Configuring Crossplane with Argo CD
Argo CD and Crossplane are a great combination. Argo CD provides GitOps while Crossplane turns any Kubernetes cluster into a Universal Control Plane for all your resources. Configuration details are required in order for the two to work together properly. This doc will help you understand these requirements. It's recommended to use Argo CD version 2.4.8 or later with Crossplane.
Argo CD synchronizes Kubernetes resource manifests stored in a Git repository with those running in a Kubernetes cluster (GitOps). Argo CD has different ways to configure how it tracks resources. With Crossplane, you need to configure Argo CD to use Annotation based resource tracking. See the Argo CD docs for additional detail.
Configuring Argo CD with Crossplane
Set Resource Tracking Method
In order for Argo CD to correctly track Application resources that contain Crossplane related objects it needs to be configured to use the annotation mechanism.
To configure it, edit the argocd-cm ConfigMap in the argocd Namespace as such:
apiVersion: v1
kind: ConfigMap
data:
application.resourceTrackingMethod: annotation
Set Health Status
Argo CD has a built-in health assessment for Kubernetes resources. Some checks are supported by the community directly
in Argo's repository. For example the Provider
from pkg.crossplane.io has already been declared which means there no further configuration needed.
Argo CD also enable customising these checks per instance, and that's the mechanism used to provide support of Provider's CRDs.
To configure it, edit the argocd-cm ConfigMap in the argocd Namespace.
ProviderConfig may have no status or a status.users field.
apiVersion: v1
kind: ConfigMap
data:
application.resourceTrackingMethod: annotation
resource.customizations: |
"*.upbound.io/*":
health.lua: |
health_status = {
status = "Progressing",
message = "Provisioning ..."
}
local function contains (table, val)
for i, v in ipairs(table) do
if v == val then
return true
end
end
return false
end
local has_no_status = {
"ProviderConfig",
"ProviderConfigUsage"
}
if obj.status == nil or next(obj.status) == nil and contains(has_no_status, obj.kind) then
health_status.status = "Healthy"
health_status.message = "Resource is up-to-date."
return health_status
end
if obj.status == nil or next(obj.status) == nil or obj.status.conditions == nil then
if obj.kind == "ProviderConfig" and obj.status.users ~= nil then
health_status.status = "Healthy"
health_status.message = "Resource is in use."
return health_status
end
return health_status
end
for i, condition in ipairs(obj.status.conditions) do
if condition.type == "LastAsyncOperation" then
if condition.status == "False" then
health_status.status = "Degraded"
health_status.message = condition.message
return health_status
end
end
if condition.type == "Synced" then
if condition.status == "False" then
health_status.status = "Degraded"
health_status.message = condition.message
return health_status
end
end
if condition.type == "Ready" then
if condition.status == "True" then
health_status.status = "Healthy"
health_status.message = "Resource is up-to-date."
return health_status
end
end
end
return health_status
"*.crossplane.io/*":
health.lua: |
health_status = {
status = "Progressing",
message = "Provisioning ..."
}
local function contains (table, val)
for i, v in ipairs(table) do
if v == val then
return true
end
end
return false
end
local has_no_status = {
"Composition",
"CompositionRevision",
"DeploymentRuntimeConfig",
"ProviderConfig",
"ProviderConfigUsage"
}
if obj.status == nil or next(obj.status) == nil and contains(has_no_status, obj.kind) then
health_status.status = "Healthy"
health_status.message = "Resource is up-to-date."
return health_status
end
if obj.status == nil or next(obj.status) == nil or obj.status.conditions == nil then
if obj.kind == "ProviderConfig" and obj.status.users ~= nil then
health_status.status = "Healthy"
health_status.message = "Resource is in use."
return health_status
end
return health_status
end
for i, condition in ipairs(obj.status.conditions) do
if condition.type == "LastAsyncOperation" then
if condition.status == "False" then
health_status.status = "Degraded"
health_status.message = condition.message
return health_status
end
end
if condition.type == "Synced" then
if condition.status == "False" then
health_status.status = "Degraded"
health_status.message = condition.message
return health_status
end
end
if contains({"Ready", "Healthy", "Offered", "Established"}, condition.type) then
if condition.status == "True" then
health_status.status = "Healthy"
health_status.message = "Resource is up-to-date."
return health_status
end
end
end
return health_status
Set Resource Exclusion
Crossplane providers generates a ProviderConfigUsage for each of the managed resource (MR) it handles. This resource
enable representing the relationship between MR and a ProviderConfig so that the controller can use it as finalizer when a
ProviderConfig is deleted. End users of Crossplane aren't expected to interact with this resource.
Argo CD UI reactivity can be impacted as the number of resource and types grow. To help keep this number low we
recommend hiding all ProviderConfigUsage resources from Argo CD UI.
To configure resource exclusion edit the argocd-cm ConfigMap in the argocd Namespace as such:
apiVersion: v1
kind: ConfigMap
data:
resource.exclusions: |
- apiGroups:
- `apiGroups`:
- "*"
kinds:
- ProviderConfigUsage
The use of "*" as apiGroups will enable the mechanism for all Crossplane Providers.
Increase Kubernetes Client QPS
As the number of CRDs grow on a control plane it will increase the amount of queries Argo CD Application Controller needs to send to the Kubernetes API. If this is the case you can increase the rate limits of the Argo CD Kubernetes client.
Set the environment variable ARGOCD_K8S_CLIENT_QPS to 300 for improved compatibility with a large number of CRDs.
The default value of ARGOCD_K8S_CLIENT_QPS is 50, modifying the value will also update ARGOCD_K8S_CLIENT_BURST as it
is default to ARGOCD_K8S_CLIENT_QPS x 2.