pinpoint-apm/pinpoint · warning

invalid hostGroupName='<hostGroupName>'

Error message

invalid hostGroupName='<hostGroupName>'

What it means

Pinpoint's TelegrafMetricController rejects HTTP requests whose hostGroupName path/query parameter fails isValidGroupName (regex validation). It returns HTTP 400 with the message so telemetry ingestion is refused until a valid group name is supplied.

Source

Thrown at metric-module/metric/src/main/java/com/navercorp/pinpoint/metric/collector/controller/TelegrafMetricController.java:91

        this.tenantProvider = Objects.requireNonNull(tenantProvider, "tenantProvider");
    }


    @PostMapping(value = "/telegraf")
    public ResponseEntity<String> saveSystemMetric(
            @RequestHeader(value = "hostGroupName") String hostGroupName,
            @RequestBody TelegrafMetrics telegrafMetrics, BindingResult bindingResult
    ) throws BindException {
        if (bindingResult.hasErrors()) {
            SimpleErrorMessage simpleErrorMessage = new SimpleErrorMessage(bindingResult);
            logger.warn("metric binding error. header=hostGroupName:{} errorCount:{} {}", hostGroupName, bindingResult.getErrorCount(), simpleErrorMessage);
            throw new BindException(bindingResult);
        }

        if (!isValidGroupName(hostGroupName)) {
            logger.warn("invalid hostGroupName='{}'", hostGroupName);
            return ResponseEntity.badRequest().body("invalid hostGroupName='" + hostGroupName + "'");
        }

        String hostName = getHost(telegrafMetrics);
        if (StringUtils.isEmpty(hostName)) {
            // hostname null check
            logger.info("hostName is empty. hostGroupName={}", hostGroupName);
            return ResponseEntity.badRequest().body("hostName is empty");
        }

        if (!isValidHostName(hostName)) {
            logger.warn("invalid hostName='{}', hostGroupName='{}'", hostName, hostGroupName);
        }

        if (logger.isDebugEnabled()) {
            logger.debug("hostGroupName:{} host:{} size:{}", hostGroupName, hostName, telegrafMetrics.size());
        }

        String tenantId = tenantProvider.getTenantId();

View on GitHub (pinned to 744c3d3075)

Solutions

1. Correct the hostGroupName in the telegraf/client config to match the allowed pattern (alphanumeric, dash, underscore, dot typically)
2. Check the isValidGroupName regex in TelegrafMetricController and conform to it
3. URL-encode the hostGroupName in the request path/query
4. Inspect the 400 response body, which echoes the exact invalid value sent

Example fix

# before (telegraf.conf)
urls = ["http://collector:8080/telegraf/metrics/systemMetric/my group/hosts"]
# after
urls = ["http://collector:8080/telegraf/metrics/systemMetric/my-group/hosts"]

function isValidHostGroupName(name) {
  return typeof name === 'string' && /^[a-zA-Z0-9._-]+$/.test(name);
}
// check before POSTing to the telegraf system-metric endpoint

function isNonEmptyString(v) {
  return typeof v === 'string' && v.length > 0;
}

const res = await fetch(url, { method: 'POST', body });
if (res.status === 400) {
  const msg = await res.text();
  if (msg.startsWith('invalid hostGroupName=')) {
    // fix the group name in config and retry
  }
}

When it happens

Trigger: POSTing telegraf metrics to the system-metric endpoint with a hostGroupName containing characters outside the allowed pattern (spaces, slashes, special characters) or an empty value.

Common situations: Telegraf config or client scripts with unencoded or wrong group names; dashboards configured with a group name renamed on the collector; deployments where the telegraf hostGroupName tag contains hostnames with invalid characters.

Understand the failure class

Background: "Invalid query parameter" / "Failed to parse value of ...": fixing bad query string parameters across APIs — this error's family across 36 libraries.

Related errors

• Resource attribute `service.name` is required to save OTLP m
• hostName is empty
• value
• customMetricName must consist of {GroupName}/{MetricName}/La
• negative tick

AI-assisted analysis of pinpoint-apm/pinpoint@744c3d3075 (2026-09-07). Data as JSON: /api/errors/e400745cf8920839. Report an issue: GitHub.