Data Drudgery

It took me from late morning to evening to be able to connect to MySQL Server 5.7 from PHP 7.0 over SSL on an EC2 machine with Amazon Linux OS image. There were many steps and each had its own challenge. Below I am mentioning the steps and how I worked around the problems. Step 1: Upgrading PHP from 5.6 to 7.0. First one has to remove the existing version of PHP and then install a newer version. I tried installing version 7.1 first but I ran into dependency issues like libpng15 for which the easiest way to install is to build from source. To avoid falling into this dependency cycle, I tried installing version 7.0 and this one installed smoothly. # Remove PHP 5.6 [ec2-user@ ~]$ sudo yum remove php5* # Install PHP 7.0 [ec2-user@ ~]$ sudo yum install php70 php70-mysqlnd php70-imap php70-gd \ php70-pecl-memcache php70-pecl-apcu Step 2: Upgrading MySQL server from 5.6 to 5.7. The default repos did not have MySQL 5.7. I also could not install it by adding repos, as ev...

In a previous blog we saw how to install Spark on EC2. I am doing this so that I can save on the cost of EMR on top of EC2 which can be over two thousand USD per year for large instances. Even for smaller instances the savings can be up to 30%. In this blog entry we will see how to run a spark job on a cluster. You can run Spark jobs in local mode where the job run locally on a single machine. To run Spark jobs on a cluster, a cluster manager is required. Spark has its own simple cluster manager, and its called the Standalone cluster manager. Industry applications usually swap the Standalone cluster manager for either Apache Mesos or Hadoop YARN .For this example I have setup a small cluster with one t2.micro instance (1 vCPU, 1G), which will act as the master and two m3.medium instances (1 vCPU, 3.7G) which will be the workers. Before setting up the cluster make sure that the cluster security group has sufficient permissions and the master and slaves can communicate with each...

This is an account of setting up Spark on my small EC2 cluster of two m3.medium spot instances. Spot instances are good way of saving on cost of on demand prices, and you also get the option of retaining your instances till the spot prices are below your chosen maximum bid. There are many well written guides about setting up Spark on an EC2 cluster but I still got stuck at a few places. I will be describing those here, along with what was the reason for getting stuck. This will be helpful for those who face similar problems. I will not go into the details of each step, but delve into details of only the troubleshooting parts.  Step 1: Create an IAM role for EC2 service role. This step is not required for setup of Spark. This is required only when accessing other AWS services. Step 2: Create security group with SSH access from your local work machine. This step is crucial, as without this we cannot SSH into the EC2 machine. Step 3: Launch EC2 instances with IAM ro...