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What is the purpose of VLAN trunking in Cisco networking?
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What is the purpose of VLAN trunking in Cisco networking?
To divide a large network into smaller, manageable subnetworks
To provide access control for network resources
To carry traffic for multiple VLANs over a single link
To prioritize certain types of traffic over others
Correct answer
To carry traffic for multiple VLANs over a single link
Explanation: VLAN trunking in Cisco networking is used to carry traffic for multiple VLANs over a single link. It allows for the aggregation of traffic from multiple VLANs and facilitates communication between devices in different VLANs.
A network administrator notices that a Cisco Nexus switch port is in the errdisabled state due to a BPDU guard violation. What could be a possible cause of this issue?
Physical layer issues such as a cable disconnect or faulty port
Incorrect VLAN configuration on the switch port
Spanning Tree Protocol (STP) blocking the switch port due to a loop
Excessive broadcast traffic on the network
Correct answer
Spanning Tree Protocol (STP) blocking the switch port due to a loop
Explanation: A BPDU guard violation on a Cisco Nexus switch port indicates that the Spanning Tree Protocol (STP) has detected a loop in the network topology. This typically occurs when a switch port receives BPDUs (Bridge Protocol Data Units) from a non-STP device, leading to the port being disabled to prevent network loops.
What is a key benefit of server profiles in Cisco UCS Manager?
Increased network security through role-based access control
Simplified management of individual hardware components
Flexible and automated provisioning of server resources
Enhanced data protection through encryption
Correct answer
Flexible and automated provisioning of server resources
Explanation: Server profiles in Cisco UCS Manager provide a key benefit of flexible and automated provisioning of server resources. They allow administrators to define and enforce server configurations, policies, and connectivity requirements, enabling rapid deployment and scaling of server workloads.
A network administrator is unable to establish a Telnet connection to a Cisco Nexus switch. What could be a possible cause of this issue?
Misconfigured Telnet settings on the switch
Incompatible Telnet client software
Incorrect IP address configured on the switch
Faulty network cable connecting the switch to the network
Correct answer
Misconfigured Telnet settings on the switch
Explanation: A possible cause of being unable to establish a Telnet connection to a Cisco Nexus switch is misconfigured Telnet settings on the switch. This could include disabled Telnet access, incorrect Telnet port settings, or misconfigured authentication settings.
What is the purpose of the Cisco Nexus Virtual Device Context (VDC) feature in a data center environment?
To optimize power consumption by disabling unused VLANs
To provide secure access control to network resources
To logically partition a single physical switch into multiple virtual switches
To prioritize network traffic based on application requirements
Correct answer
To logically partition a single physical switch into multiple virtual switches
Explanation: The Cisco Nexus Virtual Device Context (VDC) feature allows for the logical partitioning of a single physical switch into multiple virtual switches. Each VDC operates as an independent switch with its own set of management, configuration, and resource allocation.
What is the purpose of ARP (Address Resolution Protocol) in TCP/IP networking?
To assign IP addresses dynamically to network devices
To provide access control for network resources
To resolve IP addresses to MAC addresses
To prioritize certain types of traffic over others
Correct answer
To resolve IP addresses to MAC addresses
Explanation: ARP (Address Resolution Protocol) is used to resolve IP addresses to MAC addresses in TCP/IP networking. When a device needs to communicate with another device on the same network, it uses ARP to discover the MAC address associated with the destination IP address.
Which Ethernet standard specifies 100 Gigabit Ethernet over fiber optic cabling?
IEEE 802.11
IEEE 802.3ae
IEEE 802.1Q
IEEE 802.3z
Correct answer
IEEE 802.3ae
Explanation: IEEE 802.3ae is the standard that specifies 100 Gigabit Ethernet over fiber optic cabling. It defines the physical layer characteristics and signaling for high-speed Ethernet transmission over fiber optic links.
A network administrator is experiencing intermittent connectivity issues with a Cisco Nexus switch. What should be checked first to troubleshoot this issue?
VLAN configurations on the switch
Physical layer connections and cables
Routing table entries on the switch
Trunking configurations on the switch
Correct answer
Physical layer connections and cables
Explanation: When troubleshooting intermittent connectivity issues, the physical layer connections and cables should be checked first to ensure that there are no issues with the physical connectivity between devices. This includes verifying cable connections, checking for link lights, and ensuring cable integrity.
What is the primary function of the Cisco Nexus Data Broker feature in a data center environment?
To optimize power consumption by disabling unused VLANs
To provide secure access control to network resources
To aggregate and distribute network traffic for monitoring and analysis
To prioritize network traffic based on application requirements
Correct answer
To aggregate and distribute network traffic for monitoring and analysis
Explanation: The Cisco Nexus Data Broker feature is designed to aggregate and distribute network traffic for monitoring and analysis purposes in a data center environment. It allows network administrators to efficiently capture, filter, and analyze traffic flows for troubleshooting and security monitoring.
Which Cisco product provides centralized storage networking services and supports Fibre Channel and FCoE (Fibre Channel over Ethernet) protocols?
Cisco Nexus 9000 Series
Cisco MDS 9000 Series
Cisco UCS Manager
Cisco HyperFlex
Correct answer
Cisco MDS 9000 Series
Explanation: The Cisco MDS 9000 Series provides centralized storage networking services and supports Fibre Channel and FCoE (Fibre Channel over Ethernet) protocols. It is designed for high-performance storage networking in data center environments.
What is the purpose of dynamic trunking protocol negotiation in Cisco networking?
To optimize power consumption by disabling unused VLANs
To provide access control for network resources
To negotiate trunking configurations dynamically between switches
To prioritize certain types of traffic over others
Correct answer
To negotiate trunking configurations dynamically between switches
Explanation: Dynamic trunking protocol negotiation in Cisco networking is used to negotiate trunking configurations dynamically between switches. It allows switches to automatically establish trunk links and negotiate trunking protocols such as ISL (Inter-Switch Link) or IEEE 802.1Q.
A network administrator notices high CPU utilization on a Cisco Nexus switch. What could be a possible cause of this issue?
Misconfigured VLAN settings on the switch
Excessive broadcast traffic on the network
Incorrect IP address configuration on the switch
Insufficient memory resources on the switch
Correct answer
Excessive broadcast traffic on the network
Explanation: High CPU utilization on a Cisco Nexus switch could be caused by excessive broadcast traffic on the network. This requires the CPU to process and forward packets, leading to increased CPU load. Identifying and mitigating sources of broadcast storms can help alleviate CPU utilization issues.
What is a key benefit of service profiles in Cisco UCS Manager?
Increased network security through role-based access control
Simplified management of individual hardware components
Flexible and automated provisioning of server resources
Enhanced data protection through encryption
Correct answer
Flexible and automated provisioning of server resources
Explanation: A key benefit of service profiles in Cisco UCS Manager is the flexible and automated provisioning of server resources. Service profiles abstract server configurations from physical hardware, allowing administrators to easily provision, modify, and migrate server workloads.
A network administrator is unable to establish an SSH connection to a Cisco Nexus switch. What could be a possible cause of this issue?
Misconfigured SSH settings on the switch
Incompatible SSH client software
Incorrect IP address configured on the switch
Faulty network cable connecting the switch to the network
Correct answer
Misconfigured SSH settings on the switch
Explanation: A possible cause of being unable to establish an SSH connection to a Cisco Nexus switch is misconfigured SSH settings on the switch. This could include disabled SSH access, incorrect SSH version settings, or misconfigured authentication settings.
What is the role of a MAC address in Ethernet networking?
To identify a device on a local network
To identify a device on the internet
To provide access control for network resources
To prioritize certain types of traffic over others
Correct answer
To identify a device on a local network
Explanation: MAC (Media Access Control) addresses are used to uniquely identify devices on a local network. They are assigned to network interface controllers for communication within the same network segment.
Which IEEE standard defines the specifications for Gigabit Ethernet over fiber optic cabling (1000BASE-SX and 1000BASE-LX)?
IEEE 802.11
IEEE 802.3ab
IEEE 802.3ae
IEEE 802.1Q
Correct answer
IEEE 802.3ae
Explanation: IEEE 802.3ae specifies the specifications for Gigabit Ethernet over fiber optic cabling, including 1000BASE-SX and 1000BASE-LX. It defines the physical layer characteristics and signaling for Gigabit Ethernet transmission over fiber optic links.
A network administrator is unable to access a Cisco Nexus switch remotely using SSH. What should be checked first to troubleshoot this issue?
IP address configuration on the switch
SSH client software compatibility
SSH access settings on the switch
Physical connectivity to the switch
Correct answer
SSH access settings on the switch
Explanation: When unable to access a Cisco Nexus switch remotely using SSH, the first step in troubleshooting should be to check the SSH access settings on the switch. This includes verifying that SSH access is enabled, correct authentication methods are configured, and any access control lists (ACLs) are allowing SSH traffic.
What is the primary purpose of VLANs (Virtual Local Area Networks) in Cisco networking?
To increase network speed
To improve network security
To provide access control for network resources
To logically segment a single physical network into multiple virtual networks
Correct answer
To logically segment a single physical network into multiple virtual networks
Explanation: The primary purpose of VLANs in Cisco networking is to logically segment a single physical network into multiple virtual networks. This allows for improved network efficiency, better resource utilization, and enhanced security by isolating traffic within each VLAN.
Which Cisco product provides virtualized networking services and supports features such as VXLAN (Virtual Extensible LAN) and ACI (Application Centric Infrastructure)?
Cisco Nexus 9000 Series
Cisco MDS 9000 Series
Cisco UCS Manager
Cisco HyperFlex
Correct answer
Cisco Nexus 9000 Series
Explanation: The Cisco Nexus 9000 Series provides virtualized networking services and supports features such as VXLAN (Virtual Extensible LAN) and ACI (Application Centric Infrastructure). It is designed for scalable and programmable data center networking.
What is the purpose of VLAN tagging in Ethernet networking?
To encrypt network traffic for security
To identify the source and destination MAC addresses
To prioritize certain types of traffic over others
To identify the VLAN membership of Ethernet frames
Correct answer
To identify the VLAN membership of Ethernet frames
Explanation: VLAN tagging is used to identify the VLAN membership of Ethernet frames as they traverse trunk links between network devices. It helps switches distinguish between different VLANs and forward traffic accordingly.
A network administrator is unable to establish a Telnet connection to a Cisco Nexus switch. What could be a possible cause of this issue?
Misconfigured Telnet settings on the switch
Incompatible Telnet client software
Incorrect IP address configured on the switch
Faulty network cable connecting the switch to the network
Correct answer
Misconfigured Telnet settings on the switch
Explanation: A possible cause of being unable to establish a Telnet connection to a Cisco Nexus switch is misconfigured Telnet settings on the switch. This could include disabled Telnet access, incorrect Telnet port settings, or misconfigured authentication settings.
What is a key benefit of service profiles in Cisco UCS Manager?
Increased network security through role-based access control
Simplified management of individual hardware components
Flexible and automated provisioning of server resources
Enhanced data protection through encryption
Correct answer
Flexible and automated provisioning of server resources
Explanation: A key benefit of service profiles in Cisco UCS Manager is the flexible and automated provisioning of server resources. Service profiles abstract server configurations from physical hardware, allowing administrators to easily provision, modify, and migrate server workloads.
A network administrator notices high CPU utilization on a Cisco Nexus switch. What could be a possible cause of this issue?
Misconfigured VLAN settings on the switch
Excessive broadcast traffic on the network
Incorrect IP address configuration on the switch
Insufficient memory resources on the switch
Correct answer
Excessive broadcast traffic on the network
Explanation: High CPU utilization on a Cisco Nexus switch could be caused by excessive broadcast traffic on the network. This requires the CPU to process and forward packets, leading to increased CPU load. Identifying and mitigating sources of broadcast storms can help alleviate CPU utilization issues.
What is the purpose of the Cisco Nexus Virtual Device Context (VDC) feature in a data center environment?
To optimize power consumption by disabling unused VLANs
To provide secure access control to network resources
To logically partition a single physical switch into multiple virtual switches
To prioritize network traffic based on application requirements
Correct answer
To logically partition a single physical switch into multiple virtual switches
Explanation: The Cisco Nexus Virtual Device Context (VDC) feature allows for the logical partitioning of a single physical switch into multiple virtual switches. Each VDC operates as an independent switch with its own set of management, configuration, and resource allocation.
Which layer of the OSI model is responsible for ensuring the reliable transmission of data over a network connection?
Network Layer (Layer 3)
Transport Layer (Layer 4)
Data Link Layer (Layer 2)
Session Layer (Layer 5)
Correct answer
Transport Layer (Layer 4)
Explanation: The Transport Layer (Layer 4) is responsible for ensuring reliable transmission of data over a network connection. It achieves this through mechanisms such as flow control, error detection, and error correction.
What is the purpose of the Cisco Nexus Fabric Extender (FEX) in a data center environment?
To provide server connectivity to the fabric without adding additional switch ports
To extend the reach of the fabric across multiple data centers
To optimize power consumption in the data center
To provide centralized management of network devices
Correct answer
To provide server connectivity to the fabric without adding additional switch ports
Explanation: The Cisco Nexus Fabric Extender (FEX) is designed to provide server connectivity to the fabric without adding additional switch ports. It extends the fabric to servers and simplifies management by allowing the fabric switches to manage the FEX-connected servers as if they were directly connected.
A network administrator is unable to ping a remote server from a Cisco Nexus switch. What could be a possible cause of this issue?
VLAN misconfiguration
Incorrect subnet mask configuration
Routing table misconfiguration
Physical layer issues
Correct answer
Routing table misconfiguration
Explanation: If the network administrator is unable to ping a remote server from a Cisco Nexus switch, a possible cause could be routing table misconfiguration. If the switch does not have the correct route to the remote server, it will be unable to forward the ICMP packets, resulting in ping failures.
What is the purpose of Cisco UCS (Unified Computing System)?
To provide virtualized compute, storage, and networking resources
To provide centralized management of network devices
To optimize power consumption in the data center
To extend the reach of the fabric across multiple data centers
Correct answer
To provide virtualized compute, storage, and networking resources
Explanation: Cisco UCS (Unified Computing System) is designed to provide virtualized compute, storage, and networking resources in a single integrated platform. It offers a unified architecture for managing and provisioning data center resources efficiently.
Which Cisco product is a software-defined networking (SDN) solution that provides centralized automation and policy-driven application profiles?
Cisco Nexus 9000 Series
Cisco MDS 9000 Series
Cisco UCS Manager
Cisco ACI (Application Centric Infrastructure)
Correct answer
Cisco ACI (Application Centric Infrastructure)
Explanation: Cisco ACI (Application Centric Infrastructure) is a software-defined networking (SDN) solution that provides centralized automation and policy-driven application profiles. It simplifies network provisioning and management while optimizing application performance.
A network administrator notices that a Cisco Nexus switch port is in the errdisabled state due to a BPDU guard violation. What could be a possible cause of this issue?
Physical layer issues
VLAN misconfiguration
Excessive broadcast traffic
Misconfigured switch port
Correct answer
Excessive broadcast traffic
Explanation: A BPDU guard violation on a Cisco Nexus switch port indicates that the Spanning Tree Protocol (STP) has detected excessive broadcast traffic, leading to a potential network loop. This can cause the port to enter the errdisabled state to prevent network instability.
Recall the answer before opening each card.
To carry traffic for multiple VLANs over a single link using tagging to identify VLAN membership.
Spanning Tree Protocol detects a loop when a port receives BPDUs from a non-STP device, disabling the port to prevent network loops.
Flexible and automated provisioning of server resources, allowing rapid deployment and migration by abstracting hardware configurations.
It logically partitions a single physical switch into multiple independent virtual switches with separate management and resources.
To resolve IP addresses to MAC addresses on a local network segment for frame delivery.
IEEE 802.3ae defines 100GbE over fiber optic cabling.
Check physical layer connections and cables for links, lights, and integrity.
To aggregate and distribute network traffic for monitoring and analysis.
Cisco MDS 9000 Series provides centralized storage networking services with Fibre Channel and FCoE.
It automatically negotiates trunking configurations between switches to establish trunk links using protocols like ISL or IEEE 802.1Q.
Excessive broadcast traffic on the network, requiring the CPU to process and forward many packets.
To uniquely identify a device on a local network segment for Layer 2 communication.
To identify the VLAN membership of Ethernet frames as they traverse trunk links between switches.
To provide server connectivity to the fabric without adding additional switch ports, simplifying cabling and management.
Routing table misconfiguration on the switch, lacking a correct route to the destination.
To provide virtualized compute, storage, and networking resources in a single integrated platform for efficient data center management.
Cisco ACI (Application Centric Infrastructure) offers centralized automation and policy-driven application profiles.
Misconfigured Telnet settings such as disabled service, incorrect port, or authentication misconfiguration.
100 Gigabit Ethernet over fiber optic cabling specifications.
The port is disabled to prevent network loops; it can be re-enabled with 'shutdown' and 'no shutdown' after resolving the cause.
Read the prompt, commit to an answer, then flip the card. Move through the deck at your own pace and repeat any topic that does not come back quickly.
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Connect the concepts
Open a branch to connect a topic with its practice questions and explanations. Use the map to choose your next review topic.
This is an analysis of the practice bank, not a claim about the vendor's live exam blueprint. Use it to identify the knowledge, judgment, and recall patterns exercised here, then verify your coverage against the current official exam guide.
VLANs logically segment a physical network into multiple virtual networks, improving efficiency and security. Trunking carries multiple VLANs over a single link using tagging (802.1Q or ISL). Dynamic trunking protocol negotiates trunking automatically. Ethernet standards like IEEE 802.3ae define 100 Gigabit Ethernet over fiber. Understanding these fundamentals is essential for configuring and troubleshooting data center switches.
Common switch issues include BPDU guard violations (due to STP loop or excessive broadcast), high CPU from broadcast storms, and errdisabled ports. Troubleshooting starts with physical layer checks, then verification of STP configuration, and remote access settings (SSH, Telnet). Misconfigured authentication, disabled services, or ACLs can block connections. Ping failures often result from routing misconfigurations.
The Cisco Nexus Virtual Device Context (VDC) partitions a physical switch into multiple virtual switches, each with independent management. Fabric Extender (FEX) provides server connectivity without additional switch ports, simplifying cabling. Data Broker aggregates and distributes network traffic for monitoring and analysis. These features enhance scalability and operational efficiency in data centers.
Cisco UCS integrates compute, storage, and networking with service profiles for automated provisioning. Server profiles abstract hardware configurations, enabling rapid deployment and migration. ACI provides policy-driven automation and application profiles for SDN. The MDS 9000 Series supports Fibre Channel and FCoE for storage networking. Understanding these platforms is critical for data center design and management.
Study workflow
When a Nexus switch port enters errdisabled due to BPDU guard, first verify that no unauthorized devices are sending BPDUs. Check if STP is properly configured. Re-enable the port with 'shutdown' followed by 'no shutdown'. If the issue recurs, examine the network topology for loops and ensure all ports are using portfast where appropriate.
To enable SSH, first generate RSA keys using 'crypto key generate rsa'. Set the SSH version with 'ip ssh version 2'. Configure authentication via local username/password or AAA. Finally, ensure the VTY lines allow SSH transport using 'line vty' and 'transport input ssh'. Test connectivity from a remote host.
On Cisco Nexus, use 'show interface trunk' to see trunk ports and allowed VLANs. To configure a trunk, set the interface to 'switchport mode trunk' and specify allowed VLANs. Ensure the native VLAN matches on both ends. For dynamic negotiation, use 'switchport mode dynamic desirable' or 'auto' as needed.
To create a VDC on a Nexus 7000 or 7700, use 'vdc <name>' in global config. Allocate resources like memory and interfaces with 'allocate'. Then enter the VDC context with 'switchto vdc <name>'. Each VDC has its own management IP, config, and run state, allowing administrative isolation.
In UCS Manager, navigate to Servers > Service Profiles > Create Service Profile. Assign a name, UUID, and LAN/SAN connectivity policies. Bind it to a service profile template for consistency. Then associate it with a physical blade by specifying a pool or selecting a specific server. The server will automatically boot with the defined configuration.
FAQ
Clear boundaries on what the bank covers, how to use it, and where official vendor information still matters.
VLAN trunking allows traffic from multiple VLANs to traverse a single link between switches. It uses tagging (IEEE 802.1Q or ISL) to identify each frame's VLAN, enabling efficient use of ports and simplifying network topology.
VDC (Virtual Device Context) logically partitions one physical Nexus switch into multiple independent virtual switches. Each VDC has its own configuration, protocols, and management, allowing for multi-tenant isolation and administrative separation without additional hardware.
The FEX extends the switch fabric to servers by acting as a remote line card. It provides server connectivity using simplified cabling and centralizes management. The parent switch manages all FEX-attached ports, reducing the need for standalone access switches.
Common causes include SSH not being enabled, incorrect RSA key generation, wrong SSH version, misconfigured VTY transport, ACL blocking SSH traffic, or authentication issues (local or AAA). Check 'show ssh' and 'ip ssh' details.
Cisco ACI (Application Centric Infrastructure) uses a policy-driven model where network policies are defined based on application requirements. It centralizes automation through the APIC controller, supports VXLAN overlays, and provides granular visibility and management compared to manual CLI-based configuration.
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