As hosts come online and go offline, there is a constant churn of hosts communicating on a local area...
Tag Archive for: networking
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Cisco CUCM (CallManager) architecture

One of the most popular Voice Over IP systems is the Cisco Unified Communication Manager System. Cisco uses several...
How to install the PfSense firewall on a virtual machine

PfSense is a free open-source network firewall and router based on FreeBSD. PfSense is known for its reliability and...
Free network speed test tools

Running a simple network speed test is often a good start when troubleshooting or verifying network performance. Such a...
Install Windows Fax Server in Windows Server 2022

Windows Fax Server has been around for quite some time and is still part of Windows Server 2022. So...
Activate DNS over TLS (DoT) in Windows 11

The current Insider preview in the Dev Channel includes support for DNS over TLS (DoT). This is an alternative...
Netsh winsock reset

If the internet is not working on a Windows PC where everything related to networking is properly configured, the...
Network management software from Auvik: Cloud-based and easy to use

Auvik is cloud-based, easy-to-use network monitoring and management software that provides true visibility, control, and key insights into your...
Cisco config backup with Python

In a previous article, we looked at how to leverage the Python Module Paramiko to connect to Cisco routers...
Install ESXi network drivers for Intel e1000 and Intel I220 / I221 / I225/ I226 chipsets

Many IT professionals and others run VMware lab environments for learning, certification prep, evaluation, and other use cases. They...
Python module Paramiko for managing CISCO devices: Installation and usage example

The Python module Paramiko enables you to leverage Python to automate the management of CISCO routers and switches. In...
SMB port number: Ports 445, 139, 138, and 137 explained

The SMB port number is TCP 445. If you've heard people saying the port number is 139, they could...
The SMB protocol: All you need to know

The SMB protocol is a client–server communication protocol that has been used by Windows since the beginning for sharing...
Set up a VPN server on Windows with SoftEther and connect clients

SoftEther VPN is an open-source VPN solution that offers a wide range of authentication and connectivity options for multiple...
Configuring DFS Namespaces for Amazon FSx for Windows file servers

This step-by-step guide explains how to configure DFS Namespaces for Amazon FSx for Windows file servers.
Capture outbound connections initiated on your host with tcpdump and WinDump on Linux and Windows

If your server initiates connections to an unknown host, it might be a sign that your server has been...
3CX communications system: Phone system for Windows, Linux, and the cloud

The 3CX communications system is an open-platform phone system that runs on-premises with Windows or Linux and in the...
Secure DNS requests over HTTPS (DoH) in Windows 10/11

DNS over HTTPS (DoH) is a security feature that safeguards the authenticity of DNS servers and hides requests from...
VMware vSphere 7 Networking Policies configuration

VMware vSphere 7 has networking policies that can be applied to both vSphere Standard Switch (VSS) and vSphere Distributed...
Hybrid DNS between AWS and on-prem with AWS Route 53 Resolver

This step-by-step guide explains how to create a hybrid DNS solution between AWS and an on-prem network using AWS...