Category Administration
Aloha, people! My name is Oleg Anastasiev, I work at Odnoklassniki in the Platform team. And besides me, a lot of iron works in Odnoklassniki. We have four data centers, they have about 500 racks with more than 8 thousand servers. At a certain point, we realized that the introduction of a new control system would allow us to load equipment more efficiently, facilitate […]
How would you feel if, one fine summer day, the data center with your equipment looked like this? Hi all! My name is Dmitry Samsonov, I work as a leading system administrator at Odnoklassniki. The photo shows one of the four data centers where the equipment serving our project is installed. Behind these walls there are about 4 thousand pieces of equipment: servers, […]
Transcript of Ilya Kosmodemyansky's 2015 report "Linux Tuning to improve PostgreSQL performance" Disclaimer: Please note that this report is dated November 2015—more than four years have passed, and a lot of time has passed. The version 9.4 discussed in the report is no longer supported. Over the past four years, five new PostgreSQL releases have been released, as well as 15 kernel versions. LinuxIf you rewrite […]
If you're working with Kubernetes, then kubectl is probably one of your most used utilities. And whenever you spend a lot of time working with a certain tool, it's worth learning it well and learning how to use it effectively. The Kubernetes aaS team from Mail.ru has translated an article by Daniel Weibel, in which you will find tips and tricks for working […]
The other day in the Netherlands hosted "Eurovision" for neural networks. The first place was given to a song based on the sounds of koalas. But, as is often the case, it was not the winner who riveted everyone's attention, but the performer who took third place. The Can AI Kick It team presented the song Abbus, which is literally permeated with anarchist, revolutionary ideas. Why did it happen, what does Reddit have to do with […]
BLE under the microscope (ATTs GATTs…) Part 1, overview Quite a long time has passed since the first specification for Bluetooth 4.0 was released. And, although the topic of BLE is very interesting, it still repels many developers due to its complexity. In my previous articles, I mainly considered the lowest level of the Link Layer and the Physical Layer. […]
In microservice architecture projects, CI/CD is moving from a nice opportunity to a must. Automated testing is an integral part of continuous integration, a competent approach to which can give the team many pleasant evenings with family and friends. Otherwise, the project runs the risk of never being completed. It is possible to cover the whole microservice code with unit tests […]
I am publishing the first chapter of lectures on the theory of automatic control, after which your life will never be the same. Lectures on the course "Management of Technical Systems", reads Kozlov Oleg Stepanovich at the Department of "Nuclear Reactors and Power Plants", Faculty of Power Engineering, Moscow State Technical University. N.E. Bauman. For which he is very grateful. These lectures are only being prepared for publication in book form, and […]
Less than 10 years later, the developers of RoS (in stable 6.47) added functionality that allows you to redirect DNS queries according to special rules. If earlier it was necessary to dodge with Layer-7 rules in the firewall, now it is done simply and elegantly: /ip dns static add forward-to=192.168.88.3 regexp=".*\.test1\.localdomain" type=FWD add forward -to=192.168.88.56 regexp=".*\.test2\.localdomain" type=FWD My happiness knows no bounds! […]
In this article, we will analyze the passage of not just a machine, but an entire mini-laboratory from the HackTheBox site. As stated in the description, POO is designed to test skills at all stages of attacks in a small Active Directory environment. The goal is to compromise an available host, escalate privileges, and eventually compromise the entire domain by collecting 5 flags in the process. Connection […]
Today we are sharing a selection of administration courses from the Education section on Habr Career. Free in this area, frankly, not enough, but we still found 14 pieces. These courses and video tutorials will help you gain or improve your skills in cybersecurity and system administration. And if you saw something interesting that is not in this issue, share the links […]
Distance learning is now becoming more popular for all of us for obvious reasons. And if many readers of Habr know about various kinds of courses in digital specialties - software development, design, product management, etc., then the situation is a little different with lessons for the younger generation. There are many services for online lessons, but what to choose? In February, I was evaluating different platforms, and […]