Table: kubernetes_replication_controller - Query Kubernetes Replication Controllers using SQL

Kubernetes Replication Controllers are a core component of Kubernetes that ensure a specified number of pod replicas are running at any given time. They are particularly useful for stateless applications where more instances can be easily created or destroyed. Replication Controllers supersede the functionality of Kubernetes Pods by adding life-cycle control, system introspection, and self-healing mechanisms.

Table Usage Guide

The kubernetes_replication_controller table provides insights into Replication Controllers within Kubernetes. As a DevOps engineer, you can explore controller-specific details through this table, including its status, configuration, and specifications. Utilize it to manage and monitor the state of your Kubernetes environment, ensuring the desired number of pod replicas are always running.

Examples

Basic Info

Explore the status of your Kubernetes replication controllers to understand the current state of your system. This can help you assess the number of desired, current, and ready replicas, and determine the age and selector details of each controller.

select
  name,
  namespace,
  replicas as desired,
  status_replicas as current,
  ready_replicas as ready,
  age(current_timestamp, creation_timestamp),
  selector
from
  kubernetes_replication_controller;

select
  name,
  namespace,
  replicas as desired,
  status_replicas as current,
  ready_replicas as ready,
  (julianday('now') - julianday(creation_timestamp)) as age,
  selector
from
  kubernetes_replication_controller;

Get details of containers and image

Explore the intricacies of your Kubernetes replication controllers by identifying the associated containers and images. This enables you to better understand the structure of your deployment, facilitating more effective management and troubleshooting.

select
  name,
  namespace,
  jsonb_agg(container.value -> 'name') as containers,
  jsonb_agg(container.value -> 'image') as images
from
  kubernetes_replication_controller,
  jsonb_array_elements(template -> 'spec' -> 'containers') as container
group by
  name,
  namespace;

select
  name,
  namespace,
  json_group_array(json_extract(container.value, '$.name')) as containers,
  json_group_array(json_extract(container.value, '$.image')) as images
from
  kubernetes_replication_controller,
  json_each(json_extract(template, '$.spec.containers')) as container
group by
  name,
  namespace;

List manifest resources

Explore the Kubernetes replication controllers with a specified path to understand their names, namespaces, and desired replicas. This can help in managing and monitoring the distribution and replication of workloads in a Kubernetes environment.

select
  name,
  namespace,
  replicas as desired,
  selector,
  path
from
  kubernetes_replication_controller
where
  path is not null;

select
  name,
  namespace,
  replicas as desired,
  selector,
  path
from
  kubernetes_replication_controller
where
  path is not null;

Control examples

Schema for kubernetes_replication_controller

Name	Type	Description
_ctx	jsonb	Steampipe context in JSON form, e.g. connection_name.
annotations	jsonb	Annotations is an unstructured key value map stored with a resource that may be set by external tools to store and retrieve arbitrary metadata.
available_replicas	bigint	The number of available replicas (ready for at least minReadySeconds) for this replica set.
conditions	jsonb	Represents the latest available observations of a replication controller's current state.
context_name	text	Kubectl config context name.
creation_timestamp	timestamp with time zone	CreationTimestamp is a timestamp representing the server time when this object was created.
deletion_grace_period_seconds	bigint	Number of seconds allowed for this object to gracefully terminate before it will be removed from the system. Only set when deletionTimestamp is also set.
deletion_timestamp	timestamp with time zone	DeletionTimestamp is RFC 3339 date and time at which this resource will be deleted.
end_line	bigint	The path to the manifest file.
finalizers	jsonb	Must be empty before the object is deleted from the registry. Each entry is an identifier for the responsible component that will remove the entry from the list. If the deletionTimestamp of the object is non-nil, entries in this list can only be removed.
fully_labeled_replicas	bigint	The number of pods that have labels matching the labels of the pod template of the replicaset.
generate_name	text	GenerateName is an optional prefix, used by the server, to generate a unique name ONLY IF the Name field has not been provided.
generation	bigint	A sequence number representing a specific generation of the desired state.
labels	jsonb	Map of string keys and values that can be used to organize and categorize (scope and select) objects. May match selectors of replication controllers and services.
min_ready_seconds	bigint	Minimum number of seconds for which a newly created pod should be ready without any of its container crashing, for it to be considered available. Defaults to 0
name	text	Name of the object. Name must be unique within a namespace.
namespace	text	Namespace defines the space within which each name must be unique.
observed_generation	bigint	Reflects the generation of the most recently observed replication controller.
owner_references	jsonb	List of objects depended by this object. If ALL objects in the list have been deleted, this object will be garbage collected. If this object is managed by a controller, then an entry in this list will point to this controller, with the controller field set to true. There cannot be more than one managing controller.
path	text	The path to the manifest file.
ready_replicas	bigint	The number of ready replicas for this replica set.
replicas	bigint	Replicas is the number of desired replicas. Defaults to 1.
resource_version	text	An opaque value that represents the internal version of this object that can be used by clients to determine when objects have changed.
selector	jsonb	Selector is a label query over pods that should match the replica count. Label keys and values that must match in order to be controlled by this replica set.
selector_query	text	A query string representation of the selector.
source_type	text	The source of the resource. Possible values are: deployed and manifest. If the resource is fetched from the spec file the value will be manifest.
start_line	bigint	The path to the manifest file.
status_replicas	bigint	The most recently oberved number of replicas.
tags	jsonb	A map of tags for the resource. This includes both labels and annotations.
template	jsonb	Template is the object that describes the pod that will be created if insufficient replicas are detected.
title	text	Title of the resource.
uid	text	UID is the unique in time and space value for this object.

Export

This table is available as a standalone Exporter CLI. Steampipe exporters are stand-alone binaries that allow you to extract data using Steampipe plugins without a database.

You can download the tarball for your platform from the Releases page, but it is simplest to install them with the steampipe_export_installer.sh script:

/bin/sh -c "$(curl -fsSL https://steampipe.io/install/export.sh)" -- kubernetes

You can pass the configuration to the command with the --config argument:

steampipe_export_kubernetes --config '<your_config>' kubernetes_replication_controller