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Introduction In this article, I would be describing the ES(Elasticsearch) terms necessary for understanding the calculation. After acquainting you about Amazon ES, I will tell you about how to calculate the minimum storage size and number of shards required for Elasticsearch with example. Elasticsearch Elasticsearch is an open-source analytics engine for use cases such as log analytics, real-time application monitoring and clickstream analytics. Node A Node is an EC2 instance. Elasticsearch Cluster Elasticsearch Cluster is a collection of one or more node(server) that holds the entire data and provides federated indexing and search capabilities across all nodes. Amazon Elasticsearch Amazon Elasticsearch is a managed service, which makes it easy to deploy, operate and scale Elasticsearch clusters in the AWS cloud. What Amazon Elasticsearch manages Amazon ES provisions all the resources for the Elasticsearch cluster and launches it.  It autom...

Before 15 August 2019, it was very difficult to debug and do root cause analysis of an unresponsive or unreachable AWS EC2 instance. Generally, the operating system gets crashed and rebooted when a kernel panic(in case of Linux) or stop error(in case of Windows) is triggered. The operating system can be configured to perform diagnostics tasks on kernel panic or stop error such as generating memory dump files for root cause analysis and debugging. On 15 August 2019, Amazon introduced a simple API to trigger a kernel panic  by sending   diagnostic Interrupt  to an unresponsive instance, which in turn can direct the operating system to perform tasks like creating a crash dump, loading the secondary kernel, or obtaining a call trace. Some concepts about operating system interrupt An interrupt in the operating system is the highest priority signal send from hardware or software to the processor to process. There are two types of interrupts that occur in the op...

Before going into details of how to use Athena service to query S3 bucket, let me introduce you all about what AWS Athena is actually. What is AWS Athena? Athena is query service which uses standard SQL to fetch data from s3 bucket. Use case Suppose there are 3 files stored in s3 bucket (athena-sample-bucket) samplefile1.log.gz(1gb) samplefile2.log.gz(700mb) samplefile3.log.gz600mb Each log.gz file mentioned above has log data in CSV structure with comma-separated fields. Now, what will we do if we want to get data record which belongs to one of the files in s3 bucket? Approach 1 Read each file in s3 bucket and write logic to search the record which we want to fetch. This approach is slow and complex. Approach 2 Use AWS Athena service to query required record from s3 bucket. Athena uses standard SQL. Let's use Athena step by step Goto services section of AWS website and search for Athena. Select Athena service from the search result. This is how i...

When you publish any Android App on play store, the review process can treat your App as spam. Here is the list of spams that google play store review system protects the users against: Message Spam Webviews and affiliate spam Repetitive content Made for ads Reference:  https://play.google.com/about/spam-min-functionality/spam/

There are few things you should avoid while publishing App on play store which uses webview. Following are the reasons your App would get suspended to be published on play store. An app whose primary purpose is to drive referral traffic to a website to receive credit for user sign-ups or purchases on that website. Apps whose primary purpose is to provide a webview of a website without permission. For e.g.  Your app is called “John’s Movie Search App” and it simply provides a webview of IMDb.