EMC D-XTR-DY-A-24 Exam With Confidence Using Practice Dumps

Backup Policy and XtremIO Virtual Copy: The system administrator needs to ensure that the backup policy using XtremIO Virtual Copy (XVC) can store the required read-only copies without exceeding the storage limits.

Calculating Days of Storage:

500 production volumes are backed up 4 times a day.

Total copies created per day: 500 volumes * 4 backups/day = 2000 copies/day.

Assuming the array can store a specific number of copies before older ones are deleted, let's determine the duration:

Duration Calculation:

If the array can store copies for 5 days, it can handle: 2000 copies/day * 5 days = 10,000 copies.

Thus, the array can store the backup copies for 5 days before the original backups are deleted to make space for new ones.

References:

Dell XtremIO 6.x User Guide

XtremIO Virtual Copy and Protection Copies Features

Dell XtremIO Deployment Services

In XtremIO, snapshots are created efficiently using metadata rather than duplicating the actual data blocks. When a snapshot is made, it initially shares the same data blocks as its ancestor. When the first write occurs to a block in a snapshot, it triggers a Copy-On-First-Write (COFW) operation. This means the original data block is copied to a new location to preserve the integrity of the snapshot, ensuring that each snapshot reflects the data state at the moment of its creation.

This COFW operation ensures that the data remains consistent and unchanged for each snapshot, while allowing new writes to occur without impacting the original data or other snapshots. As a result, the first write to each snapshot impacts its ancestor by triggering a COFW operation.

References:

Dell XtremIO Deployment and Learning Course Materials

The “Small IO Alerts” feature in XtremIO is designed to notify administrators when a significant number of small I/O operations are detected, which could potentially impact the performance of the storage array. The threshold for these alerts is typically set to a default value that considers the architecture and performance characteristics of the system. In the case of XtremIO, the alert is triggered when I/O operations are smaller than 4 KB1. This threshold is set based on the understanding that smaller I/O sizes can lead to inefficient utilization of the storage array’s resources and can be an indicator of suboptimal application behavior or configuration.