Compliance Operator scans - Compliance Operator | Security and compliance

Running compliance scans
Scheduling the result server pod on a worker node

The ScanSetting and ScanSettingBinding APIs are recommended to run compliance scans with the Compliance Operator. For more information on these API objects, run:

$ oc explain scansettings

$ oc explain scansettingbindings

Running compliance scans

You can run a scan using the Center for Internet Security (CIS) profiles. For convenience, the Compliance Operator creates a ScanSetting object with reasonable defaults on startup. This ScanSetting object is named default.

For all-in-one control plane and worker nodes, the compliance scan runs twice on the worker and control plane nodes. The compliance scan might generate inconsistent scan results. You can avoid inconsistent results by defining only a single role in the ScanSetting object.

Procedure

Inspect the ScanSetting object by running:

$ oc describe scansettings default -n openshift-compliance

Example output

apiVersion: compliance.openshift.io/v1alpha1
kind: ScanSetting
metadata:
  name: default
  namespace: openshift-compliance
rawResultStorage:
  pvAccessModes:
  - ReadWriteOnce (1)
  rotation: 3 (2)
  size: 1Gi (3)
roles:
- worker (4)
- master (4)
scanTolerations: (5)
  default:
  - operator: Exists
  schedule: 0 1 * * * (6)

1	The Compliance Operator creates a persistent volume (PV) that contains the results of the scans. By default, the PV will use access mode `ReadWriteOnce` because the Compliance Operator cannot make any assumptions about the storage classes configured on the cluster. Additionally, `ReadWriteOnce` access mode is available on most clusters. If you need to fetch the scan results, you can do so by using a helper pod, which also binds the volume. Volumes that use the `ReadWriteOnce` access mode can be mounted by only one pod at time, so it is important to remember to delete the helper pods. Otherwise, the Compliance Operator will not be able to reuse the volume for subsequent scans.
2	The Compliance Operator keeps results of three subsequent scans in the volume; older scans are rotated.
3	The Compliance Operator will allocate one GB of storage for the scan results.
4	If the scan setting uses any profiles that scan cluster nodes, scan these node roles.
5	The default scan setting object also scans all the nodes.
6	The default scan setting object runs scans at 01:00 each day.

As an alternative to the default scan setting, you can use default-auto-apply, which has the following settings:

apiVersion: compliance.openshift.io/v1alpha1
kind: ScanSetting
metadata:
  name: default-auto-apply
  namespace: openshift-compliance
autoUpdateRemediations: true (1)
autoApplyRemediations: true (1)
rawResultStorage:
  pvAccessModes:
    - ReadWriteOnce
  rotation: 3
  size: 1Gi
schedule: 0 1 * * *
roles:
  - worker
  - master
scanTolerations:
  default:
  - operator: Exists

1	Setting `autoUpdateRemediations` and `autoApplyRemediations` flags to `true` allows you to easily create `ScanSetting` objects that auto-remediate without extra steps.

Create a ScanSettingBinding object that binds to the default ScanSetting object and scans the cluster using the cis and cis-node profiles. For example:

apiVersion: compliance.openshift.io/v1alpha1
kind: ScanSettingBinding
metadata:
  name: cis-compliance
  namespace: openshift-compliance
profiles:
  - name: ocp4-cis-node
    kind: Profile
    apiGroup: compliance.openshift.io/v1alpha1
  - name: ocp4-cis
    kind: Profile
    apiGroup: compliance.openshift.io/v1alpha1
settingsRef:
  name: default
  kind: ScanSetting
  apiGroup: compliance.openshift.io/v1alpha1

Create the ScanSettingBinding object by running:
```
$ oc create -f <file-name>.yaml -n openshift-compliance
```
At this point in the process, the ScanSettingBinding object is reconciled and based on the Binding and the Bound settings. The Compliance Operator creates a ComplianceSuite object and the associated ComplianceScan objects.
Follow the compliance scan progress by running:
```
$ oc get compliancescan -w -n openshift-compliance
```
The scans progress through the scanning phases and eventually reach the DONE phase when complete. In most cases, the result of the scan is NON-COMPLIANT. You can review the scan results and start applying remediations to make the cluster compliant. See Managing Compliance Operator remediation for more information.

Scheduling the result server pod on a worker node

The result server pod mounts the persistent volume (PV) that stores the raw Asset Reporting Format (ARF) scan results. The nodeSelector and tolerations attributes enable you to configure the location of the result server pod.

This is helpful for those environments where control plane nodes are not permitted to mount persistent volumes.

Procedure

Create a ScanSetting custom resource (CR) for the Compliance Operator:

Define the ScanSetting CR, and save the YAML file, for example, rs-workers.yaml:

apiVersion: compliance.openshift.io/v1alpha1
kind: ScanSetting
metadata:
  name: rs-on-workers
  namespace: openshift-compliance
rawResultStorage:
  nodeSelector:
    node-role.kubernetes.io/worker: "" (1)
  pvAccessModes:
  - ReadWriteOnce
  rotation: 3
  size: 1Gi
  tolerations:
  - operator: Exists (2)
roles:
- worker
- master
scanTolerations:
  - operator: Exists
schedule: 0 1 * * *

1	The Compliance Operator uses this node to store scan results in ARF format.
2	The result server pod tolerates all taints.

To create the ScanSetting CR, run the following command:
```
$ oc create -f rs-workers.yaml
```

Verification

To verify that the ScanSetting object is created, run the following command:

$ oc get scansettings rs-on-workers -n openshift-compliance -o yaml

Example output

apiVersion: compliance.openshift.io/v1alpha1
kind: ScanSetting
metadata:
  creationTimestamp: "2021-11-19T19:36:36Z"
  generation: 1
  name: rs-on-workers
  namespace: openshift-compliance
  resourceVersion: "48305"
  uid: 43fdfc5f-15a7-445a-8bbc-0e4a160cd46e
rawResultStorage:
  nodeSelector:
    node-role.kubernetes.io/worker: ""
  pvAccessModes:
  - ReadWriteOnce
  rotation: 3
  size: 1Gi
  tolerations:
  - operator: Exists
roles:
- worker
- master
scanTolerations:
- operator: Exists
schedule: 0 1 * * *
strictNodeScan: true