UNIX Question and Answer – Network Services
UNIX MCQ – Multiple Choice Questions for exam, interview, and Entrance Test
1. What does LDAP stand for in UNIX network services?
a) Lightweight Directory Access Protocol
b) Local Directory Access Protocol
c) Legacy Directory Access Protocol
d) Long Directory Access Protocol
Answer: a) Lightweight Directory Access Protocol
Explanation: LDAP is used for accessing and managing directory information over a network.
2. Which port number is commonly used by LDAP?
a) 389
b) 443
c) 80
d) 25
Answer: a) 389
Explanation: Port 389 is typically used by LDAP for communication.
3. Which command is used to query an LDAP directory in UNIX?
a) ldapquery
b) ldapsearch
c) ldappoll
d) ldapfind
Answer: b) ldapsearch
Explanation: The ldapsearch command is used to query an LDAP directory in UNIX.
4. What does DNS stand for in UNIX network services?
a) Domain Name Service
b) Domain Network Service
c) Distributed Name Service
d) Distributed Network Service
Answer: a) Domain Name Service
Explanation: DNS is used to translate domain names into IP addresses and vice versa.
5. Which port number is commonly used by DNS?
a) 53
b) 25
c) 110
d) 80
Answer: a) 53
Explanation: Port 53 is used by DNS for communication between clients and servers.
6. Which command is used to perform DNS lookups in UNIX?
a) nslookup
b) dig
c) host
d) dnsquery
Answer: a) nslookup
Explanation: The nslookup command is used to perform DNS lookups in UNIX.
7. What does DHCP stand for in UNIX network services?
a) Dynamic Host Configuration Protocol
b) Domain Host Configuration Protocol
c) Distributed Host Configuration Protocol
d) Dynamic Host Control Protocol
Answer: a) Dynamic Host Configuration Protocol
Explanation: DHCP is used to dynamically assign IP addresses and other network configuration parameters to devices on a network.
8. Which port number is commonly used by DHCP?
a) 67
b) 53
c) 68
d) 161
Answer: a) 67
Explanation: Port 67 is used by DHCP servers for sending DHCP messages.
9. Which command is used to configure a DHCP client on a UNIX system?
a) dhclient
b) dhcpconfig
c) dhcpcd
d) dhcpclient
Answer: a) dhclient
Explanation: The dhclient command is used to configure a DHCP client on a UNIX system.
10. What is the primary purpose of the dhcpd daemon in UNIX?
a) Assign IP addresses to DHCP clients
b) Configure DHCP client settings
c) Manage DNS records
d) Monitor network traffic
Answer: a) Assign IP addresses to DHCP clients
Explanation: The dhcpd daemon is responsible for assigning IP addresses to DHCP clients in UNIX.
11. Which protocol is commonly used for securely transferring files between systems in UNIX?
a) FTP
b) TFTP
c) FTPS
d) SFTP
Answer: d) SFTP
Explanation: SFTP (SSH File Transfer Protocol) provides secure file transfer capabilities over an encrypted SSH connection in UNIX.
12. Which command is used to initiate an SFTP session in UNIX?
a) sftp
b) ftp
c) scp
d) ssh
Answer: a) sftp
Explanation: The sftp command is used to initiate an SFTP session for secure file transfer in UNIX.
13. Which port number is commonly used by SFTP for communication?
a) 20
b) 21
c) 22
d) 23
Answer: c) 22
Explanation: Port 22 is commonly used by SFTP for secure communication.
14. What is the primary advantage of SFTP over traditional FTP?
a) Simplicity
b) Speed
c) Security
d) Compatibility
Answer: c) Security
Explanation: SFTP provides encryption and secure authentication, making it more secure compared to traditional FTP.
15. Which command is used to transfer files between UNIX systems over SSH?
a) ftp
b) scp
c) sftp
d) rsync
Answer: b) scp
Explanation: The scp command is used for secure copy between UNIX systems over an SSH connection.
16. Which protocol is commonly used for secure remote access to graphical desktop environments in UNIX?
a) RDP
b) SSH
c) VNC
d) Telnet
Answer: c) VNC
Explanation: VNC (Virtual Network Computing) provides secure remote access to graphical desktop environments in UNIX.
17. Which command is used to initiate a VNC session in UNIX?
a) vncserver
b) vncviewer
c) vnccreate
d) vncconnect
Answer: b) vncviewer
Explanation: The vncviewer command is used to initiate a VNC session in UNIX.
18. Which port number is commonly used by VNC for communication?
a) 20
b) 21
c) 22
d) 5900
Answer: d) 5900
Explanation: Port 5900 is commonly used by VNC for communication.
19. What is the primary purpose of the rsync command in UNIX?
a) Synchronize files and directories
b) Remote shell access
c) Secure file transfer
d) Network diagnostics
Answer: a) Synchronize files and directories
Explanation: The rsync command is used to synchronize files and directories between systems in UNIX.
20. Which command is used to synchronize files from a local directory to a remote directory over SSH using rsync?
a) rsync -r local_directory remote_user@remote_host:remote_directory
b) rsync -a remote_user@remote_host:remote_directory local_directory
c) rsync -l local_directory remote_user@remote_host:remote_directory
d) rsync -s remote_user@remote_host:remote_directory local_directory
Answer: a) rsync -r local_directory remote_user@remote_host:remote_directory
Explanation: The -r option is used to recursively synchronize files from a local directory to a remote directory over SSH using rsync.
21. Which protocol is commonly used for remote access to serial ports in UNIX?
a) Telnet
b) SSH
c) Serial-over-IP
d) Telnet-over-serial
Answer: c) Serial-over-IP
Explanation: Serial-over-IP allows remote access to serial ports over a network in UNIX.
22. Which command is used to initiate a serial-over-IP session in UNIX?
a) socat
b) ser2net
c) telnet
d) ssh
Answer: b) ser2net
Explanation: The ser2net command is used to initiate a serial-over-IP session in UNIX.
23. Which port number is commonly used by serial-over-IP for communication?
a) 20
b) 21
c) 23
d) 2000
Answer: d) 2000
Explanation: Port 2000 is commonly used by serial-over-IP for communication.
24. Which protocol is commonly used for remote access to desktop environments in UNIX?
a) RDP
b) SSH
c) VNC
d) Telnet
Answer: c) VNC
Explanation: VNC (Virtual Network Computing) is commonly used for remote access to desktop environments in UNIX.
25. Which command is used to initiate an RDP session in UNIX?
a) rdesktop
b) xrdp
c) vncviewer
d) rdpconnect
Answer: a) rdesktop
Explanation: The rdesktop command is used to initiate an RDP session in UNIX.
26. Which protocol is commonly used for remote access to Windows desktop environments from UNIX systems?
a) RDP
b) SSH
c) VNC
d) Telnet
Answer: a) RDP
Explanation: RDP (Remote Desktop Protocol) is commonly used for remote access to Windows desktop environments from UNIX systems.
27. Which command is used to initiate a telnet session in UNIX?
a) ssh
b) telnet
c) rlogin
d) nc
Answer: b) telnet
Explanation: The telnet command is used to initiate a telnet session in UNIX.
28. Which port number is commonly used by telnet for communication?
a) 20
b) 21
c) 22
d) 23
Answer: d) 23
Explanation: Port 23 is commonly used by telnet for communication.
29. What is the primary disadvantage of using telnet for remote access compared to SSH?
a) Lack of encryption
b) Slower connection speed
c) Limited compatibility
d) Higher resource usage
Answer: a) Lack of encryption
Explanation: Telnet transmits data in plain text, making it vulnerable to interception, unlike SSH, which provides encryption.
30. Which command is used to initiate a secure shell (SSH) session in UNIX?
a) ssh
b) scp
c) sftp
d) telnet
Answer: a) ssh
Explanation: The ssh command is used to initiate a secure shell (SSH) session in UNIX.
31. Which protocol is commonly used for securely accessing remote shell sessions in UNIX?
a) Telnet
b) SSH
c) FTP
d) RDP
Answer: b) SSH
Explanation: SSH (Secure Shell) provides encrypted remote shell access in UNIX environments, enhancing security compared to Telnet.
32. Which command is used to initiate an SSH session in UNIX?
a) ssh
b) scp
c) sftp
d) telnet
Answer: a) ssh
Explanation: The ssh command is used to initiate SSH sessions for remote shell access and secure file transfer.
33. Which port number is commonly used by SSH for communication?
a) 20
b) 21
c) 22
d) 23
Answer: c) 22
Explanation: Port 22 is the default port used by SSH for secure communication.
34. What is the primary advantage of using SSH over Telnet?
a) Faster connection speed
b) Greater compatibility
c) Encryption of data
d) Lower resource usage
Answer: c) Encryption of data
Explanation: SSH encrypts data transmitted over the network, providing enhanced security compared to Telnet.
35. Which command is used to transfer files securely between systems over SSH in UNIX?
a) ftp
b) scp
c) sftp
d) rsync
Answer: b) scp
Explanation: The scp command is used for secure file transfer between systems over SSH in UNIX.
36. Which command is used to configure the SSH server settings in UNIX?
a) sshdconfig
b) sshd_conf
c) sshconfig
d) sshd
Answer: d) sshd
Explanation: The sshd command is used to configure the SSH server settings in UNIX.
37. What does RDP stand for in UNIX network services?
a) Remote Desktop Protocol
b) Remote Data Protocol
c) Remote Directory Protocol
d) Remote Deployment Protocol
Answer: a) Remote Desktop Protocol
Explanation: RDP is a protocol used for remote access to graphical desktop environments.
38. Which command is used to initiate an RDP session in UNIX?
a) rdp
b) xrdp
c) vncviewer
d) rdesktop
Answer: d) rdesktop
Explanation: The rdesktop command is used to initiate an RDP session in UNIX.
39. Which port number is commonly used by RDP for communication?
a) 3389
b) 22
c) 5900
d) 23
Answer: a) 3389
Explanation: Port 3389 is commonly used by RDP for communication.
40. Which protocol is commonly used for remote access to Windows desktop environments from UNIX systems?
a) RDP
b) SSH
c) VNC
d) Telnet
Answer: a) RDP
Explanation: RDP (Remote Desktop Protocol) is commonly used for remote access to Windows desktop environments from UNIX systems.
41. Which command is used to initiate a Telnet session in UNIX?
a) ssh
b) telnet
c) rlogin
d) nc
Answer: b) telnet
Explanation: The telnet command is used to initiate a Telnet session in UNIX.
42. Which port number is commonly used by Telnet for communication?
a) 20
b) 21
c) 22
d) 23
Answer: d) 23
Explanation: Port 23 is commonly used by Telnet for communication.
43. What is the primary disadvantage of using Telnet for remote access compared to SSH?
a) Lack of encryption
b) Slower connection speed
c) Limited compatibility
d) Higher resource usage
Answer: a) Lack of encryption
Explanation: Telnet transmits data in plain text, making it vulnerable to interception, unlike SSH, which provides encryption.
44. Which command is used to check the status of SSH connections in UNIX?
a) sshd_status
b) ssh_status
c) sshd -status
d) systemctl status sshd
Answer: d) systemctl status sshd
Explanation: The systemctl command is used to check the status of SSH connections in UNIX.
45. Which protocol is commonly used for remote access to graphical desktop environments in UNIX?
a) SSH
b) RDP
c) VNC
d) Telnet
Answer: c) VNC
Explanation: VNC (Virtual Network Computing) is commonly used for remote access to graphical desktop environments in UNIX.
46. Which command is used to initiate a VNC session in UNIX?
a) vnc
b) vncviewer
c) vncserver
d) vncconnect
Answer: b) vncviewer
Explanation: The vncviewer command is used to initiate a VNC session in UNIX.
47. Which port number is commonly used by VNC for communication?
a) 20
b) 21
c) 22
d) 5900
Answer: d) 5900
Explanation: Port 5900 is commonly used by VNC for communication.
48. What is the primary purpose of the rsync command in UNIX?
a) Synchronize files and directories
b) Remote shell access
c) Secure file transfer
d) Network diagnostics
Answer: a) Synchronize files and directories
Explanation: The rsync command is used to synchronize files and directories between systems in UNIX.
49. Which command is used to synchronize files from a local directory to a remote directory over SSH using rsync?
a) rsync -r local_directory remote_user@remote_host:remote_directory
b) rsync -a remote_user@remote_host:remote_directory local_directory
c) rsync -l local_directory remote_user@remote_host:remote_directory
d) rsync -s remote_user@remote_host:remote_directory local_directory
Answer: a) rsync -r local_directory remote_user@remote_host:remote_directory
Explanation: The -r option is used to recursively synchronize files from a local directory to a remote directory over SSH using rsync.
50. Which protocol is commonly used for remote access to serial ports in UNIX?
a) Telnet
b) SSH
c) Serial-over-IP
d) Telnet-over-serial
Answer: c) Serial-over-IP
Explanation: Serial-over-IP allows remote access to serial ports over a network in UNIX.