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Showing posts from April, 2021

Accessing MySQL NDB Cluster Database From MySQL Connector/Python

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In this post, we will see how to access database and its objects in MySQL NDB Cluster from Connector/python program. I assume that the reader has some basic understanding of python language and MySQL NDB Cluster. Let’s create a MySQL NDB Cluster with the following environment: MySQL NDB Cluster version (Latest GA version) 1 Management node 4 Data nodes 1 Mysqld server Configuration slots for up to 4 additional API nodes Connector/Python version (Latest GA version) Note: Python software must be installed on the same host where we are planning to install MySQL Connector/Python. MySQL NDB Cluster Architecture: Let’s look at the MySQL NDB Cluster architecture. MySQL Connector/Python is one of the connector provided by MySQL to access data in the database. Connector/Python is a library written in python that can talk to the MySQL server. It is a self-contained driver i.e. Connector/Python does not require the MySQL client library or any Python modules outside the standard library. From NDB

How to do online configuration changes in MySQL NDB Cluster (Part I)

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In this blog, we will discuss about how to perform cluster configuration changes while cluster is up and processing transactions (online). In MySQL NDB Cluster, configuration data is parsed and distributed by the management server (MGMD) nodes. Users supply an input text file (commonly known as config.ini) which describes cluster topology, resource usage limits and other parameters. The MGMD nodes parse this file, combine it with designed in defaults and serve the resulting configuration to other node types (data nodes, api nodes), when they connect. Reasons for changing configuration might include: - Increased resource usage limits (Data memory, IndexMemory, buffers) - Adding a new configuration parameter(s) i.e. enabling a new feature - Unsupported configuration parameter taken out during downgrade to lower version i.e. disabling a feature - etc .. MySQL Cluster nodes pick up configuration changes when restarted, so it is generally necessary to restart each node in turn so that new c

MySQL NDB Cluster Installation Through Docker

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In this post, we will see how to setup MySQL NDB Cluster from a docker image. I assume that the reader has some basic understanding of docker and its terminology. Steps to install MySQL NDB Cluster: Let's create a MySQL NDB Cluster with the following environment: MySQL NDB Cluster version (Latest GA version) 1 Management Node 4 Data Nodes 1 Mysqld Server Configuration slots for upto 4 additional API nodes  Note: Docker software must be installed and running on the same host where we are planning to install MySQL NDB Cluster. Also make sure we have enough resources allocated to docker so that we shouldn’t face any issues later on. Step 1: Get the MySQL NDB Cluster docker image on your host Users can get the MySQL NDB Cluster image from github site ( link ). Then select your required cluster version for download. Note: By default MySQL NDB Cluster 8.0 GA version image docker will pull or by mentioning tag:latest also point to latest cluster image which is 8.0 at the moment. If us