Consul

Consul is a distributed service mesh to connect, secure, and configure services across any runtime platform and public or private cloud. If Consul is installed on your environment, the Sysdig agent will automatically connect and collect basic metrics. If the Consul Access Control List (ACL) is configured, you may need to edit the default entries to connect. Also, additional latency metrics can be collected by modifying default entries. See the Default Configuration, below.

Note

It's easy! Sysdig automatically detects metrics from this app based on standard default configurations.

This page describes the default configuration settings, how to edit the configuration to collect additional information, the metrics available for integration, and a sample result in the Sysdig Monitor UI.

Consul Configuration

Consul is ready to expose metrics without any special configuration.

Sysdig Agent Configuration

Review how to Edit dragent.yaml to Integrate or Modify Application Checks.

Default Configuration

By default, Sysdig's dragent.default.yaml uses the following code to connect with Consul and collect basic metrics.

app_checks:
  - name: consul
    pattern:
      comm: consul
    conf:
      url: "http://localhost:8500"
      catalog_checks: yes

With the dragent.default.yaml file, the below set of metrics are available in the Sysdig Monitor UI:

Metrics name

consul.catalog.nodes_critical

consul.catalog.nodes_passing

consul.catalog.nodes_up

consul.catalog.nodes_warning

consul.catalog.total_nodes

consul.catalog.services_critical

consul.catalog.services_passing

consul.catalog.services_up

consul.catalog.services_warning

consul.peers

Additional metrics and event can be collected by adding configuration in dragent.yaml file. The ACL token must be provided if enabled. See the following examples.

Warning

Remember! Never edit dragent.default.yaml directly; always edit only dragent.yaml.

Example 1: Enable Leader Change Event

self_leader_check An enabled node will watch for itself to become the leader and will emit an event when that happens. It can be enabled on all nodes.

app_checks:
  - name: consul
    pattern:
      comm: consul
    conf:
      url: "http://localhost:8500"
      catalog_checks: yes
      self_leader_check: yes
    logs_enabled: true

Example 2: Enable Latency Metrics

If the network_latency_checks flag is enabled, then the Consul network coordinates will be retrieved and the latency calculated for each node and between data centers.

app_checks:
  - name: consul
    pattern:
      comm: consul
    conf:
      url: "http://localhost:8500"
      catalog_checks: yes
      network_latency_checks: yes
    logs_enabled: true

With the above changes, you can see the following additional metrics:

Metrics name

consul.net.node.latency.min

consul.net.node.latency.p25

consul.net.node.latency.median

consul.net.node.latency.p75

consul.net.node.latency.p90

consul.net.node.latency.p95

consul.net.node.latency.p99

consul.net.node.latency.max

Example 3: Enable ACL Token

When the ACL System is enabled in Consul, the ACL Agent Token must be added in dragent.yaml in order to collect metrics.

Follow Consul's official documentation to Configure ACL, Bootstrap ACL and Create Agent Token.

app_checks:
  - name: consul
    pattern:
      comm: consul
    conf:
      url: "http://localhost:8500"
      acl_token: "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" #Add agent token
      catalog_checks: yes
      logs_enabled: true

Example 4: Collect Metrics from Non-Leader Node

Required: Agent 9.6.0+

With agent 9.6.0, you can use the configuration option single_node_install (Optional. Default: false). Set this option to true and the app check will be performed on non-leader nodes of Consul.

app_checks:
   - name: consul
    pattern:
      comm: consul
    conf:
      url: "http://localhost:8500"
      catalog_checks: yes
      single_node_install: true

StatsD Metrics

In addition to the metrics from the Sysdig app-check, there are many other metrics that Consul can send using StatsD. Those metrics will be automatically collected by the Sysdig agent's StatsD integration if Consul is configured to send them.

Add statsd_address under telemetry to the Consul config file. The default config file location is /consul/config/local.json 

{
...
  "telemetry": {
     "statsd_address": "127.0.0.1:8125"
  }
...
}

See Telemetry Metrics for more details.

Metrics Available

See Consul Metrics.

Result in the Monitor UI

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