350-601 Storage Network Practice Test 8 — 15 Questions

Question 1

A company is deploying a new SAN with two MDS 9148S switches in a single VSAN. They want to ensure that a failure of one switch does not affect storage traffic. Which technology should be implemented?

Accepted Answer

Create a redundant fabric by connecting both switches to each storage array and host via multiple paths.. Implementing a redundant fabric by connecting both switches to each storage array and host via multiple paths ensures that if one switch fails, the other switch continues to carry storage traffic. This is achieved through multipathing software (e.g., Fibre Channel multipathing) and redundant physical connections, which provide active-active or active-passive failover without disrupting the SAN.

Answer

Implement FCoE to Ethernet storage.

Answer

Enable NPIV on all ports.

Answer

Configure a port channel between the switches.

Question 2

Which TWO statements about Fibre Channel zoning are correct? (Choose two.)

Accepted Answer

Zoning can be used to prevent unauthorized access to storage targets.. Fibre Channel zoning restricts which initiators can communicate with which targets, effectively preventing unauthorized access to storage LUNs. By defining zone members (via WWN or port ID), the fabric enforces these access controls at the switch level, ensuring that only devices within the same zone can exchange Fibre Channel frames.

Answer

Zoning is required to increase the distance between a host and storage.

Answer

Zoning can only be applied within a single VSAN.

Answer

Zoning is used to load balance traffic across multiple paths.

Question 3

Which THREE factors should be considered when calculating the required number of buffer credits for a long-distance Fibre Channel link? (Choose three.)

Accepted Answer

The link data rate (e.g., 16 Gbps).. Buffer credits are calculated using the link data rate (affects how many bits can be transmitted per second), the maximum frame size (determines how many bytes are consumed per credit), and the distance between switches (affects propagation delay and round-trip time). Therefore, options A (data rate), B (frame size), and E (distance) are correct. VSAN count (C) and zone count (D) have no impact on buffer credit calculations.

Answer

The number of VSANs configured.

Answer

The number of zones in the fabric.

Question 4

Which TWO statements about NPV (N_Port Virtualization) are correct? (Choose two.)

Accepted Answer

NPV allows a NPV switch to forward traffic from multiple host ports to the core switch via a few uplinks.. NPV (N_Port Virtualization) allows a NPV switch to aggregate traffic from multiple host ports (NP ports) and forward it to the core switch via a few uplinks (NP uplinks). This reduces the number of physical connections required between edge and core switches, simplifying cabling and management.

Answer

NPV uses Inter-VSAN Routing (IVR) to forward traffic between VSANs.

Answer

NPV requires FCoE encapsulation.

Answer

NPV allows a single physical port to have multiple N-port IDs.

Question 5

A Fibre Channel switch port is experiencing high latency due to insufficient buffer credits. What is the most likely cause?

Accepted Answer

Long-distance link between switches. In Fibre Channel (FC) networks, buffer credits are a flow control mechanism that allows a sender to transmit frames without waiting for an acknowledgment. Long-distance links require more buffer credits to keep the link fully utilized because the round-trip time (RTT) is higher. If insufficient buffer credits are allocated, the port will experience high latency as it must wait for credits to be returned before sending more frames.

Answer

CRC errors on the fibre optic cable

Answer

High oversubscription ratio on the port

Answer

VSAN ID mismatch between end devices

Question 6

An administrator notices that a new server connected to a Fibre Channel switch cannot log in. The 'show flogi database' command does not show the server's WWPN. What is the most likely cause?

Accepted Answer

Port security enabled with WWN mismatch. The 'show flogi database' command lists all devices that have successfully completed the Fabric Login (FLOGI) process. If the server's WWPN is absent, it indicates that the FLOGI request was rejected by the switch. Port security with a WWN mismatch is the most likely cause because the switch is configured to allow only specific WWPNs, and the server's WWPN does not match the allowed list, causing the switch to silently drop the FLOGI request without logging the device.

Answer

Trunking mode not enabled on the port

Answer

Incorrect zoning configuration

Answer

Speed mismatch between the server and switch

Question 7

A data center uses FCoE on Nexus 9000 switches. The storage team reports inconsistent performance during peak times. Queuing drops are seen on the FCoE-enabled interfaces. Which QoS configuration change would best address the issue?

Accepted Answer

Ensure sufficient buffer allocation for the no-drop class. In FCoE networks, lossless behavior is required for storage traffic, which is enforced by priority flow control (PFC) on the no-drop class. Queuing drops on FCoE-enabled interfaces indicate that the no-drop class is experiencing buffer exhaustion under congestion. Increasing buffer allocation for the no-drop class ensures that FCoE frames are not dropped, maintaining the lossless fabric required by Fibre Channel over Ethernet.

Answer

Enable WRED on the FCoE class

Answer

Increase MTU on the FCoE VLAN

Answer

Increase the number of pause frames on the no-drop class

Question 8

An engineer needs to isolate storage traffic for different departments using Fibre Channel switches. Which technology should be used?

Accepted Answer

VSAN (Virtual SAN). VSAN (Virtual SAN) is the correct technology because it allows the engineer to create multiple isolated virtual SANs on a single physical Fibre Channel fabric. Each VSAN operates as an independent SAN with its own fabric services, security policies, and traffic isolation, enabling different departments to have dedicated storage traffic without interference.

Answer

Zoning

Answer

Trunking

Answer

NPV (N-Port Virtualization)

Question 9

A data center uses NPV to connect edge switches to a core Fibre Channel switch. The edge switches report that some servers cannot log in. What is a likely cause?

Accepted Answer

NPIV not enabled on the core switch. In an NPV environment, the edge switch (NPV mode) relies on the core Fibre Channel switch to handle fabric login (FLOGI) and name server registration. NPIV (N_Port ID Virtualization) must be enabled on the core switch to allow multiple N_Port IDs to be assigned to a single physical N_Port, which is essential for NPV to function. If NPIV is not enabled on the core, the core switch cannot accept FLOGI requests from the NPV edge switch, preventing servers from logging into the fabric.

Answer

Overlapping VSAN IDs between edge and core

Answer

F port binding on the edge switch

Answer

Trunking mode not enabled on the core switch

Question 10

An iSCSI SAN is experiencing performance issues. The storage array and initiators are connected via a dedicated VLAN. The network team notices high jitter. What is the most effective mitigation?

Accepted Answer

Implement QoS to give iSCSI traffic higher priority. High jitter indicates variable latency in the network, which is detrimental to iSCSI performance because iSCSI relies on TCP and is sensitive to delay variation. Implementing QoS to prioritize iSCSI traffic ensures consistent low-latency delivery by marking iSCSI frames (e.g., with DSCP CS4 or AF41) and queuing them ahead of other traffic, directly mitigating jitter. This is the most effective mitigation because it addresses the root cause—uncontrolled network congestion—rather than increasing parallelism or frame size.

Answer

Use multiple iSCSI sessions per initiator

Answer

Configure link aggregation between switches

Answer

Enable jumbo frames on all switches

Question 11

An NFS client is unable to write to a mounted export. The client can read files. What is the most likely cause?

Accepted Answer

Export permissions are read-only for the client. The NFS export permissions are configured on the NFS server using the /etc/exports file. If the export is set to 'ro' (read-only) for the client's IP or subnet, the client can read files but any write attempt will be denied at the server level, regardless of the client's mount options. This is the most direct cause of a client being able to read but not write.

Answer

Network latency causing timeouts

Answer

Incorrect mount options (e.g., ro instead of rw)

Answer

NFS version mismatch

Question 12

A Fibre Channel fabric has multiple initiators and targets. The engineer wants to ensure that only specific hosts can access specific storage volumes. Which zoning practice is most secure?

Accepted Answer

Single-initiator zoning with WWPNs. Single-initiator zoning with WWPNs is the most secure practice because it creates a one-to-one mapping between a single initiator and its target(s) using the globally unique World Wide Port Name. This eliminates any possibility of unauthorized access or interference from other initiators, as each zone contains exactly one initiator, preventing any form of 'spoofing' or 'zoning overlap' that could allow a rogue host to access storage volumes it should not see.

Answer

Zoning by storage array aliases

Answer

Using VSANs instead of zones

Answer

Soft zoning with domain/port IDs

Question 13

An FCoE link between a Nexus switch and a storage array fails to come up. The switch is configured as an FCF. The administrator runs 'show interface ethernet 1/1' and sees the interface is up/up. Which command will most likely reveal the root cause?

Accepted Answer

show fcoe database. The FCoE link failing to come up despite the interface being up/up indicates a Layer 2 or FCoE-specific issue, not a physical or basic connectivity problem. The 'show fcoe database' command displays the FCoE login information and the state of virtual links (VFCs) mapped to the physical interface, which is essential for diagnosing why the FCF-to-storage array FCoE session is not established.

Answer

show vlan id 100

Answer

show lldp neighbors interface ethernet 1/1

Answer

show spanning-tree interface ethernet 1/1

Question 14

Which TWO benefits does NPIV (N_Port ID Virtualization) provide in a Fibre Channel SAN? (Choose two.)

Accepted Answer

Enables Fibre Channel connectivity for virtual machines. NPIV allows a single physical N_Port to register multiple N_Port IDs (FCIDs) with the Fibre Channel fabric. This enables each virtual machine on a virtualized server to have its own unique WWN and FCID, providing direct Fibre Channel connectivity to storage without requiring a dedicated physical HBA per VM. By sharing a single physical port among multiple VMs, NPIV reduces the number of physical ports and HBAs needed in virtualized environments.

Answer

Enhances security by isolating traffic at the port level

Answer

Increases throughput by aggregating bandwidth

Answer

Allows multiple VSANs on a single link

Question 15

Which THREE conditions can cause Fibre Channel buffer credit starvation? (Choose three.)

Accepted Answer

Frequent CRC errors causing retransmissions. Frequent CRC errors indicate corrupted frames, which require retransmission. Each retransmission consumes an additional buffer credit, effectively starving the port of available credits for new transmissions. This leads to reduced throughput and potential credit starvation.

Answer

High oversubscription ratio on the ISL

Answer

Multiple VSANs configured on the same trunk