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the latest business & technology insight & analysis
Deploying PostgreSQL for High Availability with Patroni, etcd and HAProxy – Part 1
Learn how to deploy PostgreSQL for High Availability using Patroni, etcd and HAProxy. This first blog gives an overview and how to setup the OS, Network and install etcd.
Kubernetes Operators pros and cons – the good, the bad and the ugly
Kubernetes Operators offer a way to extend the functionality of Kubernetes beyond its basics. Learn about the pros and cons of using Operators with examples.
Apache Kafka vs Apache Pulsar
This blog describes some of the main differences between Apache Kafka and Pulsar – two of the leading data streaming Apache projects.
Apache Kafka and Regulatory Compliance
How Kafka can help meet regulatory standards and compliance when used as an event broker to Security Information and Event Management (SIEM) systems.
ECS Container monitoring using cAdvisor
In this topic, I will explain how to monitor docker containers running on an ECS cluster. Even though AWS CloudWatch is the preferred tool for monitoring and collecting container metrics, in some scenarios it is required to use alternative solutions.
Incremental backups with rsync and hard links
There are many different options that control the behaviour of the backup process and how it determines what files to copy, link or delete, this blog describes how to build a simple incremental backup solution using rsync and hard links.
Containerized Cassandra Cluster for local testing
A blog on how to build clean and simple containerised Apache Cassandra cluster for local testing, using the official docker image, while preserving the data and having the ability to change any configuration needed.
Cassandra with AxonOps on Kubernetes
How to deploy Apache Cassandra on Kubernetes with AxonOps management tool. AxonOps provides the GUI management for the Cassandra cluster.
Prometheus Blackbox-Exporter – monitoring TLS certificates
A short blog on how to monitor SSL certificate expiry on databases such as Apache Cassandra using Prometheus and visualise on a Grafana dashboard.
Ansible: Variables scope and precedence
Variable scoping can be quite complicated on Ansible and it’s important to know what variable your playbook is going to be using. But sometimes it’s not as easy as it may appear and I’d like to run you through a scenario we found where the results were quite what was expected.
Confirming Kafka Topic Time Based Retention Policies
In this post I will create a Kafka topic and, using the command line tools to alter the retention policy and then confirm that messages are being retained as we would expect them too.
An Interesting Behaviour Observed with Cassandra Concurrent Compaction
One of our customers have a short TTL for an IoT use case. The data model is a standard Cassandra time series with a sensor ID as the partition key and timestamp as the clustering column.
There was a requirement by this customer to retrieve some data that was already purged due to TTL.
Kafka Connect gotcha – SSL
We recently deployed a Kafka Connect environment to consume Avro messages from a topic and write them into an Oracle database. Everything seemed to be functioning just fine until we got a message from the team saying their connectors had suddenly stopped working. On...
Using Molecule to Test Ansible Roles
This blog looks at how to use Molecule to test roles in isolation, as no one is perfect and we all make mistakes but many can be avoid with careful planning.
Ansible Versioning
What is Ansible? If you are reading this blog you probably know what Ansible is but in case this is new to you, let me give you a brief introduction. In the past servers were installed and configured manually. This was quite tedious but ok when there were only a few...
AxonOps Beta Released
We are excited to announce that AxonOps beta is now available for you to download and install!
Digitalis named in top 10 Managed IT Services companies
Digitalis named one of the top 10 Managed IT Services companies of 2018!