What causes "Invalid data storage: %s Accepted units:%s" in apache/cassandra?

Express the value in a unit at or above the min unit (e.g. convert 512KiB to 1MiB if the min unit is MiB)

apache/cassandra · error · IllegalArgumentException

Invalid data storage: %s Accepted units:%s

Error message

Invalid data storage: %s Accepted units:%s

What it means

validateMinUnit checks that the unit parsed from a DataStorageSpec value is not smaller than the required minimum unit for that spec subclass. If the source unit compares below the min unit (ordinal-wise), it throws this IllegalArgumentException listing only the acceptable units.

Source

Thrown at src/java/org/apache/cassandra/config/DataStorageSpec.java:89

        else
        {
            throw new IllegalArgumentException("Invalid data storage: " + value + " Accepted units:" + acceptedUnits(minUnit) +
                                               " where case matters and only non-negative values are accepted");
        }
    }

    private DataStorageSpec(String value, DataStorageUnit minUnit, long max)
    {
        this(value, minUnit);

        validateMinUnit(unit, minUnit, value);
        validateQuantity(value, quantity(), unit(), minUnit, max);
    }

    private static void validateMinUnit(DataStorageUnit sourceUnit, DataStorageUnit minUnit, String value)
    {
        if (sourceUnit.compareTo(minUnit) < 0)
            throw new IllegalArgumentException(String.format("Invalid data storage: %s Accepted units:%s", value, acceptedUnits(minUnit)));
    }

    private static String acceptedUnits(DataStorageUnit minUnit)
    {
        DataStorageUnit[] units = DataStorageUnit.values();
        return Arrays.toString(Arrays.copyOfRange(units, minUnit.ordinal(), units.length));
    }

    private static void validateQuantity(String value, long quantity, DataStorageUnit sourceUnit, DataStorageUnit minUnit, long max)
    {
        // no need to validate for negatives as they are not allowed at first place from the regex

        if (minUnit.convert(quantity, sourceUnit) >= max)
            throw new IllegalArgumentException("Invalid data storage: " + value + ". It shouldn't be more than " +
                                               (max - 1) + " in " + toLowerCaseLocalized(minUnit.name()));
    }

    private static void validateQuantity(long quantity, DataStorageUnit sourceUnit, DataStorageUnit minUnit, long max)

View on GitHub (pinned to 88fd0f6a0e)

Solutions

Express the value in a unit at or above the min unit (e.g. convert 512KiB to 1MiB if the min unit is MiB)
Read acceptedUnits from the message and pick the smallest listed unit
Use the numeric double-based constructor with an explicit unit when you control the unit programmatically
Add a pre-parse check comparing DataStorageUnit ordinals against the bound's minimum

Example fix

// before
DataStorageSpec.LongStorageBound b = new DataStorageSpec.LongStorageBound("512KiB");
// after
DataStorageSpec.LongStorageBound b = new DataStorageSpec.LongStorageBound("1MiB");

Defensive patterns

Strategy: validation

Validate before calling

DataStorageSpec.DataStorageUnit src = DataStorageSpec.DataStorageUnit.fromSymbol(unitToken);
if (src.compareTo(MIN_UNIT) < 0)
    throw new IllegalArgumentException("Unit " + unitToken + " is below the minimum " + MIN_UNIT);

Try / catch

try {
    bound = new DataStorageSpec.LongStorageBound(value);
} catch (IllegalArgumentException e) {
    logger.error("Storage unit below required minimum for bound: " + value, e);
    bound = new DataStorageSpec.LongStorageBound(convertToMinUnitOrAbove(value));
}

Prevention

Check each bound subclass's minimum unit before formatting its value
Convert small-unit values (B, KiB) up to the minimum unit programmatically
Prefer the numeric constructors with explicit units in code

When it happens

Trigger: Constructing a bounded/extended DataStorageSpec (e.g. DataStorageSpec.LongStorageBound) from a string expressed in a unit below the required min unit, such as '512B' or '10KiB' where the bound requires MiB or larger.

Common situations: Programmatic config building where subclasses impose minimum units; YAML migration code reusing a generic storage string for a bound type that needs a larger unit; test fixtures with tiny values.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/e82c8e5b2898a7be. Report an issue: GitHub.