As you can see in the previous blog , Hadoop successfully failover , but it fails to failback. Our solution to this problem is this: The failover will be done as described in the post a couple of ...

I’ve been trying to cause the NN to recognize that it is inconsistent and turn to the SNN for data. Scenario 1: Will the NN Recognize that its data is not up-to-date? (No) Started with NN on s...

We’ve decided to test using linux HeartBeat together with hadoop , to enavle failover (and failback) capacbilities. Infrastructure: Take 3 Servers : A is the NN , B is the SNN and will be later us...

Hbase configuration and running is very similar to hadoops. Not surprisingly , they also have a nice Getting Started page. The tricky part , though , is to understand what the hell do they mean wit...

First thing : It works. If you’re getting a lot error messages and you start thinking “well , maybe it’s crap. still 0.18 can’t be that good a version” Stop. It works. Hadoop has a very good Gett...

We have a very large amount of relatively small files (~5k avg , 41k max , 0k min) , that we access a lot (20M times a day) for various computations. Currently , all the data is stored on a single ...