elastic/elasticsearch · error · IllegalArgumentException

failed to parse setting [{}] with value [{}] as a time value

Error message

failed to parse setting [{}] with value [{}] as a time value: negative durations are not supported

What it means

Thrown by TimeValue.parse when a setting's numeric component parses as a valid long but is less than -1. The value -1 is reserved as a magic sentinel (typically meaning 'disabled' or 'unbounded'); every other negative duration is rejected because negative time has no meaningful interpretation for a timeout or interval. The error names the setting and echoes the original (un-normalized) input so the offending config line is identifiable.

Source

Thrown at libs/core/src/main/java/org/elasticsearch/core/TimeValue.java:416

        } else if (normalized.matches("-0*1")) {
            return TimeValue.MINUS_ONE;
        } else if (normalized.matches("0+")) {
            return TimeValue.ZERO;
        } else {
            // Missing units:
            throw new IllegalArgumentException(
                "failed to parse setting [" + settingName + "] with value [" + sValue + "] as a time value: unit is missing or unrecognized"
            );
        }
    }

    private static long parse(final String initialInput, final String normalized, final String suffix, String settingName) {
        final String s = normalized.substring(0, normalized.length() - suffix.length()).trim();
        try {
            final long value = Long.parseLong(s);
            if (value < -1) {
                // -1 is magic, but reject any other negative values
                throw new IllegalArgumentException(
                    "failed to parse setting ["
                        + settingName
                        + "] with value ["
                        + initialInput
                        + "] as a time value: negative durations are not supported"
                );
            }
            return value;
        } catch (final NumberFormatException e) {
            try {
                @SuppressWarnings("unused")
                final double ignored = Double.parseDouble(s);
                throw new IllegalArgumentException("failed to parse [" + initialInput + "], fractional time values are not supported", e);
            } catch (final NumberFormatException ignored) {
                throw new IllegalArgumentException("failed to parse [" + initialInput + "]", e);
            }
        }
    }

View on GitHub (pinned to db6a809a66)

Solutions

1. Set the value to a positive duration (e.g. "30s", "5m") or to -1 if the setting treats -1 as disabled/unbounded.
2. If the value comes from a computed variable, clamp it: value = Math.max(-1, computed) before formatting the string.
3. Audit the offending setting name in the error message against elasticsearch.yml or the index/cluster settings API to locate the bad input.
4. If you genuinely need 'no timeout', use -1 (and confirm the specific setting honors the -1 sentinel — not all do).

Example fix

// before
index.cache.query.size: -5m

// after
index.cache.query.size: -1   // -1 = disabled; or a positive duration like 10m

// Validate a candidate time-value string before passing to TimeValue.parseTimeValue
private static final Pattern TV = Pattern.compile("^(?:-1|-?\\d+)([a-z\\u00b5]+)$");
void check(String s, String setting) {
    Matcher m = TV.matcher(s.toLowerCase(Locale.ROOT).trim());
    if (!m.matches()) throw new IllegalArgumentException("bad " + setting + ": " + s);
    if (!s.equals("-1")) {
        long n = Long.parseLong(m.group(0).replaceAll("[a-z\\u00b5]+$", ""));
        if (n < -1) throw new IllegalArgumentException("negative duration not allowed: " + s);
    }
}

// Narrow string inputs known to be safe for TimeValue
static boolean isAcceptableDuration(String s) {
    if (s == null) return false;
    String n = s.trim().toLowerCase(Locale.ROOT);
    return n.equals("-1") || n.matches("0+") || n.matches("\\d+(ns|us|micros|ms|s|m|h|d)");
}

try {
    TimeValue tv = TimeValue.parseTimeValue(raw, setting);
} catch (IllegalArgumentException e) {
    // surface to the user/config layer with the setting name; do not silently default
    throw new ConfigException("Invalid value for [" + setting + "]: " + raw, e);
}

When it happens

Trigger: Calling TimeValue.parseTimeValue (or any setting parser that delegates to it) with input like "-5s", "-100ms", "-2h", or "-50". Produced when an index setting, cluster setting, or transport timeout is set to a negative number other than -1. Concretely fires at TimeValue.java:416 after Long.parseLong succeeds with value < -1.

Common situations: A user sets a timeout setting (e.g. search.default_search_timeout, transport.connect_timeout) to a negative value by mistake, or a formula/variable that underflows to negative. Copy-pasting a value meant for a different unit. Tooling that injects computed durations without clamping to a minimum.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• failed to parse [{}], fractional time values are not support
• failed to parse [{}]
• failed to parse setting [{}] with value [{}] as a time value
• Failed to parse value [{}] as only [true] or [false] are all
• duration cannot be negative, was given [{}]

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/619003cb59c65fd6. Report an issue: GitHub.