Network

Study the scheme. Split the network into subnets, addressing 5.87.0.0/24. Each PC is on a separate network. Perform basic configuration of all network devices. Raise only SSH protocol for management. Configure a separate VLAN for each PC on the switches and forward them to the router. Enable Port Fast BPDU Guard on internal interfaces. Enable Rapid PVST. Configure the OSPF protocol for routers, not including networks on internal interfaces. Raise a floating static route for OSPF protocol redundancy....

Cisco allows you to perform laboratory work or test the APIs in sandbox. It is completely free. All the necessary devices are available in the sandbox permanently or by reservation. Here’s what Cisco writes about it: DevNet Sandbox makes Cisco’s free spread of technology available to developers and engineers by providing packaged labs we call Sandboxes. That’s right, totally free! There are two types of sandboxes, Always-On and Reservation. Each sandbox typically highlight one Cisco product (think, CallManager, APIC, etc)....

В прошлой статье я рассказал как подготовить и запустить любую версию виртуального маршрутизатора Cisco - Cloud Services Router (СSR1000v) в VirtualBox под Windows. С версии Cisco IOS XE 3.13S можно обойтись без настройки последовательного интерфейса. Запускать будем всё тот же релиз 3.15.0S. С официального сайта нужно скачать файлы csr1000v-universalk9.03.15.00.S.155-2.S-std.iso и csr1000v-universalk9.03.15.00.S.155-2.S-std.ova По-моему, сейчас это самая поздняя версия CSR, доступная с аккаунтом Cisco, версии новее требуют различные партнерские отношения с Cisco. Зарегистрироваться можно по адресу....

Я расскажу как подготовить и запустить виртуальный маршрутизатор Cisco - Cloud Services Router (СSR1000v) в VirtualBox под Windows с эмуляцией serial port, настроить доступ по telnet, ssh и написать скрипт на python для автоматизации конфигурирования. Необходимый софт С официального сайта нужно скачать файлы csr1000v-universalk9.03.15.00.S.155-2.S-std.iso и csr1000v-universalk9.03.15.00.S.155-2.S-std.ova. По-моему, сейчас это самая поздняя версия CSR, доступная с аккаунтом Cisco, версии новее требуют различные партнерские отношения с Cisco. Зарегистрироваться можно по адресу. Если еще не установлен VirtualBox, скачайте и установите....

In Yandex.Cloud, you can deploy a Cisco Cloud Services Router (CSR) 1000v virtual router from a ready-made virtual machine image. There is an awesome manual at this link to Yandex docs. For my experiments, I ran two instances of CSR1000v. I have configured a connection to one of them using SSH. Both of them are interconnected by a local network. This is one of the possible ways to study the training courses of the Cisco Network Academy....

A tunnel is organized between the two branches via the ISP. For redundancy, a second tunnel is organized over the network of another ISP. Scheme with IP-addresses: Switching to the backup route is performed when OSPF connectivity is lost through the tunnel over the network of the ISP “A”. BFD is used to quickly evaluate connectivity. The settings for routers: Router WEST hostname WEST no ip domain lookup interface Loopback0 no shutdown description PC_A ip address 172....

I got acquainted with the emulated vitrual environment EVE-NG. The image with EVE for VMware (OVF version) and all the necessary utilities can be downloaded from the official website eve-ng.net. Images of devices are easy to find with Google or on the official websites of manufacturers. For example, for mikrotik. You can add your own images in this way (for example, Cisco router and switch images and the windows client side for EVE-NG):...

Starting from IOS 15.1 cisco command history is appeared. It outputs a pretty nice ASCII diagram of interfaces loading. For enable: (config)# interface GigabitEthernet 0/1 (config-if)# history bps Now you can see the result using the command: # show interface GigabitEthernet 0/1 history 60sec input The different periods (60sec, 60min, 72hour) and different traffic directions (input, output, both) are available.

Do you need to mix traffic between different VLANs without any limits and configuration settings? The best way is to inject a hub between access ports on switch and customers. This is actually a joke. But, unfortunately, this is possible, and there is no way to hope for the STP. The first thing that should alert you is the repeated messages "%CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on…" if CDP is enabled....

For some pet projects, I need multiple instances of different servers. The best way is to use Docker. And the best way to automate configuration services that run in docker containers is Ansible. This is the sequence of steps to run Ansible to configure containerized services in Ubuntu. Installing Docker Engine on Ubuntu is very well described on the official website. A summary of the steps: sudo apt-get update sudo apt-get install apt-transport-https ca-certificates curl gnupg-agent software-properties-common curl -fsSL https://download....