Pull to refresh
358.01

System administration *

For user to be satisfied

Show first
Rating limit
Level of difficulty

Using a headless browser for WebRTC load tests

Reading time6 min
Views4.1K

In the previous article we went over a load test whose data could be used to choose a load-appropriate server. In the course of the testing, we would publish a stream on one WCS, and we would pick up that stream several times using a second WCS. The acquired results could be used as a basis for decisions on server operability.

Some would (justly) have concerns regarding the possible biases in such a test — after all, one of our servers was used to test another one of our servers. Could it be that we were using a specially optimized code that skewed the results in our favor?

Read more

Choosing a server for 1000 WebRTC streams

Reading time9 min
Views2.2K

In any project, a great deal of importance is placed on the selection of server hardware and WebRTC streaming is no exception. One of the key principles of such a selection is balance – the hardware should be powerful enough to handle the streams with no drops in quality, but not too powerful so as to waste resources. So, how does one choose the right server?

Read more

Application performance monitoring and health metrics without APM

Reading time8 min
Views1.9K

I have already written about AIOps and machine learning methods in working with IT incidents, about hybrid umbrella monitoring and various approaches to service management. Now I would like to share a very specific algorithm, how one can quickly get information about functioning conditions of business applications using synthetic monitoring and how to build, on this basis, the health metric of business services at no special cost. The story is based on a real case of implementing the algorithm into the IT system of one of the airlines.

Currently there are many APM systems, such as Appdynamics, Dynatrace, and others, having a UX control module inside that uses synthetic checks. And if the task is to learn about failures quicker than customers, I will tell you why all these APM systems are not needed. Also, nowadays health metrics are a fashionable feature of APM and I will show how you can build them without APM. 

Читать далее

How to Disable Password Request or Account Password in Windows 10, 8 or 7

Reading time6 min
Views14K
Read this article to learn how to disable password request when booting Windows 10, 8 or 7. How to remove an account password and have Windows boot automatically and right to the desktop screen, without having to enter logins and passwords.

image
Read more →

Linux Switchdev the Mellanox way

Reading time7 min
Views3.2K
This is a transcription of a talk that was presented at CSNOG 2020 — video is at the end of the page



Greetings! My name is Alexander Zubkov. I work at Qrator Labs, where we protect our customers against DDoS attacks and provide BGP analytics.

We started using Mellanox switches around 2 or 3 years ago. At the time we got acquainted with Switchdev in Linux and today I want to share with you our experience.

The magic of Virtualization: Proxmox VE introductory course

Reading time8 min
Views3.2K

Today, I am going to explain how to quickly deploy several virtual servers with different operating systems on a single physical server without much effort. This will enable any system administrator to manage the whole corporate IT infrastructure in a centralized manner and save a huge amount of resources.
Read more →

Ansible: CoreOS to CentOS, 18 months long journey

Reading time4 min
Views1.6K


There was a custom configuration management solution.


I would like to share the story about a project. The project used to use a custom configuration management solution. Migration lasted 18 months. You can ask me 'Why?'. There are some answers below about changing processes, agreements and workflows.

Read more →

How to test Ansible and don't go nuts

Reading time10 min
Views3.7K


It is the translation of my speech at DevOps-40 2020-03-18:


After the second commit, each code becomes legacy. It happens because the original ideas do not meet actual requirements for the system. It is not bad or good thing. It is the nature of infrastructure & agreements between people. Refactoring should align requirements & actual state. Let me call it Infrastructure as Code refactoring.

Read more →

Safe-enough linux server, a quick security tuning

Reading time10 min
Views2.8K
The case: You fire up a professionally prepared Linux image at a cloud platform provider (Amazon, DO, Google, Azure, etc.) and it will run a kind of production level service moderately exposed to hacking attacks (non-targeted, non-advanced threats).

What would be the standard quick security related tuning to configure before you install the meat?


release: 2005, Ubuntu + CentOS (supposed to work with Amazon Linux, Fedora, Debian, RHEL as well)


image

Read more →

Windows Terminal Preview v0.7 Release

Reading time3 min
Views1.7K
Another release is out for the Windows Terminal preview! This release is labeled as v0.7 in the About section of the Terminal. As always, you can download the Terminal from the Microsoft Store and from the GitHub releases page. Here’s what’s new in this release:

Windows Terminal Updates


Panes


You are now able to split your Terminal window into multiple panes! This allows you to have multiple command prompts open at the same time within the same tab.

Note: At the moment, you’re only able to open your default profile within a new pane. Opening a profile of your choice is an option we’re planning to include in a future release!



Read more below.
Read more →

Connect to Windows via SSH like in Linux

Reading time3 min
Views14K
The most depressing thing for me is to connect to Windows hosts. I'm not an opponent or a fan of Microsoft and their's products. Every product has its own purpose. But it is really painful for me to connect to Windows servers, because of 2 points: it is hard to configure (Hi WinRM with HTTPS), and it is really unstable (Hello RDP to VMs across the ocean).

Fortunately, I found the project Win32-OpenSSH. I realized that I want to share my experience with it. I believe it will help somebody and save a lot of nerves.


Read more →

Who is stealing virtual CPU time?

Reading time10 min
Views12K


Hi! In this article, I want to explain, in layman’s terms, how steal appears in VMs and tell you about some of the less-than-obvious artifacts that we found during research on the topic that I was involved in as CTO of the Mail.ru Cloud Solutions platform. The platform runs KVM.
Read more →

Free Wireguard VPN service on AWS

Reading time9 min
Views68K

Free Wireguard VPN service on AWS


The reasoning


The increase of Internet censorship by authoritarian regimes expands the blockage of useful internet resources making impossible the use of the WEB and in essence violates the fundamental right to freedom of opinion and expression enshrined in the Universal Declaration of Human Rights.


Article 19
Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers.

The following is the detailed 6 steps instruction for non-IT people to deploy free* VPN service upon Wireguard technology in Amazon Web Services (AWS) cloud infrastructure, using a 12 months free account, on an Instance (virtual machine) run by Ubuntu Server 18.04 LTS.


I tried to make this walkthrough as friendly as possible to people far from IT. The only thing required is assiduity in repeating the steps described below.

Read more →

Authors' contribution