Networking Flashcards
7 cards from real Linux practice questions. Tap to flip, then mark Knew It or Still Learning โ missed cards come back until you master them.
Read the first 7 Networking flashcards as text
What does CIDR notation `/24` indicate about a network?
Answer: The first 24 bits are the network portion
In CIDR notation, `/24` means 24 bits are used for the network prefix, leaving 8 bits for host addresses (254 usable hosts).
Which command would you use to test if a remote host is reachable at the network layer?
Answer: ping
`ping` sends ICMP echo request packets to test basic connectivity and measure round-trip time to a host.
What is the loopback IP address in IPv4?
Answer: 127.0.0.1
127.0.0.1 is the IPv4 loopback address (also `localhost`) used by the system to communicate with itself.
Which tool scans for open ports and services on a target host?
Answer: nmap
`nmap` (Network Mapper) is a widely-used tool for port scanning, service detection, and network discovery.
What does the ARP protocol resolve?
Answer: IP addresses to MAC addresses
ARP (Address Resolution Protocol) maps an IPv4 address to the corresponding hardware (MAC) address on a local network segment.
Which `netstat` flag shows only listening sockets?
Answer: -l
The `-l` flag in `netstat` (or `ss -l`) filters output to display only sockets in the listening state.
What is the default gateway's role in a network?
Answer: Routes traffic destined for networks outside the local subnet
The default gateway is the router that handles traffic destined for IP addresses not in the local subnet.