Practice Test GeeksLinux Practice Test
← All Linux Flashcard Decks

Linux+ Networking Services and Protocols Flashcards

7 cards from real Linux practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Linux+ Networking Services and Protocols flashcards as text

  1. Which command generates an SSH key pair on a Linux system?

    Answer: ssh-keygen

    ssh-keygen creates RSA, ECDSA, or Ed25519 key pairs used for SSH public-key authentication.

  2. Which file on an SSH server is the primary configuration file for the SSH daemon?

    Answer: /etc/ssh/sshd_config

    /etc/ssh/sshd_config is the main configuration file for the SSH daemon (sshd) and controls server-side behavior.

  3. Which DNS record type maps a hostname to an IPv4 address?

    Answer: A

    An A record maps a hostname to an IPv4 address; AAAA records are used for IPv6 addresses.

  4. Which command provides the most detailed DNS query output, including response time and authoritative server information?

    Answer: dig

    dig (Domain Information Groper) provides verbose DNS query output including query time, server used, and full answer sections.

  5. What TCP port does SSH use by default?

    Answer: 22

    SSH uses TCP port 22 by default for establishing encrypted remote connections.

  6. What is the purpose of the /etc/resolv.conf file?

    Answer: Define DNS nameserver addresses and search domains

    /etc/resolv.conf specifies the DNS nameserver addresses and search domains the system uses for hostname resolution.

  7. Which command copies a local SSH public key to a remote server's authorized_keys file?

    Answer: ssh-copy-id user@host

    ssh-copy-id appends the local public key to the remote server's ~/.ssh/authorized_keys, enabling key-based authentication.