How to Use the Command 'dysk' (with Examples)

The dysk command is a useful utility for managing and displaying filesystem information in a table format. It is especially helpful for system administrators and users who need to monitor and analyze disk usage and configuration across different storage devices. With a variety of options for filtering and sorting, dysk allows users to gain insights into disk utilization, identify storage types, and manage space efficiently. The following examples illustrate how to use dysk to achieve different objectives.

Use Case 1: Get a Standard Overview of Your Usual Disks

Code:

dysk

Motivation:

Running the basic dysk command without any additional arguments provides a comprehensive overview of all connected disks and their corresponding information. This is often the first step for users trying to understand their disk setup, as it presents a straightforward view of sizes, usage, and types.

Explanation:

The command dysk without any additional options outputs a table with default columns of disk information such as device names, total sizes, used and free space, file system types, mount points, and more. It is a quick way to get an overall sense of the disk environment.

Example Output:

Device    Size   Used  Free  Type  Mount Point
/dev/sda1 500GB  300GB 200GB ext4  /
/dev/sdb1 1TB    700GB 300GB ext4  /data
/dev/sdc1 250GB  50GB  200GB ntfs  /mnt/backup

Use Case 2: Sort by Free Size

Code:

dysk --sort free

Motivation:

Sorting disks by free size is particularly useful for users who are managing multiple disks and want to quickly identify which disks are running low on space or have ample space available for new data storage. This can help in planning storage expansion or data migration strategies.

Explanation:

• --sort free: This option tells dysk to sort the output by the amount of free space available on each disk. By presenting this insight, users can easily spot underutilized or overburdened disks.

Example Output:

Device    Size   Used  Free  Type  Mount Point
/dev/sdb1 1TB    700GB 300GB ext4  /data
/dev/sdc1 250GB  50GB  200GB ntfs  /mnt/backup
/dev/sda1 500GB  300GB 200GB ext4  /

Use Case 3: Include Only HDD Disks

Code:

dysk --filter 'disk = HDD'

Motivation:

There might be specific situations where a user is only interested in information pertaining to traditional HDDs, such as when assessing older systems or specific applications where HDD performance is a critical factor. Filtering to show only HDDs eliminates irrelevant information about SSDs or other drive types.

Explanation:

• --filter 'disk = HDD': This filter option confines the output to only those disks identified as hard disk drives (HDD). This is achieved by applying a conditional expression to match disks of this type exclusively.

Example Output:

Device    Size   Used  Free  Type  Mount Point
/dev/sda1 500GB  300GB 200GB ext4  /

Use Case 4: Exclude SSD Disks

Code:

dysk --filter 'disk <> SSD'

Motivation:

In some scenarios, users might want to exclude SSDs from their analysis to focus on other types of storage devices, perhaps for documentation or migration projects where SSDs are irrelevant. This helps in narrowing down the list to relevant disks only.

Explanation:

• --filter 'disk <> SSD': This command filters out disks that are SSDs, allowing users to focus on other storage types by using the non-equality operator (<>).

Example Output:

Device    Size   Used  Free  Type  Mount Point
/dev/sda1 500GB  300GB 200GB ext4  /

Use Case 5: Display Disks with High Utilization or Low Free Space

Code:

dysk --filter 'use > 65% | free < 50G'

Motivation:

Monitoring disks for high utilization or limited free space is crucial for preventing potential system issues, such as run-out-of-space errors, which can lead to service disruptions. This filter helps to quickly identify disks that are at risk, taking preemptive measures to manage storage effectively.

Explanation:

• --filter 'use > 65%': This part of the filter selects disks where more than 65% of the space is in use.
• | free < 50G': The pipe operator (|) expands the filter criteria, including any disks with less than 50GB of free space. It effectively combines both filters to catch disks triggering either condition.

Example Output:

Device    Size   Used  Free  Type  Mount Point
/dev/sdb1 1TB    750GB 250GB ext4  /data
/dev/sdc1 250GB  205GB 45GB  ntfs  /mnt/backup

Conclusion:

The dysk command offers a versatile and powerful way to probe disk information and manage storage systems. Whether needing a quick overview or a detailed examination based on specific criteria like space utilization or disk type, dysk provides users with the tools necessary to understand and effectively manage their filesystem resources.