spare. To mention though: I did not go back and review any of my answers. I have always found in the past, that I rarely change my initial answer during the review phase, and I was reasonably confident that I had done enough.

End Result:

Overall Score: 83%

Topic Level Scoring:
1.0 High Availability and Business Continuity: 90%
2.0 Costing: 100%
3.0 Deployment Management: 85%
4.0 Network Design: 57%
5.0 Data Storage: 81%
6.0 Security: 78%
7.0 Scalability & Elasticity: 90%
8.0 Cloud Migration & Hybrid Architecture: 85%

Saturday, November 12, 2016

AWS Solutions Architect - Associate Certification

I have been messing around with AWS on little side projects and experiments for about the last year. I did find it quite a daunting experience as there is just so much to learn, do, try, break, struggle, deploy, re-learn and then eventually cheer when everything works.
So I decided to focus a little more and spend the time actually learning how to hopefully do all this properly. I have always found a good way to force myself into the theory and step back from diving directly into implementing solutions is certifications.

I booked the AWS Solutions Architect Associate exam for 4 weeks into the future and set a couple hours a day aside to study.

Main 2 resources I used:

  • A Cloud Guru
    • I did watched and worked through both the Associate Developer and Associate Architect courses. There is quite a bit of overlap, but still that just meant that I had covered some of the really important bits more than once.
    • I really enjoyed Ryan's courses, I did mostly watch on 1.3x speed as it does sometimes feel a little slow and I had set myself a 4 week dead line.
    • I would recommend them to anyone starting who's looking to learn about AWS, for practical real life use or certification.
    • The discussion section / forum is a great source of tips for the exams as well.
  • Cloud Academy
    • I only signed up for their 7 day free trial, so did not work through all of their labs. However they have a ton of quiz questions and explanations which is a great way to study / practice specifically for the certification.
    • Their summary video was also good and covered some content not covered in depth on a cloud guru.
    • They also had some quick easy reading blog posts highlighting important practical information when starting with AWS... listed in Other resources below.
Other Resources:

The main aws faqs to look at:

In the end I felt I had personally learnt a lot, not only on the exam topics but in general practical application as well. Main areas were especially with regards to VPCs, Networking and Security. It was well worth the intense 4 week study session.

End Result:

Overall Score: 90%
Topic Level Scoring:
1.0 Designing highly available, cost efficient, fault tolerant, scalable systems : 90%
2.0 Implementation/Deployment: 83%
3.0 Security: 90%
4.0 Troubleshooting: 100%

Next up.. AWS Solutions Architect - Professional

Saturday, October 8, 2016

TOGAF 9.1 Notes

I was considering doing the TOGAF 9.1 certification. I have gone over all the content, to at least have a decent idea, what TOGAF is and what it is trying to achieve.
However based on my current position, interests and trends I decided to rather focus my attention elsewhere for the moment.

So just to note down all the resources I found, used and other relevant resources links incase I do have the time or the need to come back to it.

Training course UDEMY (Scott Duffy):
I would avoid the Exam Strategy one ( as I found it a little bit of a waste, and he covers a lot of the content in the other 2 courses anyways.

Books / PDFs:
The Actual TOGAF specification (PDF)
TOGAF 9 Foundation Exam Study Guide
TOGAF 9.1 Quick Start Guide for Enterprise Architects (Not sure where I got a PDF from)
TOGAF Cheat Sheet from Scott Duffy's Udemy course.

Other Useful Resources:

Sunday, September 11, 2016

Oracle Workspace Manager - Basic POC with Spring Boot and Flyleaf

Working with a process to update configuration and master data within an enterprise is always a challenging task. While investigating possible solutions on how to have someone change data via a UI, then have those changes tested, signed off and approved before taking it to production. I stumbled on to Oracle Workspace Manager.
According to their developer docs, it seemed fit this use case exactly:

Manage a collection of updates and insertions as a unit before incorporating them into production data
Workspace Manager lets you review changes and roll back undesirable ones before making the changes public. Until you make the changes public, they are invisible to other users of the database, who will access only the regular production data. You can organize the changes in a simple set of workspaces or in a complex workspace hierarchy. A typical example might be a life sciences application in which Workspace Manager supports the discovery and quality assurance (QA) processes by managing a collection of updates before they are merged with the production data.

You could think of Oracle Workspace Manager as light "git"-like db versioning. 
Simply put:

  1. You create a workspace (branch)... 
  2. You make your changes there.. other people can connect to your workspace .. also make changes... or alternatively create their own branch from yours.
  3. You can refresh (fetch / merge) your workspace and resolve any conflicts that arise.
  4. Once everything is sorted and all is well with your changes you merge it back into the "LIVE" (origin: develop / master) workspace.

I used an existing Docker image of a oracle standard edition version. Oracle Workspace manager is not available on XE unfortunately. This is a rather large image, and it does take a couple minutes to initialise. The image is available on here on Docker Hub.

Connect database with following setting:
hostname: localhost
port: 1521
sid: xe
service name:
username: system
password: oracle

To connect using sqlplus:
sqlplus system/oracle@//localhost:1521/
To connect on mac os - install instantclient and run from there:

./instantclient_12_1/sqlplus system/oracle@local

To setup the initial DB I tried out Flyway. All quite simple and easy to implement. 
Under resources/db/migration there are a number of sql files that do the initial database setup.

  1. create the tables: CODE and CODE_TYPE, 
  2. insert initial data 
  3. enable versioning on those tables.

When you enable versioning the following happens, the table is renamed and a view is created allowing the "recording" of changes that occur.

Reference: (oracle presentation available here)

So after the initial setup you will seen a number of tables and views:

To try this out...

  1. Get the Oracle Docker image
  2. Once the DB is started... run the boot DataApplication.
  3. Use Postman on the REST resources below

To check the current workspace:
GET: http://localhost:9119/poc/workspace
To select all the information from the code table for the current workspace:
GET: http://localhost:9119/poc/workspace/data/code
Create code in the current workspace:
POST: http://localhost:9119/poc/workspace/data/code
"descr": "some code",
"type": 1
To change workspace (LIVE is default and available):
PUT: http://localhost:9119/poc/workspace/{workspaceName}
To create a workspace:
POST: http://localhost:9119/poc/workspace/{workspaceName}
To remove a workspace:
DELETE: http://localhost:9119/poc/workspace/{workspaceName}
To merge a workspace:
PUT: http://localhost:9119/poc/workspace/merge/{workspaceName}

These REST resources just wrap some of the functions from the DBMS_WM Package
This is maybe just the tip of a iceberg, as there is a ton of functionality available from this package.

All the code is available here.

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