350-601 Storage Network Practice Test 5 — 15 Questions

Question 1

During a SAN performance analysis, a Fibre Channel link shows a high number of CRC errors. The link operates at 16 Gbps over a 10 km dark fiber. Which corrective action is least likely to resolve the issue?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Increase the buffer-to-buffer credit count on the link.. CRC errors on a Fibre Channel link indicate physical-layer corruption — bad optics, dirty connectors, damaged fiber, or mismatched optics/fiber type. Buffer-to-buffer credits are a flow-control mechanism that governs how many frames a port can send before receiving acknowledgment; they affect throughput and congestion, not signal integrity. Therefore, increasing credits will not resolve CRC errors, making it the least likely corrective action.

Answer

Replace the fiber cable with a single-mode fiber cable if multimode is used.

Answer

Clean all fiber connectors and inspect for damage.

Answer

Verify that the SFP+ optics match the fiber type and distance.

Question 2

Which TWO conditions require the use of NPIV in a Fibre Channel SAN? (Choose two.)

Accepted Answer

Connecting a tape library that uses multiple LUNs to a single host.. Option A is correct because NPIV (N_Port ID Virtualization) allows a single physical HBA port to register multiple virtual N_Port IDs (WWPNs), which is required when a tape library with multiple LUNs must be presented to a single host through one physical port. Option E is correct because server virtualization platforms use NPIV to assign each virtual machine its own unique WWPN, enabling per-VM zoning and LUN masking on the SAN fabric. Option B is incorrect because connecting an NPV (N_Port Virtualization) switch to an upstream switch uses NPV, not NPIV, on the edge switch. Option C is incorrect because FCoE transit over lossless Ethernet relies on DCB/PFC and FIP, not NPIV. Option D is incorrect because inter-switch links (ISLs) between Fibre Channel switches use E_Ports and standard fabric services, not NPIV.

Answer

Connecting an NPV switch to an upstream switch.

Answer

Enabling FCoE transit over a lossless Ethernet network.

Answer

Connecting two switches over an ISL.

Question 3

Which TWO commands are used to verify zoning configuration on a Cisco MDS switch? (Choose two.)

Accepted Answer

show zone. The 'show zone' command displays the configured zone database, including zone members and their aliases, which is essential for verifying zoning configuration. The 'show zoneset active' command shows the currently active zoneset that is enforced by the switch, confirming which zones are actually applied to traffic. Both commands directly verify zoning configuration on a Cisco MDS switch.

Answer

show fcns database

Answer

show flogi database

Answer

show vsan membership

Question 4

A large enterprise data center has a disaster recovery site 100 km away. The SAN uses two MDS 9700 series switches at each site, connected via a dedicated dark fiber. Each link operates at 16 Gbps with a round-trip time of 2 ms. Recently, backup jobs to the remote storage array have been failing with timeout errors. The backup server is local to Site A, but the backup target is in Site B. The link utilization never exceeds 40%, and no errors are reported on the interfaces. The engineer suspects the issue is related to buffer credits. The current buffer credit count on the ISL is 16. The engineer calculates that for 16 Gbps over 100 km (2 ms RTT), they need at least 200 credits to maintain full throughput. Which action is most appropriate to resolve the issue?

Accepted Answer

Increase the buffer-to-buffer credit count to 300 on the ISL interfaces.. Fibre Channel buffer-to-buffer credits govern how many frames a port can send before receiving an RTS/ACK from the peer. On a long-distance ISL with 2 ms RTT, the bandwidth-delay product demands far more credits than the default 16 to sustain 16 Gbps. Increasing the credit count to 300 (above the calculated 200 minimum) restores full throughput and eliminates the timeout-induced backup failures.

Answer

Enable NPIV on the ISL ports to allow multiple logins.

Answer

Configure the ISL to operate at 8 Gbps to reduce the buffer credit requirement.

Answer

Implement FCIP over the existing dark fiber to offload buffer credit management.

Question 5

A company is deploying a new storage network using Cisco MDS 9700 switches. They have multiple host servers and storage arrays. The security policy requires that each host can only access its own LUNs. The solution must be efficient and not require reconfiguration when new hosts are added. Which approach best meets these requirements?

Accepted Answer

Smart Zoning. Smart Zoning is correct because it automatically creates LUN-specific access controls based on the host initiator and target storage port, ensuring each host can only see its own LUNs without manual reconfiguration when new hosts are added. This approach reduces the number of zone objects and simplifies management by using LUN-level granularity within a single zone, unlike traditional zoning which requires per-LUN zones.

Answer

Traditional zone-based zoning with pWWNs

Answer

VSAN zoning

Answer

FSPF metric tuning

Question 6

An engineer notices that the CPU utilization on a Cisco Nexus 5548UP switch is consistently above 80%. The switch is used for FCoE storage traffic. Which action is most likely to reduce CPU utilization?

Accepted Answer

Reduce the number of FCoE VLANs. High CPU utilization on a Cisco Nexus switch handling FCoE storage traffic is often caused by excessive FCoE Initialization Protocol (FIP) keepalive processing. Reducing the number of FCoE VLANs directly decreases the number of FIP sessions and associated control-plane overhead, lowering CPU load. This is the most effective action because each FCoE VLAN requires separate FIP keepalive handling, and consolidating storage traffic into fewer VLANs reduces the control-plane burden.

Answer

Configure DCBx will-say mode

Answer

Enable FCoE NPV mode

Answer

Disable FIP snooping

Question 7

An administrator is troubleshooting a performance issue in an FC SAN. The initiator and target are in the same VSAN. The link is 16 Gbps but throughput is only 4 Gbps. The engineer checks the BB_Credit utilization and sees a high count of BB_Credit zero. What is the most likely cause?

Accepted Answer

Buffer-to-buffer credit exhaustion. BB_Credit zero indicates buffer-to-buffer credit exhaustion, which pauses transmission and reduces throughput. This is typically due to distance or small credit pool. Link errors would show CRC errors, congestion would cause other symptoms, and zoning is unrelated.

Answer

Congestion on the target port

Answer

High link error rates

Answer

Incorrect zoning configuration

Question 8

Which TWO of the following are benefits of using Smart Zoning in Cisco MDS switches?

Accepted Answer

Reduces number of zone objects. Option A is correct because Smart Zoning creates a single smart zone per initiator-target pair instead of generating the many individual zones and zone members that traditional zoning requires, thereby reducing the total number of zone objects in the active zone set. Option C is correct because this reduction in zone objects and members, combined with the ability to define zones using a single smart zone construct, makes zone administration far simpler and more scalable in large fabrics with many initiators and targets. Option B is incorrect because faster FLOGI processing is not a Smart Zoning benefit; FLOGI handling relates to fabric login and name server operations, not zone object optimization. Option D is incorrect because Smart Zoning operates within VSANs and does not replace them; VSANs remain the fundamental fabric isolation mechanism on MDS switches. Option E is incorrect because LUN masking is performed by storage arrays or by features such as IVR/zoning at the host-storage level, not automatically by Smart Zoning.

Answer

Provides faster FLOGI processing

Answer

Eliminates the need for VSANs

Answer

Allows automatic LUN masking

Question 9

A data center uses a Cisco MDS 9710 director with multiple line cards. The storage network includes several host servers connected to the director via 16 Gbps FC connections. Recently, the engineering team deployed a new storage array that supports 32 Gbps FC. To take advantage of the higher speed, they upgraded the host HBAs to 32 Gbps. However, after the upgrade, some hosts are experiencing intermittent connection drops. The team notices that when a host disconnects, it takes approximately 30 seconds to reconnect. The link lights on the host and switch ports are green. The switch logs show 'VSAN 100: Port fc1/1 is down (link failure)' messages. No other errors are reported. The MDS line cards support 32 Gbps, and the ports are configured with the 'speed 32000' command. What is the most likely cause of the intermittent drops?

Accepted Answer

Mismatched port speed configuration between host and switch. The most likely cause is a mismatched port speed configuration between the host and switch. Although the line cards support 32 Gbps and the ports are configured with 'speed 32000', the host HBAs may not be configured for 32 Gbps, or the switch ports may not be negotiating correctly. This mismatch can cause intermittent link failures and reconnections.

Answer

Insufficient buffer credits on the host ports

Answer

Incompatible SFP+ modules

Answer

Inconsistent zoning configuration

Question 10

A large enterprise uses Cisco Nexus 5548UP switches in FCoE mode. The storage array is connected via native FC to an MDS 9700. The FCoE switches are connected to the MDS via FC uplinks. Recently, the storage team deployed a new FCoE initiator that requires access to a specific LUN. After configuring the zone and VSAN, the initiator cannot discover the target. The zone includes the pWWN of the target and the FCoE initiator's pWWN (derived from its MAC address). The initiator is in VSAN 100, and the target is in the same VSAN. The MDS show flogi database shows the initiator. The show fcoe database on the Nexus shows the initiator but the session is not active (state: FIP-VN_Port not logged in). The engineer checks the FIP snooping policy and notices that the FCoE VLAN to VSAN mapping is correct. What is the most likely issue?

Accepted Answer

The FIP snooping policy is blocking the FLOGI. The Nexus show fcoe database shows the initiator with state 'FIP-VN_Port not logged in,' meaning the FIP (FCoE Initialization Protocol) exchange completed discovery but the FLOGI did not complete. Since the FCoE VLAN-to-VSAN mapping is correct and the MDS sees the initiator in its flogi database, the most likely cause is that the FIP snooping policy on the Nexus is blocking the FLOGI, preventing the VN_Port from logging in.

Answer

The MDS does not have a route to the FCoE initiator's VSAN

Answer

The FCoE initiator is not using the correct VN_Port MAC address

Answer

The FCoE NPV is not enabled on the Nexus

Question 11

A small business has a Cisco MDS 9148S switch with a single fabric. Two hosts are connected to ports fc1/1 and fc1/2, and a storage array is connected to ports fc1/3 and fc1/4. The administrator wants to ensure that each host can only see its own assigned LUNs on the array. They have configured a zone for each host containing the host pWWN and the target pWWN for the respective LUNs. However, Host A is able to see Host B's LUNs. What is the most likely cause?

Accepted Answer

The zoning configuration is using a zone alias that includes both hosts. The administrator likely used a zone alias that inadvertently includes both hosts' pWWNs. In Cisco MDS zoning, a zone alias is a named set of pWWNs; if the alias contains both Host A and Host B, then any zone using that alias will include both hosts, allowing Host A to see Host B's LUNs. This violates the intended hard-zoning isolation, as zones must contain only the specific host-target pairs to enforce LUN masking.

Answer

The zone is not active

Answer

The zones are not in the same VSAN

Answer

The target ports are using soft zoning

Question 12

An organization has four Cisco MDS 9700 directors connected in a full-mesh topology. They use VSANs to separate production, backup, and management traffic. The backup VSAN is experiencing high latency and occasional timeouts. The engineer runs the 'show fcspf routes' command and notices that the path from the backup host to the backup target has an uneven hop count across different paths. The links are all 16 Gbps. The engineer also notes that the backup target is connected to a different director than the backup host. Which action is most likely to improve performance?

Accepted Answer

Decrease the FSPF cost on the direct links. Decreasing the FSPF cost on the direct links encourages traffic to take shorter paths, reducing hop count and latency. Increasing cost would push traffic away, making it worse. IVR is for inter-VSAN routing, not intra-VSAN. Load balancing via PortChannels increases bandwidth but does not directly reduce latency from long paths.

Answer

Configure IVR to route backup traffic over a dedicated path

Answer

Increase the FSPF cost on the direct links

Answer

Implement load balancing using multiple PortChannels

Question 13

A large data center uses a Cisco Nexus 9000 switch with FCoE NPV feature. The switch is connected to an MDS 9700 upstream. The network team recently replaced the MDS 9700 with a new one. After the replacement, the FCoE hosts are unable to log in to the storage fabric. The Nexus switch shows that the FCoE NPV uplinks are up but no FLOGIs are being forwarded. The show npv flogi-table on the Nexus is empty. The upstream MDS shows that the uplinks are in VSAN 100, and the zoning is correct. The Nexus switch configuration includes 'feature npv' and 'npv enable' on the relevant interfaces. The FCoE VLAN 100 is mapped to VSAN 100. What is the most likely cause?

Accepted Answer

The upstream MDS is not configured to accept NPV connections. For FCoE NPV to function, the upstream switch (the MDS 9700 in this case) must be explicitly configured to accept NPV connections — typically by enabling NPIV/NPV on the core switch and configuring the correct VSAN membership and port roles. When the MDS was replaced, the new MDS likely lacks the NPV/NPIV configuration on the ports facing the Nexus, so the Nexus NPV uplinks come up at the link level but the upstream fabric never accepts the FLOGI proxy requests. Since the Nexus 'show npv flogi-table' is empty and the uplinks are up, the failure is at the upstream authentication/registration stage, not at the Nexus side.

Answer

The FIP snooping policy is blocking the FLOGI traffic

Answer

The Nexus switch is missing the 'fcoe fka-adv-period' configuration

Answer

The FCoE hosts are not in the same VLAN as the FCoE NPV uplinks

Question 14

A new storage administrator is configuring LUN masking on a Cisco MDS switch. The storage array presents two LUNs to the fabric with the same LUN ID (0) but to different target ports. The administrator wants to ensure that a specific host can access both LUNs. The host is connected to a single HBA port. The host will see both target ports in the same zone. After zoning, the host discovers both target ports but only sees the first LUN. The show flogi database shows the host's pWWN with two FC IDs assigned. What is the most likely issue?

Accepted Answer

The target LUNs are not masked to the host's pWWN. The host discovers both target ports via FLOGI but only sees the first LUN because the storage array has not been configured to mask the LUNs to the host's pWWN. LUN masking is an array-side access control that determines which initiator WWNs can see which LUNs; without it, the array defaults to presenting only the first LUN (LUN 0) to any initiator. The zone is correctly configured (both target ports are in the same zone and the host sees them), and the LUN ID conflict is irrelevant because the LUNs are on different target ports, so they can share the same LUN ID without conflict.

Answer

The zone is misconfigured

Answer

The host is not configured for multipathing

Answer

There is a LUN ID conflict

Question 15

A storage administrator is troubleshooting a Fibre Channel SAN where initiators cannot log in to a target. The administrator verifies that the VSAN is configured correctly and that zoning is in place. Which two additional checks should be performed to resolve the issue?

Accepted Answer

Confirm that FCID persistence is not enabled with invalid static FCIDs.. In a Fibre Channel SAN, FCID persistence assigns a specific FCID to a device each time it logs in. If an invalid static FCID is configured (e.g., an FCID that conflicts with another device or is outside the allowed range), the initiator may fail to log in because the switch cannot assign the requested address. This is a common cause of login failures even when VSAN and zoning are correctly configured.

Answer

Ensure NPIV is enabled on the F-port.

Answer

Verify the FCoE VLAN ID matches on both ends.

Answer

Check that LUN masking has been applied on the target.