Do you know what are SiliconAngle and Wikibon project? If not – check them out soon. These guys have a vision about next generation media coverage. I would call it ‘#1 no-BS Silicon Valley media channel’. These guys are running professional video journalism with a very smart technical setup. And they aren’t your typical loudmouth from the TV: they use and grok technologies they are covering. Say, they run Apache Solr in house for real-time trends processing and searches. Amazing. And they don’t have teleprompters. Nor screenplay writers. How cool is that?
At any rate, I was invited on their show, theCube, last week at the last day of Hadoop Summit. I was talking about High Availability issues in Hadoop. Yup, High Availability has issues, you’ve heard me right. The issue is the lesser than 100% uptime. Basically, even if someone claims to provide 5-9s (that is 99.999% uptime) you still looking at about 6 minutes a year downtime of the mission critical infrastructure.
If you need 100% uptime for you Hadoop, then you should be looking for Continuous Availability. Curiously enough, the solution is found in the past (isn’t that always the case?) in so called Paxos algorithm that has been published by Leslie Lamport back in 1989. However, original Paxos algorithm has some performance issues and generally never been fully embraced by the industry and it is rarely used besides of just a few tech savvy companies. One of them – WANdisco – has applied it first for Subversion replication and now for Hadoop HDFS SPOF problem and made it generally available is the commercial product.