consul – Add, modify & delete services within a consul cluster

New in version 2.0.

Synopsis

  • Registers services and checks for an agent with a consul cluster. A service is some process running on the agent node that should be advertised by consul’s discovery mechanism. It may optionally supply a check definition, a periodic service test to notify the consul cluster of service’s health.

  • Checks may also be registered per node e.g. disk usage, or cpu usage and notify the health of the entire node to the cluster. Service level checks do not require a check name or id as these are derived by Consul from the Service name and id respectively by appending ‘service:’ Node level checks require a check_name and optionally a check_id.

  • Currently, there is no complete way to retrieve the script, interval or ttl metadata for a registered check. Without this metadata it is not possible to tell if the data supplied with ansible represents a change to a check. As a result this does not attempt to determine changes and will always report a changed occurred. An api method is planned to supply this metadata so at that stage change management will be added.

  • See http://consul.io for more details.

Requirements

The below requirements are needed on the host that executes this module.

  • python >= 2.6

  • python-consul

  • requests

Parameters

Parameter Choices/Defaults Comments
check_id
-
an ID for the service check, defaults to the check name, ignored if part of a service definition.
check_name
-
a name for the service check, defaults to the check id. required if standalone, ignored if part of service definition.
host
-
Default:
"localhost"
host of the consul agent defaults to localhost
http
-
added in 2.0
checks can be registered with an http endpoint. This means that consul will check that the http endpoint returns a successful http status. Interval must also be provided with this option.
interval
-
the interval at which the service check will be run. This is a number with a s or m suffix to signify the units of seconds or minutes e.g 15s or 1m. If no suffix is supplied, m will be used by default e.g. 1 will be 1m. Required if the script param is specified.
notes
-
Notes to attach to check when registering it.
port
-
Default:
8500
the port on which the consul agent is running
scheme
-
added in 2.1
 Default:
"http"
the protocol scheme on which the consul agent is running
script
-
the script/command that will be run periodically to check the health of the service. Scripts require an interval and vise versa
service_address
-
added in 2.1
the address to advertise that the service will be listening on. This value will be passed as the Address parameter to Consul's /v1/agent/service/register API method, so refer to the Consul API documentation for further details.
service_id
-
Default:
"service_name if supplied"
the ID for the service, must be unique per node, defaults to the service name if the service name is supplied
service_name
-
Unique name for the service on a node, must be unique per node, required if registering a service. May be omitted if registering a node level check
service_port
-
the port on which the service is listening. Can optionally be supplied for registration of a service, i.e. if service_name or service_id is set
state
- / required
    Choices:
  • present
  • absent
register or deregister the consul service, defaults to present
tags
-
a list of tags that will be attached to the service registration.
timeout
-
added in 2.0
A custom HTTP check timeout. The consul default is 10 seconds. Similar to the interval this is a number with a s or m suffix to signify the units of seconds or minutes, e.g. 15s or 1m.
token
-
the token key indentifying an ACL rule set. May be required to register services.
ttl
-
checks can be registered with a ttl instead of a script and interval this means that the service will check in with the agent before the ttl expires. If it doesn't the check will be considered failed. Required if registering a check and the script an interval are missing Similar to the interval this is a number with a s or m suffix to signify the units of seconds or minutes e.g 15s or 1m. If no suffix is supplied, m will be used by default e.g. 1 will be 1m
validate_certs
boolean
added in 2.1
    Choices:
  • no
  • yes ←
whether to verify the tls certificate of the consul agent

Examples

- name: register nginx service with the local consul agent
  consul:
    service_name: nginx
    service_port: 80

- name: register nginx service with curl check
  consul:
    service_name: nginx
    service_port: 80
    script: curl http://localhost
    interval: 60s

- name: register nginx with an http check
  consul:
    service_name: nginx
    service_port: 80
    interval: 60s
    http: http://localhost:80/status

- name: register external service nginx available at 10.1.5.23
  consul:
    service_name: nginx
    service_port: 80
    service_address: 10.1.5.23

- name: register nginx with some service tags
  consul:
    service_name: nginx
    service_port: 80
    tags:
      - prod
      - webservers

- name: remove nginx service
  consul:
    service_name: nginx
    state: absent

- name: register celery worker service
  consul:
    service_name: celery-worker
    tags:
      - prod
      - worker

- name: create a node level check to test disk usage
  consul:
    check_name: Disk usage
    check_id: disk_usage
    script: /opt/disk_usage.py
    interval: 5m

- name: register an http check against a service that's already registered
  consul:
    check_name: nginx-check2
    check_id: nginx-check2
    service_id: nginx
    interval: 60s
    http: http://localhost:80/morestatus

Status

Authors

  • Steve Gargan (@sgargan)

Hint

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