Hadoop Distributed File System (HDFS)

Plugin: go.d.plugin Module: hfs

Overview

This collector monitors HDFS nodes.

Netdata accesses HDFS metrics over Java Management Extensions (JMX) through the web interface of an HDFS daemon.

This collector is supported on all platforms.

This collector supports collecting metrics from multiple instances of this integration, including remote instances.

Default Behavior

Auto-Detection

This integration doesn't support auto-detection.

Limits

The default configuration for this integration does not impose any limits on data collection.

Performance Impact

The default configuration for this integration is not expected to impose a significant performance impact on the system.

Metrics

Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

Per Hadoop Distributed File System (HDFS) instance

These metrics refer to the entire monitored application.

This scope has no labels.

Metrics:

Metric	Dimensions	Unit	DataNode	NameNode
hdfs.heap_memory	committed, used	MiB	•	•
hdfs.gc_count_total	gc	events/s	•	•
hdfs.gc_time_total	ms	ms	•	•
hdfs.gc_threshold	info, warn	events/s	•	•
hdfs.threads	new, runnable, blocked, waiting, timed_waiting, terminated	num	•	•
hdfs.logs_total	info, error, warn, fatal	logs/s	•	•
hdfs.rpc_bandwidth	received, sent	kilobits/s	•	•
hdfs.rpc_calls	calls	calls/s	•	•
hdfs.open_connections	open	connections	•	•
hdfs.call_queue_length	length	num	•	•
hdfs.avg_queue_time	time	ms	•	•
hdfs.avg_processing_time	time	ms	•	•
hdfs.capacity	remaining, used	KiB		•
hdfs.used_capacity	dfs, non_dfs	KiB		•
hdfs.load	load	load		•
hdfs.volume_failures_total	failures	events/s		•
hdfs.files_total	files	num		•
hdfs.blocks_total	blocks	num		•
hdfs.blocks	corrupt, missing, under_replicated	num		•
hdfs.data_nodes	live, dead, stale	num		•
hdfs.datanode_capacity	remaining, used	KiB	•
hdfs.datanode_used_capacity	dfs, non_dfs	KiB	•
hdfs.datanode_failed_volumes	failed volumes	num	•
hdfs.datanode_bandwidth	reads, writes	KiB/s	•

Alerts

The following alerts are available:

Alert name	On metric	Description
hdfs_capacity_usage	hdfs.capacity	summary datanodes space capacity utilization
hdfs_missing_blocks	hdfs.blocks	number of missing blocks
hdfs_stale_nodes	hdfs.data_nodes	number of datanodes marked stale due to delayed heartbeat
hdfs_dead_nodes	hdfs.data_nodes	number of datanodes which are currently dead
hdfs_num_failed_volumes	hdfs.num_failed_volumes	number of failed volumes

Setup

Prerequisites

No action required.

Configuration

File

The configuration file name for this integration is go.d/hdfs.conf.

The file format is YAML. Generally, the structure is:

update_every: 1
autodetection_retry: 0
jobs:
  - name: some_name1
  - name: some_name1

You can edit the configuration file using the edit-config script from the Netdata config directory.

cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config go.d/hdfs.conf

Options

The following options can be defined globally: update_every, autodetection_retry.

Config options

Name	Description	Default	Required
update_every	Data collection frequency.	1	no
autodetection_retry	Recheck interval in seconds. Zero means no recheck will be scheduled.	0	no
url	Server URL.	http://127.0.0.1:9870/jmx	yes
timeout	HTTP request timeout.	1	no
username	Username for basic HTTP authentication.		no
password	Password for basic HTTP authentication.		no
proxy_url	Proxy URL.		no
proxy_username	Username for proxy basic HTTP authentication.		no
proxy_password	Password for proxy basic HTTP authentication.		no
method	HTTP request method.	GET	no
body	HTTP request body.		no
headers	HTTP request headers.		no
not_follow_redirects	Redirect handling policy. Controls whether the client follows redirects.	no	no
tls_skip_verify	Server certificate chain and hostname validation policy. Controls whether the client performs this check.	no	no
tls_ca	Certification authority that the client uses when verifying the server's certificates.		no
tls_cert	Client TLS certificate.		no
tls_key	Client TLS key.		no

Examples

Basic

A basic example configuration.

jobs:
  - name: local
    url: http://127.0.0.1:9870/jmx

HTTP authentication

Basic HTTP authentication.

Config

jobs:
  - name: local
    url: http://127.0.0.1:9870/jmx
    username: username
    password: password

HTTPS with self-signed certificate

Do not validate server certificate chain and hostname.

Config

jobs:
  - name: local
    url: https://127.0.0.1:9870/jmx
    tls_skip_verify: yes

Multi-instance

Note: When you define multiple jobs, their names must be unique.

Collecting metrics from local and remote instances.

Config

jobs:
  - name: local
    url: http://127.0.0.1:9870/jmx

  - name: remote
    url: http://192.0.2.1:9870/jmx

Troubleshooting

Debug Mode

Important: Debug mode is not supported for data collection jobs created via the UI using the Dyncfg feature.

To troubleshoot issues with the hfs collector, run the go.d.plugin with the debug option enabled. The output should give you clues as to why the collector isn't working.

• Navigate to the plugins.d directory, usually at /usr/libexec/netdata/plugins.d/. If that's not the case on your system, open netdata.conf and look for the plugins setting under [directories].

  cd /usr/libexec/netdata/plugins.d/

• Switch to the netdata user.

  sudo -u netdata -s

• Run the go.d.plugin to debug the collector:

  ./go.d.plugin -d -m hfs

  To debug a specific job:

  ./go.d.plugin -d -m hfs -j jobName

Getting Logs

If you're encountering problems with the hfs collector, follow these steps to retrieve logs and identify potential issues:

• Run the command specific to your system (systemd, non-systemd, or Docker container).
• Examine the output for any warnings or error messages that might indicate issues. These messages should provide clues about the root cause of the problem.

System with systemd

Use the following command to view logs generated since the last Netdata service restart:

journalctl _SYSTEMD_INVOCATION_ID="$(systemctl show --value --property=InvocationID netdata)" --namespace=netdata --grep hfs

System without systemd

Locate the collector log file, typically at /var/log/netdata/collector.log, and use grep to filter for collector's name:

grep hfs /var/log/netdata/collector.log

Note: This method shows logs from all restarts. Focus on the latest entries for troubleshooting current issues.

Docker Container

If your Netdata runs in a Docker container named "netdata" (replace if different), use this command:

docker logs netdata 2>&1 | grep hfs