Instiq

2Networking Fundamentals

Practice questions →Glossary →
  • 2.1Internet Protocol Fundamentals

    Learn the foundations of TCP/IP: IP addresses, subnet masks and CIDR notation, private vs public IP addresses, the natures of TCP, UDP, and ICMP, well-known ports (22/25/53/80/123/443), and the differences between IPv4 and IPv6.

  • 2.2Basic Network Configuration

    Learn to view and change host network settings: the ip command (ip addr, ip route) and legacy ifconfig/route, interface up/down (ifup, ifdown), NetworkManager's nmcli, the hostname (/etc/hostname), basic resolution files (/etc/hosts, /etc/nsswitch.conf), the default route, and reachability checks with ping.

  • 2.3Basic Network Troubleshooting

    Learn to isolate network failures: reachability (ping, ping6), path tracing (traceroute, tracepath), name resolution checks (host, dig), port/connection inspection (ss, netstat, netcat), interface reconfiguration (ifconfig, ifup/ifdown, hostname), and fixing the routing table.

  • 2.4Client-Side DNS Configuration

    Learn the DNS client settings a host uses: specifying resolvers in /etc/resolv.conf (nameserver, search), querying remote DNS servers (host, dig), the relationship with /etc/hosts, testing with getent, and changing the order via /etc/nsswitch.conf.