Cisco
How to Copy a Cisco IOS Image Between Routers Using TFTP
Copy a Cisco IOS image from one router to another with the built-in TFTP server. Step-by-step commands, MD5 verification and tips for replacements.
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Cisco
How to Replace a Faulty Cisco Router: Step-by-Step Guide
Replace a faulty Cisco ISR or ASR router with minimal downtime: back up the config, transfer the IOS image over TFTP, migrate licenses and verify.
Cisco
Convert Cisco Switch from Install Mode to Bundle Mode
Convert Cisco Catalyst switches from install mode back to bundle mode. Covers prerequisites, IOS-XE commands, verification, troubleshooting and rollback.
Cisco
How to Replace a Faulty Cisco Switch in a StackWise Stack
Replace a failed Cisco StackWise switch with minimal downtime. Covers prerequisites, removing and rejoining stack members, verification and best practices.
Check Point
How to Change DNS Settings in Check Point Firewall (Clish)
Change the DNS servers on a Check Point firewall using Clish, verify DNS traffic with tcpdump and fix an old DNS server by restarting the WSDNSD service.
Cisco
How to Configure Local Users on Cisco Devices
Create local user accounts on Cisco routers and switches. Learn privilege levels, secret vs password types and role-based access with clear CLI examples.
Check Point
How to Reset SIC in Check Point Firewall
Reset SIC (Secure Internal Communication) between a Check Point gateway and management server to fix trust errors such as SIC not initialized.
Cisco
What Is an SVI? SVI vs VLAN Explained with Examples
Learn what a Switched Virtual Interface (SVI) is, how it works on Layer 3 switches and how it differs from a VLAN, with inter-VLAN routing examples.
Cisco
How to Extend a Cisco Console Cable Using Cat6
Extend a Cisco console connection over Cat6 cabling using a patch panel, an RJ45-to-DB9 adapter or a direct run. Compare methods and fix common problems.
Cisco
Cisco DHCP Snooping Configuration Guide with Examples
Configure DHCP Snooping on Cisco switches to block rogue DHCP servers and DHCP-based attacks. Includes examples, verification commands and troubleshooting.
Cisco
How to Upgrade Cisco Catalyst 2960 Switch IOS (TFTP and USB)
Upgrade the IOS on a Cisco Catalyst 2960 switch step by step. Covers backup, TFTP and USB methods, image verification, boot settings and troubleshooting.
Check Point
How to Create Domain Objects in Check Point (FQDN Guide)
Create and use Domain Objects in Check Point firewalls. Learn FQDN vs non-FQDN objects, the steps in SmartConsole, best practices and known limitations.
Basic Networking
DNS Record Types Explained: A, MX, TXT, CNAME and More
Understand common DNS record types (A, AAAA, NS, MX, TXT, CNAME, SOA, PTR, SRV, CAA), what each does, its security impact and how to manage DNS safely.
Basic Networking
Email Header Analyzer: Trace Origin and Check SPF, DKIM, DMARC
Analyze email headers online to trace the sender and mail servers, check SPF, DKIM and DMARC results, find delays and spot phishing or spoofing.
Cisco
Cisco VXLAN: Architecture, Configuration and Troubleshooting
Learn how Cisco VXLAN works, its architecture and use cases, then configure it with multicast or BGP EVPN, integrate with vPC and troubleshoot problems.
Cisco
Cisco Catalyst Switch QoS Configuration Guide
Configure QoS on Cisco Catalyst switches: classification, queuing and scheduling, voice VLAN integration and best practices to prioritize critical traffic.
Cisco
Cisco Router and Switch Password Recovery Procedures
Recover a lost password on Cisco routers, Catalyst and Nexus switches and restore a corrupted IOS using ROMMON, with step-by-step procedures per platform.
Cisco
Cisco Switch Hardening Best Practices and Configuration
Harden Cisco IOS switches against common threats: secure management access, disable unused services, enable port security and protect STP, with commands.
Cisco
How to Configure VRRP on Cisco Routers and Switches
Configure VRRP on Cisco devices with step-by-step examples, load-balancing groups, verification commands, failover testing and troubleshooting tips.
Cisco
HSRP vs VRRP vs GLBP: Gateway Redundancy Configuration
Compare HSRP, VRRP and GLBP gateway redundancy protocols with Cisco configuration examples, failover behavior, verification commands and troubleshooting.
Cisco
What Is NAT? Types, Configuration and Examples on Cisco
Learn what NAT is and how it works, then configure static NAT, dynamic NAT, PAT and port forwarding on Cisco devices with verification and troubleshooting.
Windows
Windows Networking Commands: Troubleshooting and Admin Guide
Essential Windows networking commands such as ipconfig, ping, tracert, pathping, nslookup and netstat, with examples for troubleshooting and administration.
Check Point
Check Point Firewall Troubleshooting and Debug Commands
Troubleshoot Check Point firewalls with fw monitor, tcpdump, zdebug, fw ctl and cpstat. Commands for VPN, NAT, routing and traffic flow analysis.
Cisco
How to Configure AAA on Cisco: Local, TACACS+ and RADIUS
Configure AAA (authentication, authorization and accounting) on Cisco devices using local users, TACACS+ or RADIUS, with examples, best practices and fixes.
Cisco
Upgrade Cisco Catalyst 9300 in Bundle Mode: Step-by-Step
Upgrade a Cisco Catalyst 9300 running in bundle mode: pre-checks, backup, image transfer, MD5 check, boot config, verification, rollback and install mode.
Cisco
Upgrade Cisco Catalyst 9300 in Install Mode: Step-by-Step
Upgrade a Cisco Catalyst 9300 in IOS-XE install mode: pre-checks, backup, flash cleanup, image transfer, MD5 check, install, verification and rollback.
Cisco
Cisco Nexus vPC Explained: Architecture and Configuration
Understand Cisco Nexus vPC: key components, architecture and design, basic configuration, and verification and monitoring for high availability.
Cisco
How to Upgrade Cisco Firepower Management Center (FMC)
Upgrade Cisco FMC using the GUI or CLI: prerequisites, uploading the upgrade file, readiness checks, monitoring progress and post-upgrade verification.
Cisco
Cisco Error-Disabled Mode: Causes and How to Fix It
Find and fix Cisco switch ports in error-disabled state. Learn the common causes, how to identify ports, run TDR and duplex checks and recover the port.
Cisco
How to Test LAN Cables on Cisco Switches Using TDR
Use the built-in Time-Domain Reflectometer (TDR) on Cisco switches to test Ethernet cables, read the results and find shorts, opens and faulty cabling.
Cisco
How to Upgrade Cisco Catalyst 4500 Switch Software
Upgrade a Cisco Catalyst 4500 switch: preparation, image copy to bootflash, boot settings, post-upgrade verification, rollback and best practices.
Cisco
How to Upgrade Cisco Catalyst 9200 in Install Mode
Upgrade a Cisco Catalyst 9200 in IOS-XE install mode: pre-checks, backup, flash cleanup, image transfer, MD5 check, install, verification and rollback.
Cisco
Convert Cisco Catalyst 9200 from Bundle to Install Mode
Convert a Cisco Catalyst 9200 from bundle mode to install mode following Cisco best practice: prerequisites, commands, verification, rollback and cleanup.
Cisco
How to Upgrade Cisco Catalyst 3850 in Install Mode
Upgrade a Cisco Catalyst 3850 in IOS-XE install mode: pre-upgrade checks, backup, flash cleanup, image transfer, MD5 verification, install and cleanup.
Cisco
How to Recover a Cisco Device Stuck in ROMMON Using TFTP
Recover a Cisco router or switch stuck in ROMMON mode: download the IOS from a TFTP server, set the boot variables correctly and boot normally again.
Cisco
How to Upgrade or Downgrade NX-OS on Cisco Nexus Switches
Upgrade or downgrade NX-OS on Cisco Nexus switches safely: prerequisites, ISSU considerations, step-by-step procedure, verification and rollback tips.
Cisco
How to Configure vPC on Cisco Nexus Switches
Configure vPC (Virtual Port-Channel) on Cisco Nexus: peer link, keep-alive, member ports, downstream switch setup and verification for redundancy.
Network Automation
Python Script to Run Commands on Multiple Cisco Devices
Use a Python Paramiko script to run predefined CLI commands on multiple Cisco switches, check reachability and save the output to organized log files.
Windows
Fix Virtualized VT-x/EPT Not Supported Error on Windows 11
Fix the VT-x/EPT is not supported on this platform error on Windows 11 with five solutions for VMware, Hyper-V and VirtualBox nested virtualization.
Windows
How to Move the Default User Profile Folder to Another Drive
Move new Windows user profiles to another drive by editing the registry and creating new accounts, with an optional .reg script. Ideal when C: is low on space.
Windows
VMware Network Types Explained: Bridged, NAT, Host-Only
Compare VMware virtual network types: Bridged, NAT, Host-Only, LAN Segment and No Network, with use cases, configuration details and a comparison chart.
Windows
How to Fix Slow VMware Performance on Windows 11
Fix slow VMware performance on Windows 11 by disabling Hyper-V, turning off Memory Integrity and tuning VMware settings for better speed and stability.
Cisco
Step-by-Step OSPF Configuration on Cisco Routers
Configure OSPF on Cisco routers step by step: interface setup, OSPF process configuration, neighbor verification and connectivity testing in a simple lab.
Cisco
HSRPv2 Configuration on Cisco Switches for Multiple VLANs
Configure HSRP version 2 on Cisco switches for multiple VLANs to keep the default gateway highly available, with SW1 and SW2 configs and verification.
Cisco
HSRPv1 Configuration on Cisco Switches for Multiple VLANs
Configure HSRP version 1 across multiple VLANs on Cisco switches for a highly available default gateway, with SW1 and SW2 configs and verification.
Check Point
100 Check Point Firewall Questions and Answers
100 essential Check Point firewall questions and answers for interviews and exams, covering VPN, NAT, stateful inspection, ClusterXL and Identity Awareness.
Windows
Fix Slow Hyper-V Guest Network on Dell PowerEdge Servers
Fix slow network performance for Hyper-V guest VMs on Dell PowerEdge servers by configuring VMQ and the related registry settings, with verification steps.
Cisco
How to Set Up Cisco Router and Switch for Internet Access
Configure a Cisco router and switch to give LAN devices internet access: WAN and LAN setup, default route, DHCP and connectivity testing, step by step.
Cisco
How to Access Cisco Devices Through the Console Port
Connect to a Cisco switch or router through the console port: required cables, PuTTY serial settings, finding the COM port and step-by-step connection.
Basic Networking
How to Use iPerf for Bandwidth Testing on Windows
Use iPerf on Windows to test network bandwidth and connection speed and to troubleshoot network performance issues with simple client and server commands.
Cisco
Back Up and Restore Cisco Configuration Using TFTP
Back up and restore Cisco router and switch configurations over TFTP: SolarWinds TFTP server setup, copy commands, examples and best practices.
Fortinet
How to Configure FortiGate High Availability (HA)
Configure FortiGate HA in Active-Passive or Active-Active mode: prerequisites, device setup, failover testing and best practices for network resilience.
Check Point
Check Point Firewall Packet Flow Explained
Follow a packet through a Check Point firewall: SAM checks, anti-spoofing, NAT, VPN processing and deep packet inspection, explained step by step.
Cisco
How to Set Up Telnet on Cisco IOS Devices
Enable Telnet access on Cisco IOS devices: configure VTY lines, passwords and authentication. Includes a note on why SSH is the safer choice.
Cisco
How to Set Up SSH on Cisco IOS Devices (Secure Access)
Configure SSH on Cisco IOS devices: hostname, RSA key generation, VTY lines and best practices for secure remote access, plus SSH troubleshooting.
Network Automation
Extract Cisco Switch Serial Numbers with Python and Paramiko
Automate Cisco switch serial number collection with Python, Paramiko and Excel to build a network inventory, with the full script and how it works.
Network Automation
Save Switch Command Output to .txt with Python and Paramiko
Automate network switch configuration with Python and Paramiko: run commands on multiple devices and save the output to .txt files, with the script explained.
Network Automation
Automate Cisco Switch Health Checks with Python
Automate Cisco switch health checks with Python, Paramiko and OpenPyXL: monitor fan status, CPU and memory and generate an Excel health report.
Windows
Windows Commands to Check System Information and Health
Windows CMD and PowerShell commands to check system information, CPU, RAM, disk health, battery, BIOS, GPU and drivers for diagnostics and troubleshooting.
Windows
How to Activate Windows Behind a Proxy Server
Activate Windows in a proxy environment: set the WinHTTP proxy, verify the settings, enter the product key and reset the proxy after activation.
Windows
How to Edit the Hosts File on Windows (Step-by-Step)
Edit the Windows hosts file: open Notepad as administrator, add host entries, save, flush the DNS cache and fix common problems.
Basic Networking
How to Send a Test Email Using Telnet and EHLO
Send a test email manually with the SMTP EHLO command over Telnet. Full session walkthrough, real commands, common reply codes and troubleshooting.
Windows
How to Set a Proxy Server in Windows (4 Methods)
Set a proxy server in Windows using Settings, the registry, a batch script or browser settings. Step-by-step methods for privacy, security and performance.
Cisco
Cisco Switch Stacking: Benefits and Best Practices
Learn what Cisco switch stacking is, its benefits, how to connect switches in a stack and best practices for setup, management and scalability.
Check Point
Check Point tcpdump Commands for Firewall Troubleshooting
Capture and troubleshoot traffic on Check Point firewalls with tcpdump: filters for hosts, services and protocols, with ready-to-use command examples.
Cisco
How to Configure Syslog on Cisco Devices
Configure syslog on Cisco routers and switches: server setup, severity levels, timestamps and SNMP traps for monitoring, troubleshooting and security.
Cisco
How to Configure SNMPv3 on Cisco Devices (Secure Setup)
Configure SNMPv3 on Cisco devices with authentication and encryption. Includes an example config, best practices and troubleshooting for secure management.
Cisco
Inter-VLAN Routing on Cisco: Router and Layer 3 Switch
Configure inter-VLAN routing on Cisco routers and Layer 3 switches, learn when to use it and its benefits, and troubleshoot connectivity between VLANs.
Check Point
How to Export a Check Point Rulebase Policy to HTML
Export a Check Point firewall rulebase to HTML using expert mode commands, including the permissions change and verification for full IP and NAT visibility.
Windows
Fix CredSSP Encryption Oracle Remediation Error in RDP
Fix the CredSSP encryption oracle remediation error in Remote Desktop by temporarily changing a registry setting to reach servers that are not fully patched.
Cisco
How to Use Cisco Discovery Protocol (CDP)
Enable and use Cisco Discovery Protocol (CDP) to discover connected Cisco devices, view the network topology and gather device details for troubleshooting.
Check Point
Check Point Firewall Architecture: Components and Design
Understand Check Point firewall architecture: the three-tier model, management server, security gateway, inspection engine, communication and high availability.
Cisco
How to Configure Port Security on Cisco Switches
Configure port security on Cisco switches to limit devices per port, block unauthorized access and prevent MAC spoofing. Includes verification and removal.
Cisco
Configure a Cisco Router for Internet Access with VLANs
Configure a Cisco router and Layer 2 switch for internet access with WAN and LAN setup, default routes and VLANs, then verify with ping and traceroute.
Basic Networking
Ethernet Cable Categories Explained: Cat5e to Cat8
Compare Ethernet cable categories from Cat5e to Cat8: speeds, bandwidth and best use cases, to choose the right cable for your home or office network.
HPE
How to Enable Traceroute on HPE Routers and Switches
Enable traceroute on HPE routers and switches by turning on IP unreachables and TTL-expired replies, then save the configuration and troubleshoot connectivity.
Fortinet
How to Configure Custom NTP Servers on FortiGate
Set up custom NTP servers on FortiGate using the GUI or CLI. Covers why to use internal time servers, sync interval, verification commands and common fixes.
Check Point
Extend the /var/log Partition on Check Point with lvm_manager
Extend the /var/log partition on a Check Point firewall using lvm_manager: LVM overview, resizing steps, reboot impact and post-extension verification.
Basic Networking
Continuous Ping with Date and Time Stamps (Save to File)
Run a continuous ping that adds the date and time to every reply and saves the output to a text file. Ideal for catching intermittent drops and latency spikes.
Check Point
How to Enable Command History in Check Point Gaia
Enable command history on Check Point Gaia by editing /etc/bashrc and setting HISTFILESIZE in expert mode, then verify it works with practical examples.
Check Point
Check Point Policy Backup Using Migrate Export and Import
Back up and move a Check Point management server with migrate export and import: benefits, step-by-step commands, a worked example and best practices.
Cisco
How to Upgrade IOS on a Cisco 3850 Stack (TFTP or USB)
Upgrade a Cisco 3850 switch stack from IOS 16.03.03 to 16.06.08 using TFTP or USB, with an action plan, a rollback plan and best practices.
Cisco
Speed Up Cisco TFTP Transfers by Increasing Block Size
Speed up TFTP file transfers on Cisco devices with the ip tftp blocksize command: how block size works, the trade-offs and how to find the best value.
Cisco
Cisco IP SLA Configuration for Proactive Network Monitoring
Configure and use Cisco IP SLA to monitor latency, jitter, packet loss and uptime proactively and spot network problems before users notice them.
Cisco
Cisco DHCP Server Configuration and IP Reservation
Configure a DHCP server on a Cisco switch or router: exclude addresses, set the lease time and reserve fixed IPs with client-identifier, plus verification.
Cisco
How to Reset a Cisco Switch to Factory Defaults
Reset a Cisco switch to factory defaults using console commands or the Mode button, with step-by-step instructions and precautions for a safe reset.
Cisco
Recover Cisco Switch IOS Using XMODEM: Step-by-Step
Recover a corrupted Cisco switch IOS using XMODEM over the console: initialize flash, transfer the image and boot the new IOS, step by step.
Check Point
Migrate Check Point Management Server from R80.20 to R81.10
Migrate a Check Point management server from R80.20 to R81.10 with migrate_server export and import: planning, steps, SmartConsole setup and verification.
Basic Networking
How to Verify a File Hash (MD5, SHA) in Windows
Verify MD5 and SHA file hashes in Windows using Command Prompt, PowerShell or our hash calculator tool to confirm file integrity and security.
Cisco
Upgrade Cisco L2 Switch IOS Using TFTP with MD5 Check
Upgrade the IOS on a Cisco 2960 Layer 2 switch over TFTP: prerequisites, commands, MD5 verification and setting the new boot image, step by step.
Fortinet
How to Upgrade FortiGate Firewall Firmware (Step-by-Step)
Upgrade FortiGate firewall firmware to the latest FortiOS version: preparation, upgrade process, post-upgrade checks and rollback considerations.
Check Point
Fix: Unable to Connect to Check Point Management Server
Fix Check Point SmartConsole connection failures: check CPM process errors, CPU utilization and log files to restore access to the management server.
Cisco
EtherChannel Configuration on Cisco: LACP, PAgP and Static
Configure EtherChannel on Cisco switches with LACP, PAgP or static mode: prerequisites, step-by-step examples, verification, load balancing and troubleshooting.
Basic Networking
Ethernet Cable Color Coding: T568A, T568B and Crimping
Ethernet wiring standards T568A and T568B, straight-through vs crossover cables, RJ45 color codes, crimping steps and keystone jack punching, with diagrams.
Windows
How to Save PuTTY Output Automatically on Windows
Automatically save PuTTY session output to a log file on Windows using the built-in logging options, to keep commands and results for troubleshooting.
Network Automation
Automate Cisco Switch Configuration and Backup with Python
Automate Cisco switch configuration with Python and Paramiko: connect to devices, run commands and back up configs, with the full script explained.
Network Automation
Network Automation with Python: Fundamentals for Beginners
Learn network automation fundamentals with Python: key libraries like Netmiko and Paramiko, and how to build your first script to configure devices.
Network Automation
How to Install Python on Windows for Network Automation
Install Python 3.9.6 on Windows for network automation, step by step with screenshots, and verify the installation. Beginner friendly.
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