AboutNet · all about networks

AboutNet all about networks

Understanding and Deploying Cisco SD-WAN (BRKRST-2767)

Device roles

  • vManage - interface for login to the system, configure, monitor and troubleshoot it;
  • vSmart Controllers - brains of the operation. Policies configured on vManage pushed down to vSmart Controllers;
  • vBond - tool for ZTP, it instruct routers how to join the network;
  • On-Site routers (vEdge or Cisco ASR/ISR 1k/4k in 2018).


Overlay Management Protocol (OMP) - TCP based control protocol, creates a peering relationships between vEdge routers and vSmart Controllers over the TLS/DTLS tunnels and used to exchange policies and routes.

At the same time BFD used to provide health checks of the network (DSCP CS6 now and different DSCP values to simulate specific protocols in future implementations).

Transport Locators (TLOCs) - identifiers of vEdge routers and vSmart Controllers.

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NetBox and Oxidized integration

In our company we use NetBox to manage devices information, such as IP addresses, serial numbers, etc., Oxidized/GitLab to store device configuration files, Zabbix to monitor everything and Confluence for any other documentation.

Earlier, when we connected a new device to the network, we needed to manually add it at least to the listed systems.

Fortunately, NetBox has an excellent API (this was one of the criteria by which I chose him), that allows us to automate some routine.

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RHCE System Optimization Basics



procfsis a virtual filesystem, usually mounted on/proc. Contains generic kernel parameters.

mount | grep proc
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)

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Сборка deb пакета из программы на Python

Дано - примитивный демон на python, который:

  1. Слушает 80 порт;
  2. Возвращает строку “It Works”;
  3. Читает из конфигурационного файла расположение log файла;
  4. Пишет в указанный log файл о соединении;
  5. Закрывает соединение.

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SQL Basics


Конспект курса Learn SQL с ресурса codeacademy.com. Во всех примерах используется синтаксис SQLite.

Реляционные базы данных - базы данных, организованные в виде одной или нескольких таблиц. Таблица - определенный набор данных. Таблицы состоят из строк и столбцов (полей и записей).

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