How to use the command 'quota' (with examples)

The ‘quota’ command is used to display users’ disk space usage and allocated limits. It allows users to monitor their disk usage and be aware of any limitations set by the system administrator. The command provides information about disk quotas in human-readable units, displaying quotas on both filesystems where storage is allocated and where usage is over quota.

Use case 1: Show disk quotas in human-readable units for the current user

Code:

quota -s

Motivation:

This use case is useful for users who want to check their disk space usage and the allocated limits on the current system. By displaying the disk quotas in human-readable units, users can easily understand their usage and available limits.

Explanation:

• ‘-s’: Specifies the ‘summary’ option, which displays disk quotas in human-readable units. It provides a more convenient and readable output for the user.

Example output:

Disk quotas for user johndoe (uid 1001):
     Filesystem  blocks  quota   limit   grace   files   quota   limit   grace
/dev/sda1     50000   200000  250000            130     0       0       

Use case 2: Verbose output (also display quotas on filesystems where no storage is allocated)

Code:

quota -v

Motivation:

This use case is useful when users want to see a detailed overview of their disk quotas, including quotas on filesystems where no storage is allocated. This can help users identify any discrepancies or issues with their disk usage.

Explanation:

• ‘-v’: Specifies the ‘verbose’ option, which provides detailed output including quotas on filesystems where no storage is allocated. It gives a comprehensive overview of the disk quotas for the user.

Example output:

Disk quotas for user johndoe (uid 1001):
     Filesystem   blocks   quota   limit   grace   files   quota   limit   grace
/dev/sda1        50000  200000  250000            130       0       0    
/dev/sdb1           0       0       0                   0       0       0  

Use case 3: Quiet output (only display quotas on filesystems where usage is over quota)

Code:

quota -q

Motivation:

This use case is beneficial when users want to focus only on filesystems where their disk usage exceeds the allocated quota. By displaying quotas only for filesystems where usage is over quota, users can quickly identify and address any potential issues or violations.

Explanation:

• ‘-q’: Specifies the ‘quiet’ option, which provides a simplified output only containing information about filesystems where usage is over quota. It eliminates excessive information and focuses on critical details.

Example output:

Disk quotas for user johndoe (uid 1001):
     Filesystem   blocks   quota   limit   grace   files
/dev/sda1         50000  200000  250000            130    

Use case 4: Print quotas for the groups of which the current user is a member

Code:

quota -g

Motivation:

This use case is useful for users who want to view their disk quotas grouped by the different groups that they belong to. It provides an organized overview of disk quotas for each group, allowing users to manage their disk usage efficiently.

Explanation:

• ‘-g’: Specifies the ‘group’ option, which prints quotas for the groups of which the current user is a member. It groups the disk usage information by user groups, providing a clear breakdown of quotas.

Example output:

Disk quotas for user johndoe (uid 1001):
     Group     soft limit   hard limit     grace     files     soft limit     hard limit     grace
     group1        10000        20000                  60        100        200        
     group2       150000       200000                 10        500        1000      

Use case 5: Show disk quotas for another user

Code:

sudo quota -u username

Motivation:

This use case is useful for system administrators or privileged users who need to check the disk quotas of a specific user on the system. By using the ‘sudo’ command, it allows access to the disk quota information of other users.

Explanation:

• ‘sudo’: Executes the ‘quota’ command with administrative privileges, enabling access to the disk quota information of another user.
• ‘-u username’: Specifies the username of the user whose disk quotas you want to display. Replace ‘username’ with the actual username.

Example output:

Disk quotas for user janedoe (uid 1002):
     Filesystem   blocks   quota   limit   grace   files   quota   limit   grace
/dev/sda1        25000  100000  150000            80       0       0      

Conclusion:

The ‘quota’ command provides users with essential information about their disk space usage and allocated limits. By understanding how to use different options, such as displaying disk quotas in human-readable units, retrieving detailed or simplified output, and checking disk quotas for specific users or groups, users can effectively monitor and manage their disk usage.