最も有効な EX380 試験参考書

正解：

See the solution below in Explanation:
Explanation:
* Confirm resources and PVCs exist
* oc -n orders get all
* oc -n orders get pvc
* Ensures there is something meaningful to back up.
* Create backup including volume snapshots
* velero backup create orders-full --include-namespaces orders --snapshot-volumes
* Captures Kubernetes objects and requests PV snapshots where supported.
* Check status/details
* velero backup describe orders-full --details
* velero backup logs orders-full
* Review warnings/errors and confirm snapshot actions.

正解：

See the solution below in Explanation:
Explanation:
Step 1: Identify the application namespace after restore.
The lab shows the namespace as my-app-namespace.
Step 2: Run the SCC assignment command:
oc adm policy add-scc-to-user anyuid -z default -n my-app-namespace
Step 3: Confirm the role binding is applied.
The lab output shows:
clusterrole.rbac.authorization.k8s.io/system:openshift:scc:anyuid added: "default" Detailed explanation:
After a restore, the application may fail if its pods require a security context not permitted by the default SCC allocation. This command grants the anyuid SCC to the default service account in the my-app-namespace project. The -z default syntax targets the default service account, which many restored workloads use if no custom service account is defined. The anyuid SCC allows containers to run with arbitrary user IDs, which some legacy or prebuilt images require. In OpenShift, SCC mismatches commonly cause pods to remain in pending or crash-related states. Assigning the proper SCC resolves those admission issues so workloads can start successfully. This step is therefore a post-restore operational fix to align security policy with application requirements.

正解：

See the solution below in Explanation:
Explanation:
* Collect Keycloak details
* Issuer URL (realm), client ID, and client secret.
* Confirm Keycloak client has correct redirect URI for OpenShift OAuth callback.
* Create a secret with the OIDC client secret
* oc -n openshift-config create secret generic keycloak-oidc-secret \
* --from-literal=clientSecret=' < SECRET > '
* OAuth reads the OIDC client secret from this secret.
* Edit OAuth and add OpenID provider
* oc edit oauth cluster
Add under spec.identityProviders:
- name: keycloak
mappingMethod: claim
type: OpenID
openID:
issuer: "https://keycloak.example.com/realms/ocp"
clientID: "openshift"
clientSecret:
name: keycloak-oidc-secret
claims:
preferredUsername: ["preferred_username"]
name: ["name"]
email: ["email"]
* issuer must match Keycloak realm issuer URL.
* claims determines which token claims map to OpenShift username/name/email.
* Restart OAuth pods
* oc -n openshift-authentication delete pod -l app=oauth-openshift
* Verify by logging in through the web console
* You should be redirected to Keycloak, authenticate, then return to OpenShift.
* Confirm users/identities:
* oc get users
* oc get identities

正解：

See the solution below in Explanation:
Explanation:
Step 1: Make sure the MachineConfig YAML has already been created or modified in the local Git repository.
This Task assumes the file change is ready to be committed.
Step 2: Run the command:
git commit -am "Add MachineConfig for motd" & & git push origin main
Step 3: Verify the commit succeeds and the push goes to the main branch.
The lab output shows:
[main 8d32a1] Add MachineConfig for motd
Detailed explanation:
This Task is part of a GitOps workflow. Instead of manually applying changes directly to the cluster, the desired configuration is stored in Git, and a GitOps controller such as Argo CD synchronizes the cluster to match the repository state. The command commits all tracked modified files with the message Add MachineConfig for motd and then pushes the change to the main branch. In this model, Git becomes the source of truth. A MachineConfig is typically used to manage node-level operating system configuration in OpenShift, so pushing it through GitOps ensures the change is auditable, repeatable, and reconciled declaratively. If the commit does not include the intended YAML, the synchronization mechanism will not apply the desired change.

正解：

See the solution below in Explanation:
Explanation:
Step 1: Ensure the certificate file rhds_ca.crt is available in your current working directory or use the correct path.
The Task requires creating a configmap from this CA certificate file.
Step 2: Run the command:
oc create configmap rhds-ca-config-map --from-file ca.crt=rhds_ca.crt -n openshift-config Step 3: Confirm the configmap is created.
The lab output shows:
configmap/rhds-ca-config-map created
Detailed explanation:
This creates a configmap named rhds-ca-config-map in the openshift-config namespace and maps the local file rhds_ca.crt to the key name ca.crt inside the configmap. This is important in external identity integration because OpenShift may need to trust a custom certificate authority when communicating with LDAP or another secured external service. By placing the certificate in a configmap, the authentication operator or related cluster configuration can reference it cleanly. The key name matters because many OpenShift resources expect a CA bundle key with a specific filename-like convention. If the file path is wrong, the command fails immediately. If the configmap name or key mapping is wrong, the authentication provider referencing it may not trust the external endpoint.