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.

AWS: VPC peering DNS resolution and DNS settings for OpenVPN Access Server

17 May 2019
 

 We have a VPC with OpenVPN Access Server running. This VPC is connected with other VPCs in our AWS account. The issue is that currently when a user is connected to VPN for the DNS resolution into EC2 instances private IPswe are using dnsmasq service on the VPN-host which has a /etc/dnsmasq.hosts file where are manually… Read More »

AWS: MariaDB RDS – kill: You are not owner of thread

14 May 2019
 

 We have AWS RDS with MariaDB. The error below and its solution aren’t specific to AWS RDS and MariaDB. The next error appears during attempt to kill() a thread in MySQL: The solution is to use the mysql.rds_kill() procedure instead: Execute it: For Azure MySQL, there is a similar procedure mysql.az_kill(). Done.

Bitwarden: an organization’s password manager self-hosted version installation on an AWS EC2

1 May 2019
 

 We consider Bitwarden as a passwords keeper for our project with the main goal to have an ability to have separated access to secrets by user roles and/or ACLs. I.e. Pass or KeePass are good for self-usage by one person but they have no main things – a normal web-interface and role-based access to data.… Read More »

Authy: step by step Multi-Factor Authentication configuration for Github and AWS

17 April 2019
 

  I’m sure that using MFA (Multi-Factor Authentication) today is oblivious. For 2FA (2-Factor Authentication) the most used method is TOTP – Time-based One-time Password, when alongside with the common login:password also needs to enter a code generated by a device or software. The most known implementation is Google Authenticator but also there is a… Read More »

Jenkins: a job to check a Github organization’s public repositories list

16 April 2019
 

 Proceeding with a Github repositories checker. To recall: the idea is to have such a check in case if somebody from developers accidentally will share our project’s private repository as public, or will create a public repository instead of making it as a private one – we will get a Slack alarm about such a… Read More »

Redis: Sentinel – bind 0.0.0.0, the localhost issue and the announce-ip option

10 April 2019
 

 Originally, in a Sentinel’s configs, I have used the bind 0.0.0.0 to make them accessible from external hosts. Because of this when I started rolling out this setup on a real environment faced with an issue when Sentinels could not determine a Master host and other Sentinel hosts. In this post – such an issue… Read More »

MySQL/MariaDB: like Petya ransomware for MySQL and ‘root’@’%’ access

3 April 2019
 

  This story happened on 10/06/2017, adding this post in English now. The original post (Rus) was written almost right after the well-known Not a Petya attack in Ukraine – that’s why it’s used in the title. I had a new project assigned to me. When I started its existing setup investigation – was just… Read More »

Kubernetes: running Minikube on Arch Linux

27 March 2019
 

 Minikube – a utility to run a Kubernetes cluster locally on your PC. It can use Virtualbox, VMware, Hyper-V etc hypervisors which will be used to create a virtual machine with a Kubernetes cluster. Minikube is a great tool for developers or DevOps engineers to test deployments/services etc without the need to create and configure… Read More »

What is: chroot – the system call and utility in Linux

23 March 2019
 

 chroot() was added to the Version 7 Unix in 1979 and used for filesystem isolation. In fact, it’s the predecessor of the whole current containerization idea, just now there are namespaces and cgroups are used while earlier chroot was used to create an environment which is isolated from a host and can be used for… Read More »