What causes "[http-client] invalid max retry times:{}" in alibaba/nacos?

Set MAINTAINER_CLIENT_MAX_RETRY_TIMES_KEY to a valid integer (e.g. 3).

alibaba/nacos · error · IllegalArgumentException

[http-client] invalid max retry times:{}

Error message

[http-client] invalid max retry times:{}

What it means

Thrown by ParamUtil.initMaxRetryTimes as an IllegalArgumentException when the max-retry configuration value cannot be parsed as an integer. The property key is MAINTAINER_CLIENT_MAX_RETRY_TIMES_KEY, defaulting to DEFAULT_MAX_RETRY_TIMES. Runs at class-load time.

Source

Thrown at maintainer-client/src/main/java/com/alibaba/nacos/maintainer/client/utils/ParamUtil.java:113

        try {
            return Integer.parseInt(readTimeoutStr);
        } catch (NumberFormatException e) {
            final String msg = "[http-client] invalid read timeout:" + readTimeoutStr;
            LOGGER.error("[settings] {}", msg, e);
            throw new IllegalArgumentException(msg, e);
        }
    }
    
    private static int initMaxRetryTimes() {
        String maxRetryTimesStr =
            NacosClientProperties.PROTOTYPE.getProperty(MAINTAINER_CLIENT_MAX_RETRY_TIMES_KEY,
                String.valueOf(DEFAULT_MAX_RETRY_TIMES));
        try {
            return Integer.parseInt(maxRetryTimesStr);
        } catch (NumberFormatException e) {
            final String msg = "[http-client] invalid max retry times:" + maxRetryTimesStr;
            LOGGER.error("[settings] {}", msg, e);
            throw new IllegalArgumentException(msg, e);
        }
    }
    
    private static long initRefreshIntervalMills() {
        String refreshIntervalMillsStr = NacosClientProperties.PROTOTYPE.getProperty(
            MAINTAINER_CLIENT_REFRESH_INTERVAL_MILLS_KEY,
            String.valueOf(DEFAULT_REFRESH_INTERVAL_MILLS));
        try {
            return Long.parseLong(refreshIntervalMillsStr);
        } catch (NumberFormatException e) {
            final String msg =
                "[http-client] invalid auth refresh interval:" + refreshIntervalMillsStr;
            LOGGER.error("[settings] {}", msg, e);
            throw new IllegalArgumentException(msg, e);
        }
    }
    
    public static int getConnectTimeout() {

View on GitHub (pinned to 9b989acdf1)

Solutions

Set MAINTAINER_CLIENT_MAX_RETRY_TIMES_KEY to a valid integer (e.g. 3).
Remove the override to fall back to the default retry count.
Audit all configuration sources for non-numeric values in the retry-times property.

Example fix

# before
-Dnacos.maintainer.client.max.retry.times=5x

# after
-Dnacos.maintainer.client.max.retry.times=5

Defensive patterns

Strategy: validation

Validate before calling

String raw = System.getProperty("nacos.maintainer.client.max.retry.times", "");
if (!raw.isEmpty()) {
    try { Integer.parseInt(raw); } catch (NumberFormatException e) {
    throw new IllegalArgumentException("max.retry.times must be numeric, got: " + raw);
    }
}

Prevention

Specify retry count as a plain integer with no suffix or multiplier.
Validate numeric config properties at bootstrap before the client initializes.
Use the documented default if you do not need a custom retry count.

When it happens

Trigger: Setting the system property or environment variable for MAINTAINER_CLIENT_MAX_RETRY_TIMES_KEY to a non-numeric value. NumberFormatException triggers the logged IllegalArgumentException.

Common situations: Properties file or JVM argument contains a non-numeric retry count (e.g. 'three', '5x'). Templated config with an unresolved variable placeholder. Copy-paste error from documentation.

Related errors

AI-assisted analysis of alibaba/nacos@9b989acdf1 (2026-08-14). Data as JSON: /api/errors/720e5542fcc22a92. Report an issue: GitHub.