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SSL connection from GNS3 Docker through a corporate security

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 Corporate security has become very restrictive. A joke is that even Pearson VUE connection test is failing from my corp laptop. One of the recent issue I had when started Practical Python Cisco Network Automation chapter from INE CCNP learning path. The built in Docker network automation container in GNS3 wasn't connecting, returning "failed to verify certificate: x509: certificate: certificate signed by unknown authority."  in the logs. First help came from here  https://forums.docker.com/t/tls-failed-to-verify-certificate-x509/137486  with two commands checking connection and showing certificate chain.  curl -vvvv https://registry-1.docker.io openssl s_client -showcerts -connect registry- 1 .docker.io: 443 </dev/null | more Those clearly indicated that there is a issue with certificate and there is something in the chain shouldn't be there: Cloud Services Root CA by a BlueCoat Systems. The solution came from here:  https://johnpfield.wordpress...
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EDU-JUN-JMV lab on vMX. Part1.

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This time I'm going to continue my experiments with Juniper virtualMX I've started in this getting started post   It was written in Russian, but contains enough pictures and CLI issues which describe themselves. Now I'll cover how to set up Junos MPLS and VPN's labs with vMX. That may be useful for companies with a low education budget as a way to spread knowledge among staff. Objective I intend to solve two main tasks. Firstly, I have to deploy an appropriate topology in a virtual environment and accomplish two basic labs: Lab-1 and Lab-6 so as to prepare baseline configurations used in the rest of labs. Secondly, I must see that it works :) thus I will perform Lab-12 LDP based VPLS - my beloved technology. Physical topology. Almost physical) Let's take a diagram from site provides Juniper labs for rent  and make something similar. It will take two vMX - vr1 and vr2 for the core network and a couple vMX as two PE routers called mx...
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Cisco Policing and Shaping.

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Общая идея механизмов известна: установить контрактную скорость, считать пакеты, при превышении скорости полисер дропает лишние пакеты а шейпер копит в буфере.  Немного терминов. CIR – committed information rate. Контрактная скорость. Не надо забывать, что механизмы не от хорошей жизни. Их назначение в том, что при покупке полосы у провайдера вы должны отправлять пакеты максимум на этой полосе. Иначе они будут справедливо дропаться.  PIR – peak information rate. Переподписка! Провайдер вам продал полосу, но готов пропускать больше трафика (пока суммарно канал не загружен). Вероятность дропа как бы выше, для этого пакеты с рейтом выше CIR но ниже PIR часто помечают худшим маркером. Tc – time interval (measurement interval) . Фактически это время усреднения, интервал на котором будет отправлено пакетов столько, чтоб не превысить CIR. Bc – committed burst. Пакеты отправляются на физической скорости интерфейса. Так как за время Tc мы должны получить сре...
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