Developers Club geek daily blog

Systemd and containers: acquaintance to systemd-nspawn

2 years, 7 months ago

Containerization today — one of the most actual subjects. The number of publications about such popular tools as LXC or Docker, is calculated by thousands if not in tens of thousands.
In this article we would like to discuss one more solution about which publications in Russian meanwhile a little. It is about systemd-nspawn — the tool for creation of the isolated environments which is one of the systemd components. And fixing of systemd as the standard in the world of Linux — already come true fact. In the light of this fact there are all bases to believe that soon scope of systemd-nspawn will significantly extend, and  it is worth getting acquainted with this tool closer already now.

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Ansible 2.0 beta 2

2 years, 8 months ago

 We already wrote with Ansible configurations about management system two years ago. We actively use it in own practice and we watch closely all changes and updates.
 Of course, we  could not disregard the following news:  the second beta of Ansible v2.0 was published. The draft Ansible v2.0 option was placed on GitHub for a long time, and now at last more or less stable beta release appeared.

In this article we will tell about the most significant innovations in the second version.

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Remote node of K-root in Selektel

2 years, 9 months ago

The increase in number of Internet users in developing countries involves need of development of the corresponding infrastructure, including DNS servers.

For the last some years the geography of the root DNS servers was significantly expanded. Still quite recently working nodes of root servers have been generally concentrated in Europe and the USA, today they appear in the countries of Asia, Africa, South America. This year one of nodes of the K-Root server has been set even in Iran from which up to the end western sanctions are still not removed.

The question of expansion of root DNS system is actual and for Russia. Certain contribution to its solution managed to be made also to us: in August of this year one of nodes of the root K-Root DNS server has been placed with us. In this article we will tell about its architecture and about participation in competition on its placement.

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Audit of system events in Linux

2 years, 9 months ago
Linux Audit

One of the tools allowing to raise the security level in Linux is the audit subsystem. With its help it is possible to receive detailed information on all system events.
It does not provide any additional protection, but provides detailed information on violations of safety on the basis of which it is possible to take specific measures. We will consider features of work with audit subsystem in this article.

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Reservation of router with use of the VRRP protocol

2 years, 10 months ago

We have started new service: reservation of router with use of the VRRP protocol ( abroad it is known under the name failover IP. As far as we know, in Russia to us anybody similar did not do anything. Service will be interesting first of all to those who would like to provide constant availability of business and significant Internet resources, but thus does not possess for this purpose sufficient technical opportunities: has neither own autonomous system, nor the block of IP addresses, connections to providers under the BGP protocol.
  We will in detail tell about features of its technical implementation in this article.

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Work with API Vscale

2 years, 10 months ago

 We have only casually mentioned in the previous article that Vscale is equipped with simple and convenient API which significantly simplifies interaction of developers with infrastructure. Today we will tell about opportunities and the API functions in more detail.

Vscale API is located at the address
With its help it is possible to execute the same actions, as through control bar:

  •  to create and delete servers;
  • to reconfigure servers on more productive and to pass to other tariff plan;
  •  to disconnect, include and reboot servers;
  • to receive information on payments and write-offs from the account;
  • to work with tiket-system (to create new tiketa, to send comments, to close tiketa).

Interaction is carried out by means of standard HTTP requests. For data exchange the JSON format is used.
 In case of successful processing of request of API will return object model in the JSON format. At emergence of error you receive its code and the short description (it contains in the heading Vscale-Error-Message).

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Vscale: we create the first server

2 years, 11 months ago

Vscale — the cloudy provider, which users can create for read seconds cloud servers with required characteristics. Procedure of creation of the new server is extremely simple. In this article we will paint it in detail, on steps.

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Vscale: cloud servers

2 years, 11 months ago

We started new service under the name Vscale. Its users can create virtual servers in a cloud and manage them via the convenient graphic interface. Service is equipped with the simple API allowing to automate management and scaling.

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Management of logging in systemd

2 years, 11 months ago
Systemd Journal

The demon of initialization of systemd de facto already became the standard in modern Linux-systems. Have passed many popular distribution kits to it: Debian, RHEL/CentOS, Ubuntu (starting with version 15.04). In systemd other is used essentially ( in comparison with the traditional syslog tool) approach to logging.
 Centralization is its cornerstone: the dedicated component of journal collects all system messages (the message of kernel, different services and applications). Thus specially it is not necessary to configure sending logs: applications can simply write to stdout and stderr, a journal will save these messages automatically. Work in such mode is possible and with Upstart, but it saves everything log in the separate file whereas systemd saves them in binary base that significantly simplifies systematization and search.

Storage of logs in binary files also allows to avoid difficulties with use of parsers for different types of logs. If necessary log it is possible to convert without problems in other formats (in more detail about it it will be told below).
Journal can work as together with syslog, and completely to replace it.
For viewing of logs the utility of journalctl is used.  With it we will tell about features and subtleties of work in this article.

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Service start? Virtual private cloud?

3 years, 2 months ago

About service? Virtual private cloud? (Virtual Private Cloud, VPC) we already wrote. Today we at last report news for which many of you waited long ago: beta testing of new service has ended, and we bring it into commercial operation. In this article we will in detail tell about options of use of new cloud, and also about its use will be paid for what rates.

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