X.509 certificate

Plugin: go.d.plugin Module: x509check

Overview

This collectors monitors x509 certificates expiration time and revocation status.

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.

Setup

You can configure the x509check collector in two ways:

Method	Best for	How to
UI	Fast setup without editing files	Go to Nodes → Configure this node → Collectors → Jobs, search for x509check, then click + to add a job.
File	If you prefer configuring via file, or need to automate deployments (e.g., with Ansible)	Edit `go.d/x509check.conf` and add a job.

:::important

UI configuration requires paid Netdata Cloud plan.

:::

Prerequisites

No action required.

Configuration

Options

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

Group	Option	Description	Default	Required
Collection	update_every	Data collection interval (seconds).	1	no
	autodetection_retry	Autodetection retry interval (seconds). Set 0 to disable.	0	no
Target	source	Certificate source. Allowed schemes: https, tcp, tcp4, tcp6, udp, udp4, udp6, file, smtp.		no
	timeout	SSL connection timeout (seconds).	2	no
Validation	check_full_chain	Monitor expiration time for all certificates in the chain (including intermediates and root).	no	no
	check_revocation_status	Check the revocation status of the certificate.	no	no
TLS	tls_skip_verify	Skip TLS certificate and hostname verification (insecure).	no	no
	tls_ca	Path to CA bundle used to validate the server certificate.		no
	tls_cert	Path to client TLS certificate (for mTLS).		no
	tls_key	Path to client TLS private key (for mTLS).		no
Virtual Node	vnode	Associates this data collection job with a Virtual Node.		no

via UI

Configure the x509check collector from the Netdata web interface:

Go to Nodes.
Select the node where you want the x509check data-collection job to run and click the :gear: (Configure this node). That node will run the data collection.
The Collectors → Jobs view opens by default.
In the Search box, type x509check (or scroll the list) to locate the x509check collector.
Click the + next to the x509check collector to add a new job.
Fill in the job fields, then click Test to verify the configuration and Submit to save.
- Test runs the job with the provided settings and shows whether data can be collected.
- If it fails, an error message appears with details (for example, connection refused, timeout, or command execution errors), so you can adjust and retest.

via File

The configuration file name for this integration is go.d/x509check.conf.

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

update_every: 1
autodetection_retry: 0
jobs:
  - name: some_name1
  - name: some_name2

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/x509check.conf

Examples

Website certificate

Website certificate.

jobs:
  - name: my_site_cert
    source: https://my_site.org:443

Local file certificate

Local file certificate.

jobs:
  - name: my_file_cert
    source: file:///home/me/cert.pem

SMTP certificate

SMTP certificate.

jobs:
  - name: my_smtp_cert
    source: smtp://smtp.my_mail.org:587

Multi-instance

Note: When you define more than one job, their names must be unique.

Check the expiration status of the multiple websites' certificates.

jobs:
  - name: my_site_cert1
    source: https://my_site1.org:443

  - name: my_site_cert2
    source: https://my_site1.org:443

  - name: my_site_cert3
    source: https://my_site3.org:443

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 source

These metrics refer to the SSL certificate.

Labels:

Label	Description
source	Same as the “source” configuration option.
common_name	The common name (CN) extracted from the certificate.
depth	The depth of the certificate within the certificate chain. The leaf certificate has a depth of 0, and subsequent certificates (intermediate certificates) have increasing depth values. The root certificate is at the highest depth.

Metrics:

Metric	Dimensions	Unit
x509check.time_until_expiration	expiry	seconds
x509check.revocation_status	not_revoked, revoked	boolean

Alerts

The following alerts are available:

Alert name	On metric	Description
x509check_days_until_expiration	x509check.time_until_expiration	SSL cert expiring soon (${label:source} cn:${label:common_name})
x509check_revocation_status	x509check.revocation_status	SSL cert revoked (${label:source})

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 x509check 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 x509check

To debug a specific job:

./go.d.plugin -d -m x509check -j jobName

Getting Logs

If you’re encountering problems with the x509check 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 x509check

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 x509check /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 x509check

Industry

Technology

Use cases