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Configuration of Big Bang is achieved by overriding default values set in the package or Big Bang using the environment template. The template has a 4 potential locations for setting values: base/secrets.enc.yaml, base/configmap.yaml, <env>/secrets.enc.yaml, and <env>/configmap.yaml. Overrides proceed as follows, with <env>/configmap.yaml having the highest precedence.

graph TD
  pkg[Package values]
  -->bb[Big Bang values]
  -->base-s[`base/secrets.enc.yaml` values]
  -->base-c[`base/configmap.yaml` values]
  -->env-s[`<env>/secrets.enc.yaml` values]
  -->env-c[`<env>/configmap.yaml` values]

In all four cases, Big Bang reads a single key named values.yaml that contains the data to override. See the Big Bang environment template for examples on how to use these files to override values.


Before configuring Big Bang, it is expected that you have already setup:

  • A Kubernetes cluster
  • A SOPS key pair
  • A Git repository to hold your configuration
  • Pull credentials for the Git repository (if not public)
  • An Iron Bank robot account for production, or a non-robot account for testing. Reference Iron Bank authentication for additional details.
  • Certificates specific to your environment (if needed)

Minimum Viable Configuration📜

At a minimum, the following items must be configured for a default Big Bang deployment:

The Big Bang Environment Template has placeholders for all of the above.

Big Bang Globals📜


Hostname is used to override the domain of deployed packages. This allows you to go to the DNS name of a server using the domain. For example, if the domain is, Kiali can be reached at

Key Description Type Default
hostname Domain to use for deployed servers Domain Name


Registry credentials are used to pull images for Big Bang. By default, it points to Iron Bank, but can be modified to use a private registry. These credentials are passed down to all relevant namespaces as an image pull secret.

Key Description Type Default
registry Container registry location Domain Name
username* Container registry username String ”“
password* User’s password String ”“
email User’s email Email ”“

*Credentials should be SOPS encrypted


Flux settings are used to setup the default continuous deployment configuration for Big Bang packages.

Key Description Type Default
interval Polling interval to check for Git or Helm chart updates ##m##s (ex. 5m30s) 2m
install.retries The number of retries that should be attempted on Helm chart installation failures before bailing. int 3
upgrade.retries The number of retries that should be attempted on Helm chart upgrade failures before bailing. int 3
rollback.timeout The time to wait for any individual Kubernetes operation (like Jobs for hooks) during the performance of a Helm rollback action. ##m##s 5m
rollback.cleanupOnFail Allows deletion of new resources created during the Helm rollback action when it fails. Boolean true


Each package (e.g. istio, clusterAuditor) has configuration to control how Big Bang deploys the package

Key Description Type Default
enabled Determines if the package will get deployed or skipped Boolean true (unless its an addon)
git.repo Location of the Git repo holding the package deployment resources URL
git.branch Branch to use for package deployment resources string chart-release or release-vx.x.x
git.commit SHA of specific commit to use in Git for package deployment resources SHA null
git.tag Git tag to use for package deployment resources string null
ingress.gateway Name of Istio Gateway to use for ingress (if supported) string “public”
sso.* Single sign on configuration (if supported)
database.* External database connection configuration (if supported)
objectStorage.* Object storage configuration (if supported)
values Package specific values to configure List of key/values pairs {}
postRenderers See docs/ list []

Flux Resources📜

Big Bang deploys four flux resources that can be customized:

Resource Controls Location
GitRepository Environment Top-level manifest (e.g. dev.yaml, prod.yaml)
Kustomization Environment Top-level manifest (e.g. dev.yaml, prod.yaml)
GitRepository Big Bang Link
HelmRelease Big Bang Link

In addition, each package contains its own GitRepository and HelmRelease resource that can be customized. Look in the Helm chart templates for the these resources.

Settings for any of these resources can be overridden by patching the resource in your environment’s kustomization files. Use Flux’s documentation for GitRepository, HelmRelease, and Kustomization to find settings for these resources. The following are examples of commonly requested custom patches covered in the [bigbang template repo]

  • Updating flux-system component resource usage
  • Example kustomization.yaml
  • This patch could be used to adjust the resources requested by the flux-system/helm-controller resource. A similar patch could be used to adjust the resources required by the other flux components. > NOTE: If flux is under-resourced, occasionally requests can fail in a manner that looks like a network connectivity issue (use with caution)
  • Adding environment variables to flux-system components
  • Example kustomization.yaml
  • This patch could be used to add AWS credential environment variables into the flux-system/kustomize-controller resource to enable SOPS decryption using a KMS key from outside of AWS.
  • Changing the image name / version
  • Example kustomization.yaml
  • This patch could be used to update the tag of the flux-system component image to be deployed.

NOTE: Multiple patches could be applied within a single kustomization.yaml

Big Bang Version📜

In your kustomization.yaml under your environment, here is an example of how to override the version of Big Bang you will use. You can also use a tag or branch if desired.

  - |-
    kind: GitRepository
      name: bigbang
        $patch: replace
        semver: "1.2.x"

Note: You must put the version in two places, once for Kustomize to pull the right configuration base and two for Git Repository to pull the right Helm Chart.

Environment Location📜

In your top-level <env>.yaml Kubernetes manifest, you would place configuration for the location of your environment. Here is an example:

kind: GitRepository
  name: environment-repo
  namespace: bigbang
  interval: 1m
    branch: main
kind: Kustomization
  name: environment
  namespace: bigbang
  interval: 1m
    kind: GitRepository
    name: environment-repo
  path: ./dev
  prune: true
    provider: sops
      name: sops-gpg

Registry Pull Credentials📜

If you have pull credentials for your docker registry, add them to secrets.enc.yaml. Here is an example:

The name of the Secret must be common-bb or environment-bb for Big Bang to read values from it.

apiVersion: v1
kind: Secret
  name: common-bb
  values.yaml: |-
      username: iron-bank-user
      password: iron-bank-password

You will also need to update your kustomization.yaml to merge with the existing secret:

namespace: bigbang
  - secrets.enc.yaml

Package settings📜

Besides the global settings, package settings are defined by the individual packet’s helm charts. You can find these by reviewing the git.registry setting for the package in Big Bang’s default values.yaml.

To modify a non-sensitive package setting, add it to your configmap.yaml. For sensitive information, follow the pattern for setting registry pull credentials. Here we disable twistlock and set gatekeeper’s replicas to 1:

  enabled: false

    replicas: 1

You will also need to merge this file with the existing configmaps in kustomization.yaml.

The name of the ConfigMap must be common or environment for Big Bang to read values from it.

namespace: bigbang
  - name: common
    behavior: merge
      - values.yaml=configmap.yaml

Last update: 2023-10-02 by Christopher O'Connell