Chris on January 17th, 2011

Useful guide to Mac troubleshooting. I wasn’t sure what the difference between the gray apple screen and the grey apple screen with the spinning gear.

Mac 101: Whats happening when your Mac is starting up?.

Chris on November 18th, 2010

1) The bandage was wound around the wound.
2) The farm was used to produce produce.
3) The dump was so full that it had to refuse more refuse.
4) We must polish the Polish furniture.
5) He could lead if he would get the lead out.
6) The soldier decided to desert his dessert in the desert.
7) Since there is no time like the present, he thought it was time to present the present.
8 A bass was painted on the head of the bass drum.
9) When shot at, the dove dove into the bushes.
10) I did not object to the object.
11) The insurance was invalid for the invalid.
12) There was a row among the oarsmen about how to row.
13) They were too close to the door to close it.
14) The buck does funny things when the does are present.
15) A seamstress and a sewer fell down into a sewer line.
16) To help with planting, the farmer taught his sow to sow.
17) The wind was too strong to wind the sail
18) After a number of injections my jaw got number.
19) Upon seeing the tear in the painting I shed a tear.
20) I had to subject the subject to a series of tests.
21) How can I intimate this to my most intimate friend?
22] I want it to be on record that I wll record my record.

I’m going to add this site to my blogroll. The author is one of VMWare’s R&D honchos.

Interesting tid-bit on how to DOS Google if you’re so inclined.

Some of the search queries can cause huge IO. One example Jeff gave is “circle of life” as one phase enclosed in double quotation marks. It could incur 30GB I/O before. As I just searched on Google, the phrase is now a song name. I bet it’s now in Google’s cache server.

When there are so many servers to manage, something unique happened. Jeff mentioned an interesting phenomenon called “query of death.” If a query can causes a server to crash, then it can crash all other servers because the software stack is the same. To avoid large scale of crashes, they used canary request which is first sent to one machine. If it’s good, then send it to the rest of machines; otherwise reject the request after failing several times. It of course adds a little delay but far better than large scale system crash. Of course, you need to log down the query and found out why it crashed software as a process of continuous improvement. Jeff didn’t mention this, but I bet Google did that.

via DoubleCloud » What Lessons You Can Learn from Google on Building Infrastructure.

So, I wonder what the I/O load is on google if I did a search on:

“Ubuntu Private Cloud Prince William Engagement” or “MySQL Replication Senator McConnell Earmark ban”
Pick any two other totally different subject and combine them into a single query.

Chris on October 26th, 2010

I’ll admit, we use Netflix streaming and Netflix a lot. I just don’t see the NetFlix catalog as being big enough to encompass 20% of consumer bandwidth.

Netflix streaming consumes 20pct of download throughput during weekday primetime hours

via How Google TV Could Hand Netflix The Entire Streaming Universe | paidContent.

Chris on October 25th, 2010

I find it fascinating what kind of electronic fingerprints are left by modern technology. From password guessing based on the intervals between packet transmission to detecting minute gaps in an analog conversation to determine a call originated in Nigeria and not New York.

Voice-routing call fingerprint system fights ‘vishing’ • The Register.

Chris on October 12th, 2010

Stephen Fleming, a former Venture Capitalist, who now handles commercialization of intellectual property for Georgia Tech, penned a good blog post on UGA’s expressed interest in creating an engineering program.

Campus rivalry aside, Fleming makes the case that the money could be best spent elsewhere. More funding for K-12 Math and Science, expanding the Georgia Technical College System, or expanding the instructional facilities at Georgia Tech, would cost a fraction of the tens of millions of dollars it would cost to create an engineering program from scratch in Athens.

In addition, unless UGA planned to drastically lower its admission standards, it wouldn’t be admitting a whole lot more Georgia High School graduates than GaTech already does.

At a time when the Georgia budget is stretched so thin, is it really worth spending millions of dollars to boost the prestige of a University President?

Finally, he takes aim at the You-Must-Have-A-College-Degree-To-Succeed myth, and makes the case for more technical education:

If you’re 18 years old and have no idea what you want to do with your life… major in engineering! I don’t really care what branch of engineering. The interesting stuff happens at the edges, anyhow (merging electrical engineering with biomedical engineering leads to implantable heart monitors, etc.). But, engineering remains rigorous, engineering remains grounded in reality, and you can’t gobbledygook your way to an engineering degree. If you get the design wrong, or flub the calculations, the bridge will fall down, and not all the neo-Marxist deconstructionist twaddle in the world will change that.

Engineering will kick your butt, but you will learn something… and you’ll learn how to learn. (Something that cannot be said for the earnest young undergraduate who can regurgitate the entire works of Jacques Derrida, but whom I wouldn’t hire as night watchman in a cement factory.) And that will set you up for a lifetime of fulfilling and successful work, whether you choose to continue in engineering, or switch to medicine, or law, or farming, or building electric guitars.

Chris on September 20th, 2010

$1500 for a new ESXi server for vSphere 4.1 is a bit high. Unlike this guy, I have a lab in the basement so decibles aren’t as important as capex and opex costs.

Plus, to have a lab in the basement where I can do things with a cluster would require two of these beasties. Running a second on the iMac i7 probably won’t cut it. Last time I needed a lab for something it was because a network change crapped out 1/4 of my primary vSwitch.

I think I’d like to do a mock-up of the vCluster configs we have at work, then randomly shoot components to see how it fails. The network change issue was unexpected. Losing 1 out of the 4 strands of the portchannel going to a vswitch should not have cause the outage, however brief it was.

Meet My ESXi Server, the BabyDragon. | Error404 – Its A Blog.

Chris on September 3rd, 2010

VMWare ESXi 4.1 looks incredibaly interesting. It has better monitoring functions, better authentication integration and other cool features. I need to upgrade.

Sadly, the CPU in my current VMWare host doesn’t support the Intel vt extensions so it won’t run 64bit VMs, and it won’t support ESXi 4.1. So I’m looking at having to drop at least a grand to get a new server capable of running the latest VMWare. My Media Center PC could do it, but sadly, the Shuttle PC I was going to make my Media Center PC has a dead power supply, and Shuttle doesn’t carry accessories anymore.

Anyway, once the iTV ships, I can retire the Media PC and convert it to an ESXi host. Once I do that, here are a list of Virtual Appliances I want to play with:

Chris on August 28th, 2010

When I decided to un-jailbreak my iPad and remove Cydia, I did a “Erase all Content and Settings” via the Apple Settings App. This however caused the iPad to no longer boot. Apparently it erased lots of data, but it did not restore some of the boot processes.

On a Cydia jailbroken iPad, there are two bars of pixled colors during the boot apple screen. These were present on the boot screen after I erased all the content. Eventually the iPad boot up sequence would time out and the iPad would reboot and fail again. I had effectivly bricked my iPad.

Digging around in google didn’t really provide much guidance. I did finally find a document provided  by apple which provides instructions on how to restore a backup from iTunes.

iPad: Unable to update or restore.

Chris on July 21st, 2010

Preseeds are poorly documented. This is a note to myself on how to reproduce an install

sudo apt-get install debconf-utils # It is part of the debconf-utils package.
debconf-get-selections –installer > somefile.txt
debconf-get-selections >> somefile.txt “

via [ubuntu] preseeding installation 8.10 – how to preseed “encrypted directory” prompt? – Ubuntu Forums.