Dobrev.EU Blog

Things I want to share

Running Docker With Open vSwitch Network Overlay on CentOS 7

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Docker containers are the technology of the decade that really sped-up CI/CD cycle. Running clustered Docker solutions sometimes require network fencing or multi-node connectivity. Lucky Docker supports Open vSwitch overlay networking out of the box with just few modifications to start-up services that I’m about to cover in this post.

New Server Host and IPv6

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Over a month ago I moved away from my virtual dedicated server hosting to a physical dedicated server and I can now run IPv6 on top of existing IPv4 stack. Plenty of options arise from this change, for example I can offer small isolated LXD like containers with unique IPv6 addresses.

The Foreman - the Scalable Way - Part 3

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I already explained how to put Foreman and Puppet server behind a load-balancer. It’s time to scale up and add additional Foreman/Puppet master nodes. This setup doesn’t really differ from creating your first backend. There is just one really important thing that needs your attention.

The Foreman - the Scalable Way - Part 2

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In part 1 of this article I’ve discussed the setup of Puppet CA server and the initial setup of a load-balancer node that routes traffic to backend(s). The config in question so far is related to Puppet 3 infrastructure. What I decided to do (or better admit forced to do) meanwhile is an upgrade of my existing infrastructure to Puppet 4. Without getting into all the details about changes in API calls between versions etc. here’s what I had to do/change in order to make it all tick like a Swiss clock ;). Goal is to have a running Puppet 4 infrastructure that’s compatible with Puppet 3 agents too.

Creating an Elastic Cloud for Running Containers Using Apache Mesos, Marathon, Chronos and Consul

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Docker containers became very popular in the past decade. A lot of companies created numerous products for Container orchestration – Kubernetes, Docker Swarm and Apache Mesos are worth mentioning as they have the biggest share of customers running containers in their production stack. I’m planning to cover the installation and configuration of Apache Mesos, Marathon, Chronos, Consul, mesos-consul and consul-template.

Strenghten SSL Configuration - POODLE & Heartbleed Mitigation

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Ever since Edward Snowden revealed some of the secrets of NSA a lot of websites are looking into options to secure their traffic. Using SSL for HTTPS/TLS connections is one of the mostly used techniques. But using the right settings is mostly important. Most modern webservers come with all cipher suites enabled, fine tuning is necessary in this case.

Create GSM Gateway Using Banana Pi With Asterisk 11

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A while back I stumbled upon an article describing a way to use 3G mobile dongle and Raspberry Pi with PBX software to create a GSM VoIP gateway. Another user managed to use similar setup to make calls between Germany and Cambodia and avoid ridiculous roaming charges while abroad. So looking at success stories I came up with an idea to implement something similar for my personal use and provide means for my family abroad to call me any time without being charged for international calls. This article is describing all required steps to create your own VoIP gateway.