SSH exporter

The SSH exporter attempts to make an SSH connection to a remote system and optionally run a command and test output.

This expecter is intended to query multiple SSH servers from an external host.

The /ssh metrics endpoint exposes SSH metrics and requires the target parameter. The module parameter can also be used to select which configuration module to use, the default module is default.

The /metrics endpoint exposes Go and process metrics for this exporter.

Configuration

The configuration defines modules that are used to configure the SSH client for a given target.

Example:

modules:
  default:
    user: prometheus
    private_key: /home/prometheus/.ssh/id_rsa
    command: uptime
    command_expect: "load average"
    timeout: 5
  password:
    user: prometheus
    password: secret
  certificate:
    user: prometheus
    private_key: /home/prometheus/.ssh/id_ed25519
    certificate: /home/prometheus/.ssh/id_ed25519-cert.pub
  verify:
    user: prometheus
    private_key: /home/prometheus/.ssh/id_rsa
    known_hosts: /etc/ssh/ssh_known_hosts
    host_key_algorithms:
    - ssh-rsa
    command: uptime
    command_expect: "load average"
    timeout: 5
  capture:
    user: prometheus
    private_key: /home/prometheus/.ssh/id_rsa
    command: /some/command/with/output
    output_metric: true
    output_truncate: 50

Example with curl would query host1 with the password module and host2 with the default module.

curl "http://localhost:9312/ssh?target=host1.example.com:22&module=password"
curl http://localhost:9312/ssh?target=host2.example.com:22

Configuration options for each module:

• user - The username for the SSH connection
• password - The password for the SSH connection, required if private_key is not specified
• private_key - The SSH private key for the SSH connection, required if password is not specified
• certificate - The SSH certificate for the private key for the SSH connection
• known_hosts - Optional SSH known hosts file to use to verify hosts
• host_key_algorithms - Optional list of SSH host key algorithms to use
  • See constants beginning with KeyAlgo* in crypto/ssh
• timeout - Optional timeout of the SSH connection, session and optional command.
  • The default comes from the --collector.ssh.default-timeout flag.
• command - Optional command to run.
• command_expect - Optional regular expression of output to expect from the command.
• output_metric - If true the exporter will expose the command output via ssh_output{output="<output here>"} metric.
• output_truncate - Sets the max length for a string in ssh_output metric's output label. Set to -1 to disable truncating.

Docker

Example of running the Docker container

docker run -d -p 9312:9312 -v "ssh_exporter.yaml:/ssh_exporter.yaml:ro" treydock/ssh_exporter

Example of running the Docker container and making SSH private key available. This requires setting private_key value to /.ssh/id_rsa.

docker run -d -p 9312:9312 \
-v "ssh_exporter.yaml:/ssh_exporter.yaml:ro" \
-v "/home/prometheus/.ssh/id_rsa:/.ssh/id_rsa:ro" \
treydock/ssh_exporter

Install

Download the latest release

Add the user that will run ssh_exporter

groupadd -r ssh_exporter
useradd -r -d /var/lib/ssh_exporter -s /sbin/nologin -M -g ssh_exporter -M ssh_exporter

Install compiled binaries after extracting tar.gz from release page.

cp /tmp/ssh_exporter /usr/local/bin/ssh_exporter

Add the necessary config, see configuration section

Add systemd unit file and start service. Modify the ExecStart with desired flags.

cp systemd/ssh_exporter.service /etc/systemd/system/ssh_exporter.service
systemctl daemon-reload
systemctl start ssh_exporter

Build from source

To produce the ssh_exporter binary:

make build

Or

go get github.com/treydock/ssh_exporter

Prometheus configs

The following example assumes this exporter is running on the Prometheus server and communicating to the remote SSH hosts.

- job_name: ssh
  metrics_path: /ssh
  static_configs:
  - targets:
    - host1.example.com:22
    - host2.example.com:22
    labels:
      module: default
  - targets:
    - host3.example.com:22
    - host4.example.com:22
    labels:
      module: verify
  relabel_configs:
  - source_labels: [__address__]
    target_label: __param_target
  - source_labels: [__param_target]
    target_label: instance
  - target_label: __address__
    replacement: 127.0.0.1:9312
  - source_labels: [module]
    target_label: __param_module
  metric_relabel_configs:
  - regex: "^(module)$"
    action: labeldrop
- job_name: ssh-metrics
  metrics_path: /metrics
  static_configs:
  - targets:
    - localhost:9312