> ## Documentation Index
> Fetch the complete documentation index at: https://cloudanix.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Create Administrative Boundaries Between Resources Using Namespaces

### More Info:

Namespaces provide administrative and security boundaries for segregating cluster resources. Objects should be organized into dedicated namespaces rather than sharing a single namespace.

### Risk Level

Low

### Address

Security

### Compliance Standards

* CIS GKE

### Triage and Remediation

<Tabs>
  <Tab title="Remediation">
    ### Remediation

    <AccordionGroup>
      <Accordion title="Manual Steps" defaultOpen="true">
        1. **Inventory current namespaces and workloads**\
           Run on any machine with kubectl access:
           ```bash theme={null}
           kubectl get namespaces
           kubectl get all --all-namespaces
           ```
           Review which namespaces exist, which are system/managed (e.g., `kube-system`, `gke-system`, `istio-system`, `gatekeeper-system`), and where your application workloads currently run.

        2. **Identify workloads running in inappropriate or shared namespaces**\
           Focus on `default`, `kube-system`, and any “catch‑all” namespaces:
           ```bash theme={null}
           kubectl get all -n default
           kubectl get all -n kube-system
           ```
           Decide which applications, environments (dev/test/prod), or teams are mixed together and should be separated (e.g., multiple apps sharing `default`, non-system apps in `kube-system`).

        3. **Design a namespace structure aligned to admin and security boundaries**\
           On a planning machine (no commands):
           * Define namespaces per application, per environment, or per tenant/team (e.g., `app1-prod`, `app1-dev`, `payments-prod`, `analytics-dev`).
           * Decide which namespaces require stronger controls (e.g., separate namespace for internet-facing workloads, sensitive data, or admin tooling).\
             Document the desired namespace layout and which workloads should live where.

        4. **Create or update namespace definitions**\
           Run on any machine with kubectl access:
           * To create missing namespaces:
             ```bash theme={null}
             kubectl create namespace app1-prod
             kubectl create namespace app1-dev
             ```
           * Or define them declaratively in a manifest file (example):
             ```yaml theme={null}
             apiVersion: v1
             kind: Namespace
             metadata:
               name: app1-prod
             ---
             apiVersion: v1
             kind: Namespace
             metadata:
               name: app1-dev
             ```
             Apply with:
             ```bash theme={null}
             kubectl apply -f namespaces.yaml
             ```

        5. **Relocate workloads into the appropriate namespaces**\
           For each workload that should move (Deployments, Services, Jobs, etc.):
           * Export its manifest and edit the `metadata.namespace` (and any namespace-qualified references such as ConfigMaps, Secrets, ServiceAccounts):
             ```bash theme={null}
             kubectl get deploy my-app -n default -o yaml > my-app.yaml
             ```
             Edit `my-app.yaml` to set:
             ```yaml theme={null}
             metadata:
               namespace: app1-prod
             ```
           * Delete the old object and recreate it in the new namespace (ensure you understand the downtime impact):
             ```bash theme={null}
             kubectl delete deploy my-app -n default
             kubectl apply -f my-app.yaml
             ```
           Repeat for Services, ConfigMaps, Secrets, etc., ensuring all required dependencies exist in the target namespace.

        6. **Verify namespace boundaries are in place**\
           Run on any machine with kubectl access:
           ```bash theme={null}
           kubectl get namespaces
           kubectl get all -n app1-prod
           kubectl get all -n app1-dev
           kubectl get all -n default
           ```
           Confirm that:
           * Application workloads are no longer concentrated in `default` or mixed with system components.
           * Workloads are organized according to the designed boundaries (per app/environment/team) and system namespaces contain only system components.
      </Accordion>

      <Accordion title="Using kubectl">
        ```bash theme={null}
        # 1) List all namespaces and their age
        # Run on: any machine with kubectl access
        kubectl get namespaces --show-labels
        ```

        Review guidance:

        * Potential problems if:
          * Almost all workloads are in `default`, `kube-system`, or `kube-public`.
          * Many namespaces exist but have no clear purpose or labels (e.g., missing `env=`, `team=`, `app=` style labels).
          * System namespaces (`kube-system`, `kube-public`, `kube-node-lease`, `gke-*`) are used for custom application workloads.

        ```bash theme={null}
        # 2) See which namespaces actually contain workloads
        kubectl get all --all-namespaces
        ```

        Review guidance:

        * Potential problems if:
          * Most `Deployment`, `StatefulSet`, `DaemonSet`, `Job`, or `Pod` objects are in a single shared namespace like `default`.
          * Unrelated applications or teams share the same namespace with no separation.

        ```bash theme={null}
        # 3) Summarize workload kinds per namespace
        kubectl get pods,deploy,sts,ds,job,cronjob -A \
          -o custom-columns='NAMESPACE:.metadata.namespace,KIND:.kind,NAME:.metadata.name' \
          | sort -u
        ```

        Review guidance:

        * Potential problems if:
          * You see many unrelated applications (by name) co-located in the same namespace.
          * There is no visible pattern (e.g., per-team, per-environment, or per-application grouping).

        ```bash theme={null}
        # 4) Inspect labels/annotations on a specific busy namespace (example: default)
        kubectl describe namespace default
        ```

        Review guidance:

        * Potential problems if:
          * The namespace lacks labels that indicate ownership, environment, or purpose.
          * The namespace mixes “shared” or “misc” workloads with no clear boundary.

        ```bash theme={null}
        # 5) Identify which namespaces are used for user workloads vs system
        kubectl get ns \
          -o custom-columns='NAME:.metadata.name,AGE:.metadata.creationTimestamp,LABELS:.metadata.labels'
        ```

        Review guidance:

        * Potential problems if:
          * User workloads appear in system namespaces (names beginning with `kube-` or `gke-`).
          * There is no clear distinction between system and application namespaces.

        ```bash theme={null}
        # 6) For one or two key namespaces, list owners via labels
        # Replace <namespace> as needed
        kubectl get deploy,sts,ds,svc,ingress -n <namespace> \
          -o custom-columns='KIND:.kind,NAME:.metadata.name,TEAM:.metadata.labels.team,APP:.metadata.labels.app,ENV:.metadata.labels.env'
        ```

        Review guidance:

        * Potential problems if:
          * Multiple teams (`TEAM` label) or environments (`ENV` label) share the same namespace.
          * No labels are present to show who owns resources or what boundary they belong to.

        Interpreting issues for this control:

        * You likely fail the intent of CISGKE 4.6.1 if:
          * Most or all application workloads run in `default`.
          * Different applications, teams, or environments are not separated into distinct namespaces.
          * System and application workloads are mixed in the same namespaces.
        * A healthy pattern usually shows:
          * Dedicated namespaces per application, team, or environment.
          * System namespaces used only for system components.
      </Accordion>

      <Accordion title="Automation">
        ```bash theme={null}
        #!/usr/bin/env bash
        # Report namespace usage and potential issues for CIS GKE 4.6.1
        # Run on: any machine with kubectl access and appropriate RBAC

        set -euo pipefail

        echo "=== Cluster-wide Namespace Overview ==="
        kubectl get namespaces -o wide

        echo
        echo "=== Namespace Annotations & Labels (for admin boundaries) ==="
        kubectl get ns -o json \
          | jq -r '
            .items[]
            | {
                name: .metadata.name,
                labels: .metadata.labels,
                annotations: .metadata.annotations
              }' \
          | jq .

        echo
        echo "=== Workloads per Namespace (pods, deployments, statefulsets, daemonsets, jobs, cronjobs) ==="
        # Summarize main workload objects per namespace
        kubectl get ns -o jsonpath='{range .items[*]}{.metadata.name}{"\n"}{end}' \
          | while read -r ns; do
              echo "--- Namespace: ${ns} ---"
              kubectl get pods,deployments,statefulsets,daemonsets,jobs,cronjobs -n "${ns}" --ignore-not-found
              echo
            done

        echo
        echo "=== Namespaces with Mixed 'types' of Workloads (heuristic) ==="
        echo "Note: This heuristic flags namespaces that mix system, infra, and app workloads by label patterns."
        echo "You must manually review and decide if separation is required."

        # Heuristic: classify workloads by label keys commonly used to denote ownership/type
        kubectl get pods --all-namespaces -o json \
          | jq -r '
            .items[]
            | {
                ns: .metadata.namespace,
                name: .metadata.name,
                labels: (.metadata.labels // {}),
                owner: (
                  if .metadata.labels["app.kubernetes.io/part-of"] then "app"
                  elif .metadata.labels["k8s-app"] then "system-or-infra"
                  elif .metadata.labels["app"] then "app"
                  else "unknown"
                  end
                )
              }' \
          | jq -s '
            group_by(.ns)
            | map({
                namespace: .[0].ns,
                counts: (group_by(.owner) | map({(.[0].owner): length}) | add)
              })' \
          | jq -r '
            .[]
            | select((.counts["app"] != null and .counts["system-or-infra"] != null) or (.counts["unknown"] != null and (.counts["app"] != null or .counts["system-or-infra"] != null)))
            '

        echo
        echo "=== Namespaces with Both System and Application-Looking Objects (by name pattern) ==="
        echo "Patterns used: kube-*, istio-*, linkerd, logging, monitoring, prometheus, envoy, ingress"
        echo "Review these for possible separation of system/infra from application workloads."

        patterns='kube-|istio-|linkerd|logging|monitoring|prometheus|envoy|ingress'

        kubectl get pods --all-namespaces -o wide \
          | awk 'NR==1 {next} {print $1, $2}' \
          | while read -r ns pod; do
              if [[ "${pod}" =~ ${patterns} ]]; then
                echo "${ns} SYSTEM_OR_INFRA_POD ${pod}"
              else
                echo "${ns} APP_OR_OTHER_POD ${pod}"
              fi
            done \
          | awk '
              {
                ns=$1; type=$2
                has[ns][type]=1
              }
              END {
                for (n in has) {
                  if (has[n]["SYSTEM_OR_INFRA_POD"] && has[n]["APP_OR_OTHER_POD"]) {
                    print n ": has both system/infra-looking and app-looking pods"
                  }
                }
              }' \
          | sort

        echo
        echo "=== Namespaces with No Clear Labeling for Ownership/Boundary (candidates for review) ==="
        kubectl get ns -o json \
          | jq -r '
            .items[]
            | {
                name: .metadata.name,
                labels: .metadata.labels
              }
            | select(.name != "kube-system" and .name != "kube-public" and .name != "kube-node-lease" and .name != "default")
            | select(
                (.labels["team"] == null)
                and (.labels["owner"] == null)
                and (.labels["app.kubernetes.io/part-of"] == null)
                and (.labels["environment"] == null)
              )
            | .name' \
          | sort

        echo
        echo "=== Objects in the 'default' Namespace (strong candidates for re-namespacing) ==="
        echo "These commonly indicate missing administrative boundaries."
        kubectl get all -n default --show-kind --ignore-not-found

        echo
        echo "=== Summary & Interpretation Guidance ==="
        cat <<'EOF'
        Review guidance (CIS GKE 4.6.1 - MANUAL):

        Potential problems you should investigate:

        1) Heavy use of the 'default' namespace:
           - If many applications, services, or jobs are in 'default', they likely lack
             clear administrative boundaries. Consider moving them into dedicated
             namespaces per app, team, environment, or trust level.

        2) Namespaces that mix system/infra and application workloads:
           - The sections "Namespaces with Mixed 'types' of Workloads" and
             "Namespaces with Both System and Application-Looking Objects" list
             namespaces that appear to host both:
               * cluster/system/infra components (e.g., kube-*, istio-*, logging/monitoring)
               * regular application pods
           - Consider separating system/infra components from business applications
             into distinct namespaces.

        3) Namespaces with no ownership/boundary labels:
           - The "Namespaces with No Clear Labeling" section lists namespaces
             that lack common labels to denote owner, team, or environment.
           - While not a hard failure, unclear ownership often correlates with
             weak administrative boundaries.

        4) General organization:
           - Review whether you have a namespace strategy (e.g. by team, by app,
             by environment: dev/stage/prod, by sensitivity).
           - For each multi-tenant/shared cluster, ensure tenants do not share
             namespaces unless intentionally designed.

        This script only reports; it does NOT change any resources.
        You must decide, per finding, whether to create new namespaces and
        move workloads, following your operational and security requirements.
        EOF
        ```

        **What output indicates a problem (to be manually reviewed):**

        * Many user workloads listed under `=== Objects in the 'default' Namespace ===`.
        * Namespaces listed under:
          * `=== Namespaces with Mixed 'types' of Workloads (heuristic) ===`
          * `=== Namespaces with Both System and Application-Looking Objects ===`
        * Namespaces listed under `=== Namespaces with No Clear Labeling for Ownership/Boundary ===` in a multi-tenant or complex environment.
      </Accordion>
    </AccordionGroup>
  </Tab>
</Tabs>