Beyond the platform-agnostic install-config.yaml
properties, the installer supports additional, GCP-specific properties.
projectID
(required string): The project where the cluster should be created.region
(required string): The GCP region where the cluster should be created.network
(optional string): The name of an existing GCP VPC where the cluster infrastructure should be provisioned.controlPlaneSubnet
(optional string): The name of an existing GCP subnet which should be used by the cluster control plane.computeSubnet
(optional string): The name of an existing GCP subnet which should be used by the cluster nodes.defaultMachinePlatform
(optional object): Default GCP-specific machine pool properties which apply to machine pools that do not define their own GCP-specific properties.
type
(optional string): The GCP machine type.zones
(optional array of strings): The availability zones used for machines in the pool.
The installer can use an existing VPC and subnets when provisioning an OpenShift cluster. If one of network
, controlPlaneSubnet
, or computeSubnet
is specified, all must be specified (see example below). Furthermore, each of the networks must belong to the project specified by projectID
, and the subnets must belong to the specified cluster region
. The installer will use these existing networks when creating infrastructure such as VM instances, load balancers, firewall rules, and DNS zones.
In a scenario where multiple clusters are installed to the same VPC network, the installer maintains cluster isolation by using firewall rules which specify allowed sources and destinations through network tags. By tagging each Compute Engine VM instance with a unique cluster id and creating corresponding firewall rules, the installer ensures that a cluster's control plane is only accessible by its own member nodes.
By design, possible inter-cluster access is limited to:
- The API, which is globally available with an external publishing strategy or available throughout the network in an internal publishing strategy
- Debugging tools; i.e. ports on VM instances are open to the
machineCidr
for SSH & ICMP
Some example install-config.yaml
are shown below.
For examples of platform-agnostic configuration fragments, see here.
An example minimal GCP install config is:
apiVersion: v1
baseDomain: example.com
metadata:
name: example-cluster
platform:
gcp:
project: example-project
region: us-east1
pullSecret: '{"auths": ...}'
sshKey: ssh-ed25519 AAAA...
An example GCP install config with custom machine pools:
apiVersion: v1
baseDomain: example.com
compute:
- name: worker
platform:
gcp:
type: n2-standard-2
zones:
- us-central1-a
- us-central1-c
replicas: 3
controlPlane:
name: master
platform:
gcp:
type: n2-standard-4
zones:
- us-central1-a
- us-central1-c
replicas: 3
metadata:
name: example-cluster
platform:
gcp:
projectID: openshift-dev-installer
region: us-central1
pullSecret: '{"auths": ...}'
sshKey: ssh-ed25519 AAAA...
An example GCP install config utilizing an existing network and subnets:
apiVersion: v1
baseDomain: example.com
metadata:
name: example-cluster
platform:
gcp:
projectID: example-project
region: us-east1
computeSubnet: example-worker-subnet
controlPlaneSubnet: example-controlplane-subnet
network: example-network
pullSecret: '{"auths": ...}'
sshKey: ssh-ed25519 AAAA...