A storage administrator would like to connect 10 hosts into the same FC ports of a Hitachi Unified Storage system. They are concerned that one host with high I/Os will impact the other hosts on the…

Question

Options

• Aqueue depth
• Bcommand length
• Ccommand depth
• Dqueue length

• A
  83% (39)
• B
  2% (1)
• C
  11% (5)
• D
  4% (2)

Explanation

Queue depth (A) is the HBA parameter that controls how many I/O commands a single host can have outstanding (in-flight) to a storage target at one time. By lowering the queue depth on each host's HBA, the administrator ensures no single host can flood the shared FC ports with excessive I/Os, protecting all hosts from a "noisy neighbor" scenario.

B (command length) refers to the size/structure of a SCSI command descriptor block - it has nothing to do with limiting concurrent I/Os. C (command depth) is not a standard HBA parameter; it's a fabricated distractor combining real terms. D (queue length) is sometimes confused with queue depth but typically refers to OS-level software queues (e.g., Linux nr_requests), not the HBA-level throttle that limits per-host outstanding I/Os to the storage array.

Memory tip: Think of "queue depth" like lanes at a toll booth - it sets how many cars (I/Os) one driver (host) can have in the queue at once, preventing one aggressive driver from blocking everyone else.

No community discussion yet for this question.