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October 2011

The art of getting security right-an observation

A number of high-profile hacks recently (and not so recent) has caught my attention. Well I thought, not such a big problem-I don’t have a PS3 and hence don’t have an account that can be hacked. I was still intrigued that the hackers managed to get hold of the passwords. I may be wrong here, as I haven’t followed the developments not close enough (as I wasn’t affected), but the question I asked myself: how can they be obtained? Surely Sony must have used some sort of encryption for passwords. It’s so far-fetched that anybody stores passwords in clear text somewhere!

Oh well then, Sony has been targeted a number of times and time and time again the security was breached. They only consolation is that the intruders have made it very public when they were successful, otherwise we’d have never learned about the problems Sony has with security.

Now other sites were hacked as well, and somehow I felt the impacts coming closer, such as kernel.org and others.

Friday Philosophy – The start of Computing

This week I finally made a visit to Bletchley Park in the middle of England. Sue and I have been meaning to go there for several years, it is the site of the British code-breaking efforts during the second world war and, despite difficulties getting any funding, there has been a growing museum there for a number of years. {Hopefully, a grant from the Heritage Lottery Fund, granted only this month, will secure it’s future}.

Why is Bletchley Park so significant? Well, for us IT-types it is significant because Alan Turing did a lot of work there and it was the home of Colossus, one of the very first electrical, programmable computers. More generally of interrest, their efforts and success in cracking enemy ciphers during WW2 were incredibly important and beneficial to the UK and the rest of the allies.

In this post, I am not going to touch on Colossus or Alan Turing, but rather a machine called the “Bombe”. The Bombe was used to help discover the daily settings of the German Enigma machines, used for decrypting nearly all German and Italian radio messages. All the Bombes were destroyed after the war (at least, all the UK ones were) to help keep secret the work done to crack the cyphers – but at Bletchley Park the volunteers have recreated one. Just like the working model of Babbage’s Difference Engine, it looks more like a work of art than a machine. Here is a slightly rough video I took of it in action:

My slightly rough video of the bombe

{OK, if you want a better video try a clearer video by someone else.}

I had a chat with the gentleman you see in both videos about the machine and he explained something that the tour we had just been on did not make clear – the Bombe is a parallel processing unit. Enigma machines have three wheels. There are banks of three coloured disks in the bombe (see the picture below). eg, in the middle bank the top row of disks are black, middle are yellow and bottom are red. Each vertical set of three disks, black-yellow-red, is the equivalent of a single “enigma machine”. Each trio of disks is set to different starting positions, based on educated guesses as to what the likely start positions for a given message might be. The colour of the disk matches, I think, one of the known sets of wheels the enigma machines could be set up with. The machine is then set to run the encrypted message through up to 36 “Enigmas” at once. If the output exceeds a certain level of sense (in this case quite crucially, no letter is every encrypted back to itself) then the settings might be correct and are worth further investigation. This machine has been set up with the top set of “Enigmas” not in place, either to demonstrate the workings or because the machine is set up for one of the more complex deciphering attempts where only some of the banks can be used.


This is the bombe seen from the front

The reason the chap I was talking to really became fascinated with this machine is that, back in about 1999, a home PC programmed to do this work was no faster than the original electro-mechanical machines from 1944 were supposed to have taken. So as an engineer he wanted to help build one and find out why it was so fast. This struck a chord with me because back in the late 1990′s I came across several examples of bespoke computers designed to do specific jobs (either stuff to do with natural gas calorific value, DNA matching or protein folding), but by 2000, 2002 they had all been abandoned as a general PC could be programmed to be just as fast as these bespoke machines – because bespoke means specialist means longer and more costly development time means less bangs for your buck.

Admittedly the Bombe is only doing one task, but it did it incredibly fast, in parallel, and as a part of the whole deciphering process that some of the best minds of their time had come up with (part of the reason the Bletchley Park site was chosen was that it was equidistant between Oxford and Cambridge and, at that time, there were direct train links. {Thanks, Dr Beeching}. ).

Tuning and reliability was as important then as it is now. In the below picture of the back of the machine (sorry about the poor quality, it was dim in that room), you can see all the complex wiring in the “door” and, in the back of the machine itself, those three rows of bronze “pipes” are in fact…Pipes. Oil pipes. This is a machine, they quickly realised that it was worth a lot of effort to keep those disks oiled, both for speed and reliability.


All the workings of the Bombe from the back

Talking of reliability, one other thing my guide said to me. These machines are complex and also have some ability to cope with failures or errors built into them. But of course, you needed to know they were working properly. When these machines were built and set up, they came with a set of diagnostic tests. These were designed to push the machine, try the edge cases and to be as susceptible to mechanical error as possible. The first thing you did to a new or maintained machine was run your tests.

1943, you had awesome parallel processing, incredible speed and test-driven development and regression testing. We almost caught up with all of this in the early 21st Century.

Installing Oracle Enterprise Manager 12c on OL 5.7

I have been closely involved in the upgrade discussion of my current customer’s Enterprise Managers setup from an engineering point of view. The client uses OEM extensively for monitoring, alerts generated by it are automatically forwarded to an IBM product called Netcool.

Now some of the management servers are still on 10.2.0.5 in certain regions, and for a private cloud project I was involved in an 11.1 system was needed.The big question was: wait for 12.1 or upgrade to 11.1?

Migration to Exadata Session at #OOW11

Considering it was the last session of #OOW11 I was surprised to see a sizable number of folks showing up for my 3rd and final session slated for 3 to 4 PM on Thursday. Thank you for attending and for your questions.

Here is the slide deck. Note: please do not click on the link. Instead, right click on it, save the file and open it. It's a Powerpoint show; not a PPT. You can download free Powerpoint player to watch it, if you don't have Powerpoint installed.

Mike Carey: Vicious Circle…

The second in the Felix Castor series by Mike Carey. In Vicious Circle, Felix has to save the ghost of a girl from getting killed (sort of). File under supernatural detective with similarities to The Dresden Files. Pretty cool if you are into this sort of thing, like I am, but not for everyone.

My favorite character has to be Juliette, the succubus. To paraphrase one of her comments regarding attempting to use her abilities on some people suffering from demonic possession, “They should have only been capable of spontaneous orgasm.” It seems demonic possession gets in the way of your average succubus innocently going about their business… :)

Second favorite character has got to be Nikki, a zombie conspiracy theorist. It’s good to know that Zombies care about their appearance too. Nikki tries to prevent his corpse decaying by using industrial air conditioning and avoiding bacterial contamination as much as possible. Nikki is rather surprised by his physical reaction to Juliette, which should be impossible for a zombie as their congealed blood does not flow. I’ll leave it up to you to guess what happened to him. :)

Cheers

Tim…




OOW11: Wednesday…

Wednesday: This was actually my last proper day at Open World. I fly home Thursday morning, effectively missing the last day of the conference. It’s a shame, but it’s the way things worked out and I’m totally burnt out now. :)

Wednesday was definitely “the day after the night before”. I was a little bit under the weather the previous day, so I didn’t feel great on Wednesday morning. Once I got out of the hotel and moving things got a little better. Bagels with cream-cheese in the OCP Lounge helped also. I went to see Cary Millsap speaking about instrumentation, a subject close to my heart. Everyone knows Cary is a great presenter, so I will not big him up any more or his head will pop. :) After that I hung around the RAC Attack in the OTN Lounge, then it was the big keynote. @brost sent Gwen Shapira and I up to the Hilton to watch a stream of the keynote. They didn’t have it there so we had to walk back to Moscone North and sit on the floor to watch it.

Keynote: The keynote was more-or-less what I expected from the ACE Director briefing. There were a few inconsistencies from what we were told, but nothing to write home about. It was all engineered-cloud-exa-grid, with a bit of “everyone else is rubbish” thrown in for good measure. Larry was on good form, but the “live”-ish demo went on a bit too long and I lost interest.

Steve Jobs: I was sorry to hear about the death of Steve Jobs. It’s always sad when people die young. I wish the press would stop making him out to be some sort of Messiah or Saint. He was just a very clever man. Let’s not turn his death into a farce.

Blogger’s Party: After that is was off to the Blogger’s Party, sponsored by Pythian. As with previous years, there were prizes for a number of things, including an iPod Touch for the person who got the most signatures on a Pythian bandana. I made a conscious decision to go for it this year and managed to get a signature from everyone at the event. When it came to the judging I had won, but then felt a little guilty because everybody else hadn’t taken it quite so seriously as me, so I gave the prize to the lady (DBA Kevlar) who came in second place. The sweet smell of victory was easily more important than the prize. :) Thanks to Pythian for another great event.

Once the Blogger’s Party was starting to wind down, most people moved on to the Appreciation Event. I was not really feeling up for it, so I gave my wristband away. I would have only stayed an hour or so, which would have been a bit of a waste. I hope the person who got my wristband ate loads, drank loads and enjoyed Tom Petty and Sting. :) Instead, I went for some food with Chris Muir and Bex Huff, then crashed in my room.

OOW11 Take Home Messages:

  • “Exa” means an engineered solution from Oracle that includes a bit of “magic sauce” software that you can’t run on anyone else’s hardware.
  • Appliance means an engineered solution with stock software running on it. You could build it yourself, but why would you want to?
  • Oracle now do NoSQL (based on the Berkeley DB Storage Engine) as a product. You can get this wrapped up with Hadoop on an engineered system called the Oracle Big Data Applicance. Not sure I will ever touch one of those, but it sounds kinda cool.
  • If BI is your thing, Oracle now provide an Exalytics product that has loads of memory allowing you to do much of your BI workload directly from memory. Once again, sounds cool, but not sure I’ll ever get to touch one.
  • There’s a new version of Grid Control called Enterprise Manager Cloud Control 12c. I guess we now know the next version of the database will be called 12c. :)
  • The movement in the Linux and VM space has got Oracle to the point where they can finally acknowledge that cloud exists and they can build one for themselves. See cloud.oracle.com. If Oracle do this well it could be great for them. If they stuff it up there will be plenty of vendors waiting in the wings to point the finger.
  • Fusion Apps actually exists! Nuff said!
  • Lots of people know about my website, but very few people have got a clue about who I am. That’s the way it should be I guess. :)

Cheers

Tim…




OOW 2011 – Oracle XML DB and Big Data

Last day of Oracle Open World and I am currently attending the last presentations. The first presentation, “Oracle XMLDB: A noSQL Approach to Managing all your Unstructured Data”, deals with the no-SQL approach and using Oracle XML DB in the context of using it with “Big Data”, that is unstructured data. The title of the …

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Why Is My Index Not Being Used No. 2 Solution (The Narrow Way)

As many have identified, the first thing to point out is that the two queries are not exactly equivalent. The BETWEEN clause is equivalent to a ‘>= and <=’ predicate, whereas the original query only had a ‘> and <’ predicate. The additional equal conditions at each end is significant. The selectivity of the original query is basically costed [...]

Adding another node for RAC 11.2.0.3 on Oracle Linux 6.1 with kernel-UEK

As I have hinted at during my last post about installing Oracle 11.2.0.3 on Oracle Linux 6.1 with Kernel UEK, I have planned another article about adding a node to a cluster.

I deliberately started the installation of my RAC system with only one node to allow my moderately spec’d hardware to deal with a second cluster node. In previous versions of Oracle there was a problem with node additions: the $GRID_HOME/oui/bin/addNode.sh script did pre-requisite checks that used to fail when you had used ASMLib. Unfortuntely, due to my setup I couldn’t test if that was solved (I didn’t use ASMLib).

Cluvfy