D-ISM-FN-01 Dell Information Storage and Management Foundations v2 Exam Questions and Answers

Astorage nodeis a component in a backup architecture that handles the actualdata movementduring the backup process:

Itorganizesthe backup data stream.

Itwritesthe data to the backup target (disk, tape, or cloud).

It does not manage policies or schedules (that’s the role of the backup server or management console).

Option A:Monitoring is done by the backup server or management tools.

Option C:Backup management (scheduling, policies) is also handled by the backup server.

Option D:Deduplication may be part of the process but is not theprimary roleof a storage node.

The exhibit shows a Fibre Channel (FC) switch connected to another FC switch. The port "X" is used for inter-switch link (ISL) connectivity, which is characteristic of anE_port (Expansion Port).

F_port (Fabric port):Connects an N_port (host or storage device) to a switch.

N_port (Node port):End device port in FC networks (like HBA in hosts or storage).

NL_port (Node Loop port):Used for Arbitrated Loop topologies.

E_port:Connects two FC switches together for ISL, which is exactly what's shown in the exhibit.

AnF_port (Fabric port)is used on a Fibre Channel switch to connectN_ports (Node ports)on end devices like servers and storage arrays.

N_port:On the compute system (HBA).

F_port:On the switch, accepting N_port connections.

E_port:For switch-to-switch ISL (Inter-Switch Link) connections.

G_port:A generic port that can operate as either an F_port or an E_port (not the direct answer in this scenario).

Rebuilding a RAID 5 array after a disk failure depends on:

Capacity of the failed disk (C)– More data means longer rebuild time.

Write performance of the remaining disks (B)– Rebuild involves recalculating parity and writing data to the replacement disk, which stresses the surviving disks.

Network bandwidth (A)is only relevant for accessing the array, not for internal rebuild operations.

Cache capacity (D)helps performance in some scenarios, but the direct factors are disk size and performance.

TheTransport layer (Layer 4)of the OSI model ensures reliable data transfer between systems by providing:

End-to-end connections– manages communication sessions

Sequencing– orders data packets

Integrity– error detection and correction

Session (Layer 5): Manages sessions and controls dialogues between systems.

Data Link (Layer 2): Deals with local network frame delivery.

Presentation (Layer 6): Translates data formats (like encryption, compression).

ACDP appliancesits in the data path and:

Intercepts all writesto the production volume.

Splits each write into two copies: one goes to the production volume, the other to the replica volume.

Maintains a journal for point-in-time recovery.

Option A/B/C: These are aspects of replication, but CDP’s primary function is real-time interception and splitting of writes.

Data archiving involves moving infrequently accessed data to a separate storage system, freeing up space on primary storage and reducing costs. It also aids in compliance by retaining data for specified periods, as required by various regulations.

Data backup:Creates copies of data for recovery purposes but doesn't necessarily reduce primary storage usage.

Data archiving:Moves less frequently accessed data to cost-effective storage, aiding compliance and reducing primary storage costs.

Data encryption:Secures data but doesn't impact storage costs or compliance retention.

Data compression:Reduces data size but may not meet compliance requirements for data retention.

RAID 5provides acost-effective balancebetween:

Data protection(single parity, can tolerate one disk failure).

Performance(especially read-heavy environments).

Cost(uses fewer drives than RAID 1 or 6 for the same capacity).

RAID 1 (B): Best for read-heavy workloads but doubles the storage needed (mirroring).

RAID 0 (C): No protection against disk failure.

RAID 6 (D): More protection (dual parity), but more write penalty and more disks needed.

Inwrite-through caching, data is written simultaneously to both the cache and the underlying disk. This ensures data integrity because the write is not acknowledged until it’s safely written to the disk.

Write-backcaching offers reduced latency but increases risk of data loss if cache is lost.

Write-throughtrades speed for security, offeringenhanced data securityand reducing the risk of data loss during power failures.

To implement anFC-NVMe SAN(NVMe over Fibre Channel), you need:

NVMe storage systemsthat expose NVMe namespaces.

FC-NVMe capable switchesthat support the new NVMe protocol over Fibre Channel.

Servers with NVMe HBAs(already mentioned in the question).

Option B:Ethernet networks are for NVMe-oF over TCP/RoCE, not FC-NVMe.

Option E:These drivers are for TCP/RoCE, not FC transports.

Aread missoccurs when the data requested by the host isnotavailable in the cache. As a result, the storage system must fetch the data from the slower disk storage (back-end), leading to higher latency.

Cache hit:Data is already in cache → faster response.

Cache miss (read miss):Data not in cache → fetched from the disk.

OSD gateways provide access to object storage systems through APIs. The most common interfaces are:

REST (Representational State Transfer): A stateless protocol using standard HTTP methods, widely used for web services.

SOAP (Simple Object Access Protocol): A protocol for exchanging structured information in web services, using XML.

These APIs allow applications to interact with object storage systems over HTTP/HTTPS protocols.

SSH and SMB: SSH is for secure shell access; SMB is for file sharing, not typically used for object storage.

HTTP and HTTPS: These are transport protocols; while used by REST and SOAP, they are not interfaces themselves.

NFS and CIFS: File-based interfaces, not used for object storage.

FCIP(Fibre Channel over IP) encapsulatesFibre Channel framesinto IP packets and tunnels them over IP networks. This enables remote SAN connectivity across IP-based WANs while preserving FC protocols.

Over Ethernetis inaccurate because FCIP uses IP-level transport (Layer 3), not just Layer 2.

Splitting LAN and FC SAN datais irrelevant to the tunneling mechanism.

Separating LAN/SAN dataalso misses the encapsulation focus.

Data Center Bridging (DCB)is a set of IEEE standards designed to enhance Ethernet for converged data center networks.

DCB includespriority-based flow control (PFC)toreduce frame lossduring congestion.

Ensureslossless Ethernet transport, crucial for storage traffic (like FCoE).

QoS (A)prioritizes traffic but doesn’t guarantee lossless transport.

NAT (C)translates IP addresses, not relevant to lossless transport.

VLAN (D)segments networks logically but doesn’t address congestion.

NAS systemsare purpose-built to handle file sharing and provide:

Centralized file accessfor multiple clients.

Optimized file sharingthrough dedicated hardware and software.

Efficient managementwith file-level protocols (NFS, CIFS/SMB).

FC protocols(Option B) are for block storage, not NAS.

Object ID(Option C) relates to object storage, not NAS.

Speed (Option D): While NAS can offer good speed, its main advantage is shared file access.