HTTP Endpoints

Plugin: go.d.plugin Module: httpcheck

Overview

This collector monitors HTTP servers availability status and response time.

Possible statuses:

Status	Description
success	HTTP request completed successfully with a status code matching the configured status_accepted range (default: 200), and the response body and headers (if configured) match expectations.
timeout	HTTP request timed out before receiving a response (default: 1 second).
no_connection	Failed to establish a connection to the target.
redirect	Received a redirect response (3xx status code) while not_follow_redirects is configured.
bad_status	HTTP request completed with a status code outside the configured status_accepted range (default: non-200).
bad_content	HTTP request completed successfully but the response body does not match the expected content (when using response_match).
bad_header	HTTP request completed successfully but response headers do not match the expected values (when using headers_match).

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 target

The metrics refer to the monitored target.

Labels:

Label	Description
url	url value that is set in the configuration file.

Metrics:

Metric	Dimensions	Unit
httpcheck.response_time	time	ms
httpcheck.response_length	length	characters
httpcheck.status	success, timeout, redirect, no_connection, bad_content, bad_header, bad_status	boolean
httpcheck.in_state	time	boolean

Alerts

The following alerts are available:

Alert name	On metric	Description
httpcheck_web_service_up	httpcheck.status	HTTP check endpoint ${label:url} liveness status
httpcheck_web_service_bad_content	httpcheck.status	Percentage of HTTP responses from ${label:url} with unexpected content in the last 5 minutes
httpcheck_web_service_bad_status	httpcheck.status	Percentage of HTTP responses from ${label:url} with unexpected status in the last 5 minutes
httpcheck_web_service_bad_header	httpcheck.status	Percentage of HTTP responses from ${label:url} with unexpected header in the last 5 minutes
httpcheck_web_service_timeouts	httpcheck.status	Percentage of timed-out HTTP requests to ${label:url} in the last 5 minutes
httpcheck_web_service_no_connection	httpcheck.status	Percentage of failed HTTP requests to ${label:url} in the last 5 minutes

Setup

Prerequisites

No action required.

Configuration

File

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

Options

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

Config options

Name	Description	Default	Required
update_every	Data collection frequency.	5	no
autodetection_retry	Recheck interval in seconds. Zero means no recheck will be scheduled.	0	no
url	Server URL.		yes
status_accepted	HTTP accepted response statuses. Anything else will result in 'bad status' in the status chart.	[200]	no
response_match	If the status code is accepted, the content of the response will be matched against this regular expression.		no
headers_match	This option defines a set of rules that check for specific key-value pairs in the HTTP headers of the response.	[]	no
headers_match.exclude	This option determines whether the rule should check for the presence of the specified key-value pair or the absence of it.	no	no
headers_match.key	The exact name of the HTTP header to check for.		yes
headers_match.value	The pattern to match against the value of the specified header.		no
cookie_file	Path to cookie file. See cookie file format.		no
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.

Config

jobs:
  - name: local
    url: http://127.0.0.1:8080

With HTTP request headers

Configuration with HTTP request headers that will be sent by the client.

Config

jobs:
  - name: local
    url: http://127.0.0.1:8080
    headers:
      Host: localhost:8080
      User-Agent: netdata/go.d.plugin
      Accept: */*

With status_accepted

A basic example configuration with non-default status_accepted.

Config

jobs:
  - name: local
    url: http://127.0.0.1:8080
    status_accepted:
      - 200
      - 204

With header_match

Example configurations with header_match. See the value pattern syntax.

Config

jobs:
    # The "X-Robots-Tag" header must be present in the HTTP response header,
    # but the value of the header does not matter.
    # This config checks for the presence of the header regardless of its value.
  - name: local
    url: http://127.0.0.1:8080
    header_match:
      - key: X-Robots-Tag

    # The "X-Robots-Tag" header must be present in the HTTP response header
    # only if its value is equal to "noindex, nofollow".
    # This config checks both the presence of the header and its value.
  - name: local
    url: http://127.0.0.1:8080
    header_match:
      - key: X-Robots-Tag
        value: '= noindex,nofollow'

    # The "X-Robots-Tag" header must not be present in the HTTP response header
    # but the value of the header does not matter.
    # This config checks for the presence of the header regardless of its value.
  - name: local
    url: http://127.0.0.1:8080
    header_match:
      - key: X-Robots-Tag
        exclude: yes

    # The "X-Robots-Tag" header must not be present in the HTTP response header
    # only if its value is equal to "noindex, nofollow".
    # This config checks both the presence of the header and its value.
  - name: local
    url: http://127.0.0.1:8080
    header_match:
      - key: X-Robots-Tag
        exclude: yes
        value: '= noindex,nofollow'

HTTP authentication

Basic HTTP authentication.

Config

jobs:
  - name: local
    url: http://127.0.0.1:8080
    username: username
    password: password

HTTPS with self-signed certificate

Do not validate server certificate chain and hostname.

Config

jobs:
  - name: local
    url: https://127.0.0.1:8080
    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://127.0.0.1:8080

  - name: remote
    url: http://192.0.2.1:8080

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 httpcheck 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 httpcheck

Getting Logs

If you're encountering problems with the httpcheck 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 httpcheck

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 httpcheck /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 httpcheck