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25 Router Configuration and Mini Hack Completion

Warning

⚠️ 💥 ⚠️ NOTE: You will not be using a CentOS router in the 2025 NCAE challenge!!!⚠️ 💥 ⚠️

⚠️ 💥 ⚠At this point it is recommended you skip this video and do the current year's Mini Hack before continuing with the rest of the playlist!!!⚠️ 💥 ⚠

⭐ Mini Hack 2025: 44 MicroTik Routers and Mini Hack 2025 ⭐

  • Configuring the Router in Mini Hack
    • The router is set up using CentOS with two network interfaces.
    • Interfaces: eth0 for the external network (172.20.x.x) and eth1 for the internal network (192.168.x.x).
    • Initial setup involves configuring IP addresses but does not include routing yet.
  • Understanding Firewall Zones in CentOS
    • Firewall zones determine network access rules.
    • firewall-cmd --list-all-zones shows available zones like public, external, and internal.
    • By default, interfaces (eth0 and eth1) are assigned to the public zone.
  • Checking and Changing Firewall Zones
    • The firewall zones govern network permissions for each interface.
    • The external zone is preferred for eth0, while the internal zone is for eth1.
    • Changing zones is done via: firewall-cmd --change-interface=eth0 --zone=external --permanent.
  • Restarting and Verifying Firewall Settings
    • Changes to the firewall require a reload using firewall-cmd --reload.
    • firewall-cmd --list-all --zone=external verifies interface assignment and enabled services.
  • Enabling Masquerading for Routing
    • Masquerading allows internal devices to use the router for external access.
    • The external zone has masquerading enabled by default, reducing manual setup.
    • This enables internal machines to communicate with external networks via the router.
  • Configuring Port Forwarding for Web Traffic
    • External web requests to port 80 must be forwarded to the internal web server.
    • The command for forwarding:
      firewall-cmd --zone=external --add-forward-port=port=80:proto=tcp:toport=80:toaddr=192.168.x.x --permanent
    • A firewall reload is required to apply the change.
  • Ensuring Gateway Configuration for Internal Devices
    • Internal devices must have the router’s internal IP (192.168.x.1) set as their default gateway.
    • In Ubuntu, Netplan configuration is updated with gateway4: 192.168.x.1.
    • Restarting networking services applies the gateway settings.
  • Testing Network and Web Access
    • ping tests internal devices' connectivity to the router and external network.
    • curl or a browser verifies if external traffic reaches the internal web server.
    • The scoreboard system confirms if the router and web services are properly configured.
  • Finalizing Mini Hack Setup
    • A fully functional router allows internal devices to access external networks.
    • Port forwarding ensures external web access is properly redirected.
    • Understanding firewall zones, masquerading, and gateways is key to successful routing.

Next in Playlist: 26 Mini Hack Reconfiguration