Docker: change default IP address ranges

In this tutorial, I will explain how to change Docker’s default address range. By default, Docker uses class “B” private addresses from 172.17 to 172.32. For each “stack” or container, it will assign a range with a mask in /16. Here is an example : In some cases, it may be necessary to modify this …

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Proxmox: create a private network with NAT

In this tutorial, I will explain to you how to create a private network on Proxmox and configure NAT so that the LXC/CT containers and virtual computers in this network have access to the Internet. Using NAT in this situation will bring out the VM and CT to the Internet with the IP address of …

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GLPI 10: network inventory with GLPI Agent

In this tutorial, I will explain to you how to set up network inventory in GLPI 10 with GLPI Agent. This is the functionality equivalent to network discovery and inventory with FusionInventory: Fusion Inventory: Configuring Discovery and Inventory Tasks – 247-IT Presentation of network inventory with GLPI Agent The network inventory allows you to discover …

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GPO: force DNS computer registration

In this tutorial, I will explain how to force DNS registration of computers by Group Policy (GPO) in an Active Directory environment. Maintaining a clean, up-to-date DNS (Active Directory) zone is not easy, especially with dynamic computer registration. The first step is the activation of automatic cleaning, but it happens that once this is activated, …

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Crowdsec: secure your web server network – installation and configuration

In this tutorial, I will explain to you how to secure the network part of your web servers with Crowdsec. The tutorial is made on Ubuntu 20.04 Crowdsec overview Crowdsec is an open source tool that allows you to “secure” or rather add a layer of security to your Linux servers (soon Windows too) by …

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Use the hosts file to simulate a DNS record on Windows

Location of the hosts file : C:\Windows\System32\drivers\etc. Pour ajouter un enregistrement : 1. Start notepad as administrator. 2. Open the hosts file located in C:\Windows\System32\drivers\etc. To display the hosts file which has no extension it is necessary to select All files (*. *) 3. Add a record in the form: 4. Save and close the …

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Hyper-V : create a NAT switch

Microsoft Hyper-v

In this tutorial, I will explain how to create a NAT switch (virtual switch) on Hyper-V. Before getting into the technical explanations, I will explain in a few words, what a NAT switch is. If you have already used another hypervisor such as vmware or virtualbox for example, this type of switch is available by …

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