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Getting started with Cassandra

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With the motivation from today’s public news on Twitter’s move from MySQL to Cassandra, my own skills desire following in-depth discussions at last November’s Open SQL Camp to consider Cassandra and yesterday’s discussion with a new client on persistent key-value store products, today I download installed and configured for the first time. Not that today’s news was unexpected, if you follow the Twitter Engineering Open Source projects you would have seen Cassandra as well as other products being used or evaluated by Twitter.

So I went from nothing to a working Cassandra node in under 5 minutes. This is what I did.

  1. While I knew this was an Apache project, a Google Search yields for me the 3rd link for the The Apache Cassandra Project at http://incubator.apache.org/cassandra/. Congrats for Cassandra now a top level Apache Project. This url will update soon.
  2. Download Cassandra. Hard to miss with a big green button on home page. Current version is 0.5
  3. I read Getting Started, which is the 3rd top level link on menu after Home and Download. Step 1 is picking a version which I’ve already done, Step 2 is Running a single node.
  4. The Getting Started indicated a problem on Mac OS X for the required minimum Java version. I was installing on Mac OS X 10.5 and CentOS 5.4. I’ve experienced this Java 6 default path issue before. Set my JAVA_HOME and PATH accordingly (after I updated the wiki with correct value)
  5. I extracted the tar file, changed to the directory and took at look at the README.txt file. Yes, I always check this first with any software and relevant because it includes valuable instructions on creating the default data and log directories.
  6. Start with bin/cassandra -f. No problems!
  7. I then followed the instructions from the link in Step 2 with the CassandraCli. This tests and confirms the installation is operational.

Ok, a working environment. I’ve now installed on a second machine and tested however I now need to configure the cluster, and the documentation is not as straightforward. Time to try out Google again.

On a side note, this is one reason why I love Open Source. I followed the instructions online and found a mistake in the Mac OS X path, I simply registered and corrected providing the benefit of my experience for the next reader(s).

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MiFi Introduction

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My first news of the Verizon MiFi was via Twitter when @DonMacAskill said “Think my iPhone 3G via MiFi is faster than AT&T 3G. Should I carry both all the time now?”

A few reviews later such as Verizon Mifi: Personal Wi-Fi Coming this Month and Verizon MiFI a personal broadband bubble to believe in but this on my to buy tech list. I presently have a Generation 1 Day 1 iPhone, so no 3G there.

In summary, this device is the size of 5 credit cards, weighs not much more then 5 credit cards and enables 3G Wireless broadband access on the Verizon network, and also doubles as a WiFi router for up to 5 other devices.

I have been procrastinating about getting one, the combination to do urgent work at midnight on the AirTrain and NY Subway (the above ground part), and then the following day on a client site when the internet was flaky convinced me to get one.

The purchase process was relatively straightforward, except the usual credit check woes for an Australian living in this country. The installation and use, well that’s another painful story to share.