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1. What is the primary purpose of port aggregation in networking?
   a. Increase bandwidth and enhance redundancy by combining multiple physical ports into one logical link
   b. Reduce packet size for faster transmission
   c. Provide encryption for sensitive data transfer
   d. Assign separate VLANs to each port
   Answer: a. Increase bandwidth and enhance redundancy by combining multiple physical ports into one logical linkgeeksforgeeks+2
2. Which IEEE standard defines Link Aggregation Control Protocol (LACP)?
   a. IEEE 802.11ac
   b. IEEE 802.1Q
   c. IEEE 802.3ad
   d. IEEE 802.1X
   Answer: c. IEEE 802.3adcisco+2
3. What is the maximum number of active links allowed in a single LACP aggregation group?
   a. 4
   b. 8
   c. 16
   d. 2
   Answer: b. 8geeksforgeeks
4. Which of the following network layers does link aggregation typically operate on?
   a. Application
   b. Physical and Data Link
   c. Presentation
   d. Transport
   Answer: b. Physical and Data Linkgeeksforgeeks
5. Which two LACP modes are defined for port aggregation?
   a. Manual and Automatic
   b. Static and Dynamic
   c. Active and Passive
   d. Client and Server
   Answer: c. Active and Passivecisco+1
6. In LACP, what happens if both sides of the link are set to passive mode?
   a. Aggregation is still formed
   b. Aggregation fails to form
   c. Only one port becomes active
   d. Loop protection is enabled
   Answer: b. Aggregation fails to formcisco+1
7. Which type of port aggregation requires manual configuration without protocol negotiation?
   a. Static Link Aggregation
   b. LACP
   c. PAGP
   d. VLAN Trunking
   Answer: a. Static Link Aggregationgeeksforgeeks+1
8. Which of the following is a benefit of using port aggregation?
   a. Increases single-port performance above physical limits
   b. Provides bandwidth scalability and fault tolerance
   c. Adds more VLANs to a network
   d. Encrypts network traffic by default
   Answer: b. Provides bandwidth scalability and fault tolerancecbtnuggets+2
9. What does LACP use to exchange aggregation information between devices?
   a. ICMP packets
   b. LACPDUs
   c. TCP segments
   d. ARP requests
   Answer: b. LACPDUsarubanetworking.hpe+1
10. Which must match for Ethernet ports to be aggregated together?
    a. Duplex and speed settings
    b. IP addresses
    c. MAC addresses
    d. VLAN IDs
    Answer: a. Duplex and speed settingsibm+1
11. What is the default LACP system priority value on most switches?
    a. 32768
    b. 65535
    c. 1
    d. 100
    Answer: a. 32768cisco
12. What are ports put into if the aggregation group has reached its maximum number of active members?
    a. Forwarding state
    b. Blocking state
    c. Standby/unselected state
    d. Trunking state
    Answer: c. Standby/unselected stateh3c+1
13. Which of the following is NOT a troubleshooting step for port aggregation issues?
    a. Check physical connections
    b. Verify identical configurations on both ends
    c. Reboot network
    d. Check for hardware compatibility
    Answer: c. Reboot networkh3c+2
14. Which Cisco term is synonymous with port aggregation?
    a. EtherChannel
    b. FastChannel
    c. PortGuard
    d. TrunkLink
    Answer: a. EtherChannelitexamanswers+1
15. What determines whether an LACP port will be selected for aggregation in a group?
    a. Port ID and priority
    b. IP address only
    c. VLAN number
    d. Source MAC address only
    Answer: a. Port ID and priorityarubanetworking.hpe+1
16. What key benefit does link aggregation provide during device or link failure?
    a. Full redundancy/failover
    b. Automatic encryption
    c. Multicast filtering
    d. NAT translation
    Answer: a. Full redundancy/failoverwikipedia+1
17. What must be configured identically on all ports in a port aggregation group?
    a. Duplex, speed, VLAN, and allowed protocols
    b. Only IP address
    c. OSPF priority
    d. SNMP community
    Answer: a. Duplex, speed, VLAN, and allowed protocolscbtnuggets+2
18. On what basis does LACP assign port priority for link selection?
    a. Lowest MAC address
    b. Highest VLAN ID
    c. Administrator configuration or default value
    d. Packet length
    Answer: c. Administrator configuration or default valuearubanetworking.hpe+1
19. Which hashing method might be used in load balancing for link aggregation?
    a. Source and destination MAC or IP addresses
    b. Packet length only
    c. CRC32 checksum
    d. Device hostname
    Answer: a. Source and destination MAC or IP addresseswikipedia+1
20. If link aggregation is set up but traffic is not evenly balanced, what is likely the cause?
    a. Hashing algorithm not appropriate for the traffic pattern
    b. Wrong MAC address
    c. Excess VLANs
    d. Trunk port misconfiguration
    Answer: a. Hashing algorithm not appropriate for the traffic patternwikipedia+1
21. How many standby ports are allowed in an LACP group, given the maximum active ports are configured?
    a. Only one
    b. As many as eight (inactive)
    c. Equal to the number of VLANs
    d. Unlimited
    Answer: b. As many as eight (inactive)geeksforgeeks
22. Which of the following is NOT a limitation of link aggregation?
    a. Ports must have compatible settings
    b. Only increases throughput between the same two endpoints
    c. Cannot span multiple switches in any implementation
    d. May cause out-of-order packet delivery in some scenarios
    Answer: c. Cannot span multiple switches in any implementationwikipedia+1
23. Which port aggregation protocol is Cisco proprietary?
    a. PAgP
    b. LACP
    c. Static Link Aggregation
    d. MSTP
    Answer: a. PAgPcisco+1
24. What happens if a port in an aggregation group fails?
    a. Traffic is blackholed
    b. Remaining ports continue passing traffic with reduced bandwidth
    c. Entire aggregation stops working
    d. LACP disables spanning tree
    Answer: b. Remaining ports continue passing traffic with reduced bandwidthwikipedia+1
25. What does LACP use to identify aggregation groups between switches?
    a. System ID
    b. IP addressing
    c. Hostname
    d. EtherType field
    Answer: a. System IDarubanetworking.hpe+1
26. Which of the following statements about static link aggregation is true?
    a. It requires both ends to be configured identically and does not support negotiation
    b. It automatically negotiates with LACP-enabled neighbors
    c. It uses PoE by default
    d. It supports dynamic VLAN assignment
    Answer: a. It requires both ends to be configured identically and does not support negotiationgeeksforgeeks+1
27. What is the typical result if VLAN configuration differs on the two ends of a port channel?
    a. Port channel fails to form or drops some traffic
    b. Ports will aggregate anyway without loss
    c. No impact at all
    d. Ports reset to default VLAN
    Answer: a. Port channel fails to form or drops some trafficcbtnuggets+1
28. Which command might you use on an H3C device to view the aggregation port status?
    a. display link-aggregation verbose
    b. show port summary
    c. show vlan
    d. display snmp status
    Answer: a. display link-aggregation verboseh3c
29. What field in the LACPDU conveys information about a port’s role and status?
    a. System MAC
    b. Port number
    c. Operational key
    d. VLAN ID
    Answer: c. Operational keyarubanetworking.hpe
30. Which scenario would make LACP aggregation impossible?
    a. Mixed speeds among grouped ports
    b. All ports on same VLAN
    c. Identical port speeds and duplex
    d. LACP active mode on both ends
    Answer: a. Mixed speeds among grouped portsibm+1
31. How does link aggregation improve network availability?
    a. By allowing multiple links to share load and backup each other
    b. By encrypting traffic
    c. By using spanning tree as default
    d. By increasing routing protocol timers
    Answer: a. By allowing multiple links to share load and backup each otherwikipedia+1
32. Which of the following is NOT a required setting for the interfaces in an aggregation group?
    a. Matching speed and duplex
    b. Matching VLAN membership
    c. Matching IP address
    d. Matching trunking protocol
    Answer: c. Matching IP addressibm+2
33. In LACP, which mode will only respond to LACP packets but not initiate them?
    a. Active
    b. Standby
    c. Passive
    d. Monitor
    Answer: c. Passivecisco+1
34. Which aggregation method can dynamically detect link failures and reroute traffic seamlessly?
    a. LACP
    b. Static
    c. VLAN trunking
    d. Classic spanning tree
    Answer: a. LACPgeeksforgeeks+1
35. What is a risk when aggregating links across two switches, but only one switch supports link aggregation?
    a. The aggregation will only work on compatible devices
    b. The network forms a loop
    c. The link will be encrypted by default
    d. Packets are droppped by both devices
    Answer: a. The aggregation will only work on compatible deviceswikipedia+1
36. What is one advantage of deploying LACP over static aggregation?
    a. Automatic detection and removal of failed links
    b. Better encryption support
    c. Higher single-link speed
    d. No configuration required at all
    Answer: a. Automatic detection and removal of failed linkscisco+1
37. Which parameter determines the master device for LACP negotiation?
    a. System priority and MAC address
    b. Port description
    c. VLAN ID
    d. IP subnet
    Answer: a. System priority and MAC addressarubanetworking.hpe+1
38. Why must both ends of an aggregation group use the same protocol?
    a. To ensure both sides can negotiate and manage the group correctly
    b. For encryption to work
    c. Due to spanning tree requirements
    d. Because TCP is required
    Answer: a. To ensure both sides can negotiate and manage the group correctlygeeksforgeeks+1
39. Which port states are possible in LACP configuration on a switch?
    a. Selected, unselected, individual
    b. Forwarding, learning, listening
    c. Disabled, blocking, trunking
    d. Root, designated, backup
    Answer: a. Selected, unselected, individualh3c+1
40. If an aggregation group includes a port with mismatched VLAN settings, what should you do?
    a. Ensure all ports are on the same VLAN and reconfigure as needed
    b. Remove the aggregation and reboot
    c. Change the port’s MAC address
    d. Enable trunk-mode globally
    Answer: a. Ensure all ports are on the same VLAN and reconfigure as neededcbtnuggets+1
41. In link aggregation, which traffic balancing technique is commonly used?
    a. Per flow (based on hashing packet headers)
    b. Round robin for every packet
    c. Random selection
    d. Serial scheduling
    Answer: a. Per flow (based on hashing packet headers)wikipedia+1
42. What is a typical reason for a port to show “unselected” in a port aggregation status display?
    a. Too many active ports are already selected
    b. Trunking mismatch
    c. The port has the highest VLAN ID
    d. SNMP is disabled
    Answer: a. Too many active ports are already selectedh3c+1
43. What can be a symptom of a misconfigured port aggregation group?
    a. One-sided or asymmetric traffic flow
    b. Increased signal strength
    c. Decreased MTU size
    d. ARP table overflow
    Answer: a. One-sided or asymmetric traffic flowcbtnuggets+1
44. What initial troubleshooting step should be taken when aggregation links are not up?
    a. Verify physical layer connectivity of all connected ports
    b. Start debugging OSPF
    c. Change all MAC addresses
    d. Enable SNMP traps
    Answer: a. Verify physical layer connectivity of all connected portsh3c+1
45. What best describes LACP’s operation in “active” mode?
    a. The port actively initiates negotiation using LACP packets
    b. The port passively waits for negotiation
    c. The port is disabled
    d. The port blocks spanning tree BPDUs
    Answer: a. The port actively initiates negotiation using LACP packetscisco+1
46. Which Cisco command is used to create a static EtherChannel?
    a. channel-group <number> mode on
    b. lacp enable
    c. port-channel static
    d. vlan trunk add
    Answer: a. channel-group <number> mode onitexamanswers+1
47. What is the effect of enabling LACP on both ends of a link in “active” mode?
    a. Aggregation group automatically forms
    b. No aggregation happens
    c. Ports are disabled
    d. Port speed drops to 10 Mbps
    Answer: a. Aggregation group automatically formsgeeksforgeeks+1
48. Which failure scenario does LACP mitigate better than static aggregation?
    a. Unplanned physical link loss
    b. Spanning tree recalculation
    c. OSPF neighbor loss
    d. UDP packet loss
    Answer: a. Unplanned physical link losswikipedia+1
49. What is required for multi-chassis link aggregation (MC-LAG)?
    a. All member switches must support MC-LAG and have correct peer configuration
    b. Different system IDs at both ends
    c. Enabling spanning tree only
    d. Using portfast on all ports
    Answer: a. All member switches must support MC-LAG and have correct peer configurationwikipedia
50. Which LACP parameter can be tuned to prefer certain ports for selection when forming an aggregation group?
    a. Port priority
    b. VLAN ID
    c. SNMP index
    d. Routing metric
    Answer: a. Port priorityarubanetworking.hpe+1

1. https://www.geeksforgeeks.org/computer-networks/link-aggregation-control-protocol/
2. https://www.cbtnuggets.com/blog/technology/networking/what-is-port-aggregation
3. https://en.wikipedia.org/wiki/Link_aggregation
4. https://www.cisco.com/c/en/us/td/docs/ios/12_2sb/feature/guide/gigeth.html
5. https://arubanetworking.hpe.com/techdocs/AOS-CX/10.10/HTML/link_aggregation/Content/Chp_LAG/lac.htm
6. https://www.ibm.com/docs/en/aix/7.2.0?topic=configuration-ieee-8023ad-link-aggregation-troubleshooting
7. https://www.h3c.com/en/d_202505/2485319_294551_0.htm
8. https://itexamanswers.net/6-4-4-module-quiz-etherchannel-answers.html
9. https://wayground.com/admin/quiz/608525dfb18be7001bfd7536/link-aggregation
10. https://testbook.com/objective-questions/mcq-on-two-port-networks–5eea6a0e39140f30f369e561
11. https://www.sanfoundry.com/computer-network-questions-answers/
12. https://www.scribd.com/document/561210064/MIS-6314-Short-Quiz-3
13. https://testbook.com/objective-questions/mcq-on-interconnection-two-port-networks–5eea6a0e39140f30f369e567
14. https://www.interviewbit.com/computer-network-mcq/
15. https://www.uninets.com/blog/computer-networks-mcq
16. https://www.cisco.com/c/en/us/support/docs/lan-switching/link-aggregation-control-protocol-lacp-8023ad/221051-troubleshoot-link-aggregation-control-pr.html
17. https://www.scribd.com/document/455187372/MCQ-question-Latest
18. https://support.hpe.com/hpesc/public/docDisplay?docId=c03754914&docLocale=en_US
19. https://www.geeksforgeeks.org/quizzes/50-computer-networks-mcqs-with-answers/
20. https://www.ibm.com/docs/en/aix/7.1.0?topic=aggregation-ieee-8023ad-link-configuration