apache/cassandra · error · ConfigurationException

Invalid value of auto_snapshot_ttl: ${conf.auto_snapshot_ttl

Error message

Invalid value of auto_snapshot_ttl: ${conf.auto_snapshot_ttl}

What it means

Cassandra validates auto_snapshot_ttl at startup by parsing it into DurationSpec.IntSecondsBound. If the configured string is not a valid duration (wrong format or unit not accepted for seconds-bound), the IllegalArgumentException is rethrown as a ConfigurationException with the offending raw value.

Source

Thrown at src/java/org/apache/cassandra/config/DatabaseDescriptor.java:632

    }

    private static void applySimpleConfig()
    {
        //Doing this first before all other things in case other pieces of config want to construct
        //InetAddressAndPort and get the right defaults
        InetAddressAndPort.initializeDefaultPort(getStoragePort());

        validateUpperBoundStreamingConfig();

        if (conf.auto_snapshot_ttl != null)
        {
            try
            {
                autoSnapshoTtl = new DurationSpec.IntSecondsBound(conf.auto_snapshot_ttl);
            }
            catch (IllegalArgumentException e)
            {
                throw new ConfigurationException("Invalid value of auto_snapshot_ttl: " + conf.auto_snapshot_ttl, false);
            }
        }

        if (conf.commitlog_sync == null)
        {
            throw new ConfigurationException("Missing required directive CommitLogSync", false);
        }

        if (conf.commitlog_sync == CommitLogSync.batch)
        {
            if (conf.commitlog_sync_period.toMilliseconds() != 0)
            {
                throw new ConfigurationException("Batch sync specified, but commitlog_sync_period found.", false);
            }
            logger.debug("Syncing log with batch mode");
        }
        else if (conf.commitlog_sync == CommitLogSync.group)
        {

View on GitHub (pinned to 88fd0f6a0e)

Solutions

Set auto_snapshot_ttl to a valid duration string, e.g. '300s', '5m', or '0' to disable TTL
Verify the unit suffix is one the IntSecondsBound spec accepts (seconds-based)
Check cassandra.yaml syntax: value and unit separated properly, no stray characters

Example fix

# before (cassandra.yaml)
auto_snapshot_ttl: 5hours
# after
auto_snapshot_ttl: 5h

Defensive patterns

Strategy: validation

Validate before calling

if (conf.auto_snapshot_ttl != null && !conf.auto_snapshot_ttl.matches("^\\d+(s|m|h|d)$")) throw new IllegalArgumentException("invalid auto_snapshot_ttl: " + conf.auto_snapshot_ttl);

Try / catch

try { DatabaseDescriptor.daemonInitialization(); } catch (ConfigurationException e) { log.error("auto_snapshot_ttl invalid: {}", e.getMessage()); }

Prevention

Always include a unit suffix (e.g. '300s', '5m')
Use '0' to disable snapshot TTL rather than garbage values
Validate yaml in CI with Cassandra's config parser

When it happens

Trigger: cassandra.yaml contains auto_snapshot_ttl with an invalid value (e.g. 'abc', negative, or a unit unsupported by IntSecondsBound); DatabaseDescriptor.applySimpleConfig (via applyAll or toolInitialization) parses it.

Common situations: Typos like '5 mintues', using a unit not allowed for this spec, hand-edited yaml with missing spaces, or setting it to a negative duration.

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/0995b9cf7a89b9c0. Report an issue: GitHub.