Category Archives: Virtualization

In computing, virtualization refers to the act of creating a virtual version of something, including virtual computer hardware platforms, storage devices, and computer network resources.

Kubernetes: part 5 — RBAC authorization with a Role and RoleBinding example

26 March 2020
 

 The next task is to add a new user who will have access to check pods state and watch logs – any other operations must be prohibited. AWS EKS uses AWS IAM for authentification in a Kubernetes cluster (check the Kubernetes: part 4 – AWS EKS authentification, aws-iam-authenticator and AWS IAM post for details), bot… Read More »

AWS: CloudFormation – Nested Stacks and stacks parameters Import/Export

29 February 2020
 

 Nested Stacks in AWS CloudFormation are stacks, created from another, a “parent”, stack using AWS::CloudFormation::Stack. The main idea behind the Nested Stacks is to avoid writing superfluous code and to make templates reusable. Instead, a template is created only once, stored in an S3 bucket, and during stacks creation – you just refer to it.… Read More »

Linux: PHP-FPM, Docker, STDOUT and STDERR – no an application’s error logs

24 February 2020
 

 We have a Docker image with NGINX, PHP-FPM, and Supervisor. In the same image, we have our PHP application included, which outputs its errors to the /dev/stderr as per its php.ini file: … [global] error_log=/dev/stderr … The problem is, that if run kubectl logs –  there will be no error output from the application. So,… Read More »

Kubernetes: running metrics-server in AWS EKS for a Kubernetes Pod AutoScaler

15 February 2020
 

 Assuming, we already have an AWS EKS cluster with worker nodes. In this post – we will connect to a newly created cluster, will create a test deployment with an HPA – Kubernetes Horizontal Pod AutoScaler and will try to get information about resources usage using kubectl top. Kubernetes cluster Create a test cluster using… Read More »

Debian: php7.3-curl : Depends: libcurl3 (>= 7.44.0) but it is not installable

23 January 2020
 

 We have a Jenkins job that runs a Docker container to build a PHP-application based on the Yii framework. Suddenly during the build, we got an error: … Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required… Read More »

Nextcloud: running in Docker Compose on Debian with Let’s Encrypt SSL

30 November 2019
 

 I while ago I’d tested the Nextcloud, see the NextCloud: installing server on Debian behind NGINX with PHP-FPM and client on Arch Linux post. In general, it looks good, so it’s time to try to run in a production environment and finally migrate from Dropbox to it. Today, let’s spin up a Nextcloud instance using… Read More »

AWS: RDS Certificate Authority SSL certificate upgrade

22 November 2019
 

 We started receiving emails from AWS with notifications to update RDS Certificate Authority certificates. It’s time to do it, so let’s start from our Dev, then will repeat on Staging and Production environments. W eare using common AWS RDS MariaDB instances, and the upgrade documentation is available here>>>. The process itself is really simple and… Read More »

dnsmasq: AWS – “Temporary failure in name resolution”, logs, debug and dnsmasq cache size

28 October 2019
 

 We are using AWS VPC DNS and sometimes facing with errors like “php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution“. The only advice from AWS tech. support was to configure a local dnsmasq service to act as a local DNS cache, but I did this already year ago and this issue happens once in 1-2-3… Read More »