Tag Archives: databases

Apache Druid: PostgreSQL as Metadata storage, and replace ZooKeeper with Kubernetes Extensions

5 October 2022

  We continue with a series of posts about Apache Druid. In the first part, we took a look at the Apache Druid itself – its architecture and monitoring, in the second part – we ran a PostgreSQL cluster and set up its monitoring. Next tasks: switch Druid to PostgreSQL as metadata storage instead of Apache Derby… Read More »

PostgreSQL: PostgreSQL Operator for Kubernetes, and its Prometheus monitoring

23 September 2022

  So, we’ve launched Druid, see Apache Druid: Overview, Running in Kubernetes, and Monitoring with Prometheus . So far, a local Apache Derby database is used as the default storage for metadata . Next, we will switch Druid to PostgreSQL, and later we will remove ZooKeeper from the cluster setup. To begin with, let’s start a PostgreSQL cluster in Kubernetes,… Read More »

Apache Druid: overview, running in Kubernetes and monitoring with Prometheus

18 September 2022

 Apache Druid is a columnar database, focused on working with large amounts of data, combining the features and benefits of Time-Series Database, Data Warehouse, and a search engine. The general task is to set up monitoring of the Druid cluster in Kubernetes, so at first, we will see what it is in general and how… Read More »

Tableau: install Tableau Bridge to access a database server in a private network

9 August 2021

 To access a database server, that has no public access (as it must be – access only inside an AWS VPC), Tableau suggests using its tool called Tableau Bridge. The idea is to have a Bridge service running in a network, which has access to a database server via its Private IP. Also, Bridge will… Read More »

Redis: running Master-Slave replication in Kubernetes

29 September 2020

 The task is to spin up a Redis instance in a Kubernetes cluster. Will use the Master-Slave replication setup with Sentinels for monitoring and failover operations. Check the Redis: replication, part 2 – Master-Slave replication, and Redis Sentinel post for more details. Redis cluster vs Redis replication See Redis: replication, part 1 – an overview.… Read More »

Redis: “psync scheduled to be closed ASAP for overcoming of output buffer limits” and the client-output-buffer-limit

26 February 2020

 We have a Redis-cluster with Master-slave replication and Sentinel, see the Redis: replication, part 2 – Master-Slave replication, and Redis Sentinel, Redis: fork – Cannot allocate memory, Linux, virtual memory and vm.overcommit_memory, and Redis: main configuration parameters and performance tuning overview posts. The system worked great until we started using it much more actively. Redis… Read More »

AWS: Redshift – quick start and SQL-workbench connection config

18 October 2019

 Our data-analytics team eventually started to play with an AWS Redshift cluster instead of the MariaDB RDS service. Actually, the current task is to spin up a simple Proof of Concept Redshift’s cluster in the AWS. Let’s do it quickly, without details – if this will go to the Production, I’ll add another post with… Read More »