Thursday, January 22, 2015

The Art of Decision Making - Sunk Costs

One of the life changing concepts I have recently learned during my MBA studies is to when effectively walk away from a business. Let's face it, we have more or less been all living in a society which dictated the myth that as long as we have previously invested substantial energy, time and money into something, we should continue doing it, even if the future benefit might get negative or we just hope to bring in some profit.

After studying about the concepts of relevant costs I do not agree with this traditional reasoning - past costs, known as sunk costs, should be never accounted in future decision making. You should just look at the present...the t = 0, when considering costs... Look at it this way - wondering about the future? Then consider only the FUTURE costs and the FUTURE benefits. The future benefit should always be more than the future cost if you decide to give green signal to a project.

For most people, including business men, they find it difficult to detach themselves from something which costed them lots of money and energy to get that far and they aren't seeing the profit yet. This is wrong.

Now quick question for my blog readers to ponder about: How many times did your manager, CEO or CFO, base his financial decisions on irrelevant sunk costs? And what can you tell about the outcome of such decision?

Saturday, December 13, 2014

Change LUKS disk encryption key

This morning I wanted to "cleanup" the work laptop to pass it over to a new colleague in the team. Then I remembered that I have used my LUKS password in other applications. Unwilling to share this password I decided to take the plunge and change it! These are the steps needed:

1. Determine the device with LUKS encryption:
╭─root@darktech  ~
╰─$ dmsetup ls                                                                                                                                                                                fedora-win8     (253:9)
fedora-backtrack        (253:6)
fedora-swap     (253:1)
fedora-root     (253:2)
luks-eca67822-2122-44ab-9dc7-2f13c8e94d6f       (253:0)
fedora-data     (253:7)
fedora-winxp    (253:4)
fedora-backup   (253:8)
fedora-f18      (253:5)
fedora-home     (253:3)
╭─root@darktech  ~
╰─$ dmsetup info luks-eca67822-2122-44ab-9dc7-2f13c8e94d6f
Name:              luks-eca67822-2122-44ab-9dc7-2f13c8e94d6f
State:             ACTIVE
Read Ahead:        256
Tables present:    LIVE
Open count:        9
Event number:      0
Major, minor:      253, 0
Number of targets: 1
UUID: CRYPT-LUKS1-eca67822212244ab9dc72f13c8e94d6f-luks-eca67822-2122-44ab-9dc7-2f13c8e94d6f

╭─root@darktech  ~
╰─$ pvdisplay
  --- Physical volume ---
  PV Name               /dev/mapper/luks-eca67822-2122-44ab-9dc7-2f13c8e94d6f
  VG Name               fedora
  PV Size               465.08 GiB / not usable 0
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              119059
  Free PE               0
  Allocated PE          119059
  PV UUID               yXSVeR-pwc4-nkJt-EXWq-CiLA-2XPs-qwdQVu

2. Create a new LUKS password:
╭─root@darktech  ~
╰─$ cryptsetup luksAddKey /dev/sda3                                                                                                                                                          
Enter any existing passphrase:
Enter new passphrase for key slot:
Verify passphrase:
╭─root@darktech  ~

3. Remove the first slot:
╭─root@darktech  ~
╰─$ cryptsetup luksKillSlot /dev/sda3 0                                                                                                                                                      
Enter any remaining passphrase:

The first slot is "Slot 0", second is 1, etc. Make sure you don't remove the wrong slot or you will lose your data permanently!

Friday, November 21, 2014

2015 Malta Eurovision Song Context - a review

Times of Malta have posted a lighthearted "Idiots' guide to 2015 Malta Eurovision Song Context" article this morning.

Of particular amusement the tongue-in-cheek reference to Lawrence Grey's "never giving up" experience with this song context, and Ludwig's sleek image:

Lawrence Grey - The One That You Love

“I’m never gonna be the one that you love. Is there a way that I can win your heart?”
I love the way our Lawrence never gives up and now he’s even spelling it all out to the audience, in a quite catchy, croony song.
The question is, though, Will the audience get the message?

Trilogy - Chasing A Dream

The trio is made up of Eleanor Spiteri, Roger Tirazona and Ludwig Galea.
Roger and Eleanor and diction don’t go hand in hand: Traaying Harrrd.
I love Ludwig and his sleek, blow-dried, Japanese straightened mane, and the way his vein in the neck pops when he reaches high notes and the way he throws himself, back, then to one side, then to another, then back again, when he’s reaching all the other notes.

Thursday, November 20, 2014

Improving your database backup policy

In this brief article I will reflect on a strategy which I normally adopt in an enterprise which requires a solid database backup policy in which frequent regular backups of their data-set is needed.

First and foremost get familiar with a filesystem snapshot technology; whether an enterprise tool such as VMware's Veeam, or something like LVM. Secondly, get familiar with a replication technology of your database system, for example in MySQL we have master-master or master-slave.

The strategy can be explained in these simple terms is:
  1. Stop replication
  2. Stop database service on slave/secondary node
  3. Take a snapshot of the slave/secondary node
  4. Start replication
  5. Repeat steps 1 - 4 every hour
  6. Repeat steps 1 - 4 every day at midnight
  7. Repeat steps 1 - 4 every first day of the month at midnight
  8. Every Sunday at midnight, purge all hourly backups of the previous week
  9. Every first day of the month at midnight, purge all daily backups of the previous month excluding the first day
Now you have a nice catalog of backups which allow you to also do point-in-time recovery by applying binary logs in between backups. Adjust backup retention as necessary.

Wednesday, November 19, 2014

Did my first 12km run ever!

Or to be precise, my first 12.56km. Before that, I had only ran about 9 more times for the first time in my life, with the first run resulting in me getting knackered after the first 5 minutes!

I started running as soon as I started my MBA programme to help me keep focused and sharp between work and studying activities. Thereafter it became more like "the thing to do" after work.

Goes without saying that I do have a goal: that to be able to do the half marathon which is next February. I am half way through it, consistently improving and pushing myself within reasonable limits. Some stats:

Wednesday, November 05, 2014

Personal Development assessment

This morning I submitted the Personal Development Stage 1 assessment having worked on it for the last 30 hours. With a mere pen and paper I managed to get intimate with my thoughts - I have used the Henley Star model to define some objectives and how the Henley MBA can reach them. When defining the objectives, I have use the SMART goal approach.

Writing a timeline of my personal development since I was born till now made me reflect how my family and community have shaped the person I am today. When I mapped these life events to the psychosocial 8-stage model (Erikson, 1950), I found out that stage 5 was crucial and some key learning events were brought up thanks to decisions taken during this stage.

I will use this blog as my personal journal to do my best and reflect and succeed in my life.

Sunday, October 26, 2014

First workshop at Henley

Our honeymoon period at the Henley business school is approaching to its end. During this first workshop for the module Personal Development we had the opportunity to reflect on ourselves and to identify what has brought us here, to pursue the MBA programme.

I personally found these last couple of days more interesting than I was expecting. Some of my favorite highlights:

1. The tutors are fun, very communicative and we managed to crunch a wealth of information in just a few days!

2. My group intake, the MT09, is a mix of interesting people from Malta, Lebanon, Italy, Libya and Spain. Moreover I was surprised to meet a good number of fellows from different backgrounds and experience - I was personally expecting a bunch of boring accountants ;)

3. The team learning exercises made me reflect on who I really believe I am and helped me shape a bit better my future goals and aspirations. Making dialogues with other peers also made me realize that I share the same issues and concerns with other people and that I share the same goals with others.

4. The course content looks tough, but with that in mind I am pretty sure we can do it - and I am being realistic here. I believe that with a solid time schedule and 12 hours a week to spare for the MBA, we should have a good chance of keeping up a  good pace. And this is like a marathon after all.