16 KiB
layout | page_title | sidebar_current | description |
---|---|---|---|
docs | Cloud Auto-join | docs-agent-cloud-auto-join | Consul supports automatic cluster joining using cloud metadata on various providers. |
Cloud Auto-joining
As of Consul 0.9.1, retry-join
accepts a unified interface using the
go-discover library for doing
automatic cluster joining using cloud metadata. To use retry-join with a
supported cloud provider, specify the configuration on the command line or
configuration file as a key=value key=value ...
string.
In Consul 0.9.1-0.9.3 the values need to be URL encoded but for most
practical purposes you need to replace spaces with +
signs.
As of Consul 1.0 the values are taken literally and must not be URL encoded. If the values contain spaces, equals, backslashes or double quotes then they need to be double quoted and the usual escaping rules apply.
$ consul agent -retry-join 'provider=my-cloud config=val config2="some other val" ...'
or via a configuration file:
{
"retry_join": ["provider=my-cloud config=val config2=\"some other val\" ..."]
}
The cloud provider-specific configurations are detailed below. This can be combined with static IP or DNS addresses or even multiple configurations for different providers.
In order to use discovery behind a proxy, you will need to set
HTTP_PROXY
, HTTPS_PROXY
and NO_PROXY
environment variables per
Golang net/http
library.
The following sections give the options specific to each supported cloud provider.
Amazon EC2
This returns the first private IP address of all servers in the given
region which have the given tag_key
and tag_value
.
$ consul agent -retry-join "provider=aws tag_key=... tag_value=..."
{
"retry_join": ["provider=aws tag_key=... tag_value=..."]
}
provider
(required) - the name of the provider ("aws" in this case).tag_key
(required) - the key of the tag to auto-join on.tag_value
(required) - the value of the tag to auto-join on.region
(optional) - the AWS region to authenticate in.addr_type
(optional) - the type of address to discover:private_v4
,public_v4
,public_v6
. Default isprivate_v4
. (>= 1.0)access_key_id
(optional) - the AWS access key for authentication (see below for more information about authenticating).secret_access_key
(optional) - the AWS secret access key for authentication (see below for more information about authenticating).
Authentication & Precedence
- Static credentials
access_key_id=... secret_access_key=...
- Environment variables (
AWS_ACCESS_KEY_ID
andAWS_SECRET_ACCESS_KEY
) - Shared credentials file (
~/.aws/credentials
or the path specified byAWS_SHARED_CREDENTIALS_FILE
) - ECS task role metadata (container-specific).
- EC2 instance role metadata.
The only required IAM permission is ec2:DescribeInstances
, and it is
recommended that you make a dedicated key used only for auto-joining. If the
region is omitted it will be discovered through the local instance's EC2
metadata
endpoint.
Microsoft Azure
This returns the first private IP address of all servers in the given region
which have the given tag_key
and tag_value
in the tenant and subscription, or in
the given resource_group
of a vm_scale_set
for Virtual Machine Scale Sets.
$ consul agent -retry-join "provider=azure tag_name=... tag_value=... tenant_id=... client_id=... subscription_id=... secret_access_key=..."
{
"retry_join": ["provider=azure tag_name=... tag_value=... tenant_id=... client_id=... subscription_id=... secret_access_key=..."]
}
provider
(required) - the name of the provider ("azure" in this case).tenant_id
(required) - the tenant to join machines in.client_id
(required) - the client to authenticate with.secret_access_key
(required) - the secret client key. NOTE This value often may have an equals sign in it's value, especially if generated from the Azure Portal, so is important to wrap in single quotes eg.secret_access_key='fpOfcHQJAQBczjAxiVpeyLmX1M0M0KPBST+GU2GvEN4='
Variables can also be provided by environmental variables:
ARM_SUBSCRIPTION_ID
for subscriptionARM_TENANT_ID
for tenantARM_CLIENT_ID
for clientARM_CLIENT_SECRET
for secret access key
Use these configuration parameters when using tags:
tag_name
- the name of the tag to auto-join on.tag_value
- the value of the tag to auto-join on.
Use these configuration parameters (instead of tag_name
and tag_value
) when using Virtual Machine Scale Sets (Consul 1.0.3 and later):
resource_group
- the name of the resource group to filter on.vm_scale_set
- the name of the virtual machine scale set to filter on.
When using tags the only permission needed is Microsoft.Network/networkInterfaces
.
When using Virtual Machine Scale Sets the only role action needed is Microsoft.Compute/virtualMachineScaleSets/*/read
.
~> Note: If the Consul cluster is hosted on Azure, Consul can use Managed Service Identities (MSI) to access Azure instead of an environment variable and shared client id and secret. MSI must be enabled on the VMs hosting Consul, and it is the preferred configuration since MSI prevents your Azure credentials from being stored in Consul configuration. This feature is supported from Consul 1.7 and above.
Google Compute Engine
This returns the first private IP address of all servers in the given
project which have the given tag_value
.
$ consul agent -retry-join "provider=gce project_name=... tag_value=..."
{
"retry_join": ["provider=gce project_name=... tag_value=..."]
}
provider
(required) - the name of the provider ("gce" in this case).tag_value
(required) - the value of the tag to auto-join on.project_name
(optional) - the name of the project to auto-join on. Discovered if not set.zone_pattern
(optional) - the list of zones can be restricted through an RE2 compatible regular expression. If omitted, servers in all zones are returned.credentials_file
(optional) - the credentials file for authentication. Note, if you set-config-dir
do not store the credentials.json file in the configuration directory as it will be parsed as a config file and Consul will fail to start. See below for more information.
Authentication & Precedence
Discovery requires a GCE Service Account. Credentials are searched using the following paths, in order of precedence.
- Use credentials from
credentials_file
, if provided. - Use JSON file from
GOOGLE_APPLICATION_CREDENTIALS
environment variable. - Use JSON file in a location known to the gcloud command-line tool.
- On Windows, this is
%APPDATA%/gcloud/application_default_credentials.json
. - On other systems,
$HOME/.config/gcloud/application_default_credentials.json
.
- On Windows, this is
- On Google Compute Engine, use credentials from the metadata server. In this final case any provided scopes are ignored.
IBM SoftLayer
This returns the first private IP address of all servers for the given
datacenter with the given tag_value
.
$ consul agent -retry-join "provider=softlayer datacenter=... tag_value=... username=... api_key=..."
{
"retry_join": ["provider=softlayer datacenter=... tag_value=... username=... api_key=..."]
}
provider
(required) - the name of the provider ("softlayer" in this case).datacenter
(required) - the name of the datacenter to auto-join in.tag_value
(required) - the value of the tag to auto-join on.username
(required) - the username to use for auth.api_key
(required) - the api key to use for auth.
Aliyun (Alibaba Cloud)
This returns the first private IP address of all servers for the given
region
with the given tag_key
and tag_value
.
$ consul agent -retry-join "provider=aliyun region=... tag_key=consul tag_value=... access_key_id=... access_key_secret=..."
{
"retry_join": ["provider=aliyun region=... tag_key=consul tag_value=... access_key_id=... access_key_secret=..."]
}
provider
(required) - the name of the provider ("aliyun" in this case).region
(required) - the name of the region.tag_key
(required) - the key of the tag to auto-join on.tag_value
(required) - the value of the tag to auto-join on.access_key_id
(required) -the access key to use for auth.access_key_secret
(required) - the secret key to use for auth.
The required RAM permission is ecs:DescribeInstances
.
It is recommended you make a dedicated key used only for auto-joining.
Digital Ocean
This returns the first private IP address of all servers for the given
region
with the given tag_name
.
$ consul agent -retry-join "provider=digitalocean region=... tag_name=... api_token=..."
{
"retry_join": ["provider=digitalocean region=... tag_name=... api_token=..."]
}
provider
(required) - the name of the provider ("digitalocean" in this case).region
(required) - the name of the region.tag_name
(required) - the value of the tag to auto-join on.api_token
(required) -the token to use for auth.
Openstack
This returns the first private IP address of all servers for the given
region
with the given tag_key
and tag_value
.
$ consul agent -retry-join "provider=os tag_key=consul tag_value=server username=... password=... auth_url=..."
{
"retry_join": ["provider=os tag_key=consul tag_value=server username=... password=... auth_url=..."]
}
provider
(required) - the name of the provider ("os" in this case).tag_key
(required) - the key of the tag to auto-join on.tag_value
(required) - the value of the tag to auto-join on.domain_name
(optional) - the name of the domain.domain_id
(optional) - the id of the domain.project_id
(optional) - the id of the project (tenant id).region
(optional) - the name of the region.user_name
(optional) - the username to use for auth.password
(optional) - the password to use for auth.token
(optional) - the token to use for auth.auth_url
(optional) - the identity endpoint to use for auth.insecure
(optional) - indicates whether the API certificate should not be checked. Any value meanstrue
.
The configuration can also be provided by environment variables.
Scaleway
This returns the first private IP address of all servers for the given
region
with the given tag_name
.
$ consul agent -retry-join "provider=scaleway organization=my-org tag_name=consul-server token=... region=..."
{
"retry_join": ["provider=scaleway organization=my-org tag_name=consul-server token=... region=..."]
}
provider
(required) - the name of the provider ("scaleway" in this case).region
(required) - the name of the region.tag_name
(required) - the name of the tag to auto-join on.organization
(required) - the organization access key to use for auth (equal to access key).token
(required) - the token to use for auth.
TencentCloud
This returns the first IP address of all servers for the given region
with the given tag_key
and tag_value
.
$ consul agent -retry-join "provider=tencentcloud region=... tag_key=consul tag_value=... access_key_id=... access_key_secret=..."
{
"retry_join": ["provider=tencentcloud region=... tag_key=consul tag_value=... access_key_id=... access_key_secret=..."]
}
provider
(required) - the name of the provider ("tencentcloud" in this case).region
(required) - The TencentCloud region.tag_key
(required) - The tag key to auto-join on.tag_value
(required) - The tag value to auto-join on.address_type
(optional) - "private_v4" or "public_v4", default is "private_v4".access_key_id
(required) - The secret id of TencentCloud.access_key_secret
(required) - The secret key of TencentCloud.
This required permission to 'cvm:DescribeInstances'. It is recommended you make a dedicated key used only for auto-joining.
Joyent Triton
This returns the first PrimaryIP addresses for all servers with the given tag_key
and tag_value
.
$ consul agent -retry-join "provider=triton account=testaccount url=https://us-sw-1.api.joyentcloud.com key_id=... tag_key=consul-role tag_value=server"
{
"retry_join": ["provider=triton account=testaccount url=https://us-sw-1.api.joyentcloud.com key_id=... tag_key=consul-role tag_value=server"]
}
provider
(required) - the name of the provider ("triton" in this case).account
(required) - the name of the account.url
(required) - the URL of the Triton api endpoint to use.key_id
(required) - the key id to use.tag_key
(optional) - the instance tag key to use.tag_value
(optional) - the tag value to use.
vSphere
This returns the first private IP address of all servers for the given region with the given tag_name
and category_name
.
$ consul agent -retry-join "provider=vsphere category_name=consul-role tag_name=consul-server host=... user=... password=... insecure_ssl=[true|false]"
{
"retry-join": ["provider=vsphere category_name=consul-role tag_name=consul-server host=... user=... password=... insecure_ssl=[true|false]"]
}
provider
(required) - the name of the provider ("vsphere" is the provider here)tag_name
(required) - The name of the tag to look up.category_name
(required) - The category of the tag to look up.host
(required) - The host of the vSphere server to connect to.user
(required) - The username to connect as.password
(required) - The password of the user to connect to vSphere as.insecure_ssl
(optional) - Whether or not to skip SSL certificate validation.timeout
(optional) - Discovery context timeout (default: 10m)
Packet
This returns the first private IP address (or the IP address of address type
) of all servers with the given project
and auth_token
.
$ consul agent -retry-join "provider=packet auth_token=token project=uuid url=... address_type=..."
{
"retry-join": ["provider=packet auth_token=token project=uuid url=... address_type=..."]
}
provider
(required) - the name of the provider ("packet" is the provider here)project
(required) - the UUID of packet projectauth_token
(required) - the authentication token for packeturl
(optional) - a REST URL for packetaddress_type
(optional) - the type of address to check for in this provider ("private_v4", "public_v4" or "public_v6". Defaults to "private_v4")
Kubernetes (k8s)
The Kubernetes provider finds the IP addresses of pods with the matching label or field selector. This is useful for non-Kubernetes agents that are joining a server cluster running within Kubernetes.
The pod IP is used by default, which requires that the agent connecting can
network to the pod IP. The host_network
boolean can be set to true to use
the host IP instead, but this requires the agent ports (Gossip, RPC, etc.)
to be exported to the host as well.
By default, no port is specified. This causes Consul to use the default
gossip port (default behavior with all join requests). The pod may specify
the consul.hashicorp.com/auto-join-port
annotation to set the port. The value
may be an integer or a named port.
$ consul agent -retry-join "provider=k8s label_selector=\"app=consul,component=server\""
{
"retry-join": ["provider=k8s label_selector=..."]
}
provider
(required) - the name of the provider ("k8s" is the provider here)kubeconfig
(optional) - path to the kubeconfig file. If this isn't set, then in-cluster auth will be attempted. If that fails, the default kubeconfig paths are tried ($HOME/.kube/config
).namespace
(optional) - the namespace to search for pods. If this isn't set, it defaults to all namespaces.label_selector
(optional) - the label selector for matching pods.field_selector
(optional) - the field selector for matching pods.
The Kubernetes token used by the provider needs to have permissions to list pods in the desired namespace.