louislam/uptime-kuma · error · Error

Interval cannot be less than ${MIN_INTERVAL_SECOND} seconds

Error message

Interval cannot be less than ${MIN_INTERVAL_SECOND} seconds

What it means

validate() rejects monitor.interval below MIN_INTERVAL_SECOND (currently 1). validate() runs on addMonitor (server.js:787) and editMonitor (server.js:964) via the socket API, so the error surfaces at monitor save time.

Source

Thrown at server/model/monitor.js:1627

            }
        }

        const parent = await Monitor.getParent(monitorID);
        if (parent != null) {
            return await Monitor.isUnderMaintenance(parent.id);
        }

        return false;
    }

    /**
     * Validate monitor configuration
     * @returns {void}
     * @throws {Error} If validation fails
     */
    validate() {
        if (this.interval < MIN_INTERVAL_SECOND) {
            throw new Error(`Interval cannot be less than ${MIN_INTERVAL_SECOND} seconds`);
        }

        if (this.retryInterval < MIN_INTERVAL_SECOND) {
            throw new Error(`Retry interval cannot be less than ${MIN_INTERVAL_SECOND} seconds`);
        }

        if (this.response_max_length !== undefined) {
            if (this.response_max_length < 0) {
                throw new Error(`Response max length cannot be less than 0`);
            }

            if (this.response_max_length > RESPONSE_BODY_LENGTH_MAX) {
                throw new Error(`Response max length cannot be more than ${RESPONSE_BODY_LENGTH_MAX} bytes`);
            }
        }

        // Validate JSON fields to prevent invalid JSON from being stored in database
        if (this.kafkaProducerBrokers) {

View on GitHub (pinned to 6b5ea01557)

Solutions

1. Set interval to at least MIN_INTERVAL_SECOND (1s); in practice prefer >=20s to avoid hammering targets
2. If importing from a fork with different limits, clamp values to >=1 before import

Example fix

// before
monitor.interval = 0;

// after
monitor.interval = 20;

const MIN_INTERVAL_SECOND = 1;
if (monitor.interval < MIN_INTERVAL_SECOND) throw new Error(`interval must be >= ${MIN_INTERVAL_SECOND}`);

function isValidInterval(v) { return Number.isFinite(v) && v >= 1; }

// validate() throws on addMonitor/editMonitor; wrap the socket call
try { await socket.emit("addMonitor", payload); } catch (e) { /* surface e.message */ }

When it happens

Trigger: Calling addMonitor/editMonitor with interval set to 0, a negative number, or otherwise below 1 second.

Common situations: Script/API creating a monitor with an invalid interval; importing a backup from a fork that permitted sub-second intervals; UI race producing an empty value.

Related errors

• Retry interval cannot be less than ${MIN_INTERVAL_SECOND} se
• Response max length cannot be less than 0
• Response max length cannot be more than ${RESPONSE_BODY_LENG
• Kafka Producer Brokers must be valid JSON: ${e.message}
• Kafka Producer SASL Options must be valid JSON: ${e.message}

AI-assisted analysis of louislam/uptime-kuma@6b5ea01557 (2026-08-12). Data as JSON: /api/errors/0ec33f02ea923bea. Report an issue: GitHub.