先試後買

See the Explanation.
Explanation:
1. Access the VM console: virtctl console <vm>
2. Run:
yum install -y fio
fio --name=test --size=1G --rw=randread --bs=4k --iodepth=64 --numjobs=4 --runtime=60
3. Evaluate read/write throughput and IOPS.
4. Test multiple storage classes if needed.
5. Tune disk type for better performance.

See the Explanation.
Explanation:
1. Ensure the storage class supports allowVolumeExpansion.
2. Run:
oc patch pvc vm-root-disk -p '{"spec": {"resources": {"requests": {"storage": "15Gi"}}}}'
3. Restart the VM.
4. Resize partition inside the OS using growpart or resize2fs.
5. Confirm disk size with df -h.

See the Explanation.
Explanation:
1. Create a ClusterIP service for the VM.
2. Define an Ingress object pointing to that service.
3. Example:
rules:
- host:
myapp.example.com
http:
paths:
-
path: /
back
end:
service:
name: vm-
service port:
number: 80
4. Ensure DNS resolves to Ingress controller IP.
5. Test with curl myapp.example.com.

See the Explanation.
Explanation:
1. Create a vm.yaml
file: apiVersion:
kubevirt.io/v1
kind: VirtualMachine
metadata:
name: test-vm
namespace: default
spec:
running: true
template:
spec:
domain:
devices:
disks:
- name: rootdisk
disk:
bus: virtio
resources:
requests:
memory: 1Gi
volumes:
- name:
rootdisk
containerD
isk:
image: quay.io/containerdisks/fedora:latest
2. Apply with: oc apply -f vm.yaml
3. Check status: oc get vm test-vm

See the Explanation.
Explanation:
1. Run: oc delete vmsnapshot <name>
2. If using deletionPolicy: Retain, the volumesnapshotcontents remain.
3. Use snapshots for manual restore.
4. PVCs remain unaffected.
5. You can later recreate snapshot objects if needed.

See the Explanation.
Explanation:
1. Use substitution:
userData: |
#cloud-config
hostname: ${HOSTNAME}
ssh_authorized_keys:
- ${SSH_KEY}
2. Define HOSTNAME and SSH_KEY in template parameters.
3. Use oc process -p to override values.
4. Allows per-VM customization.
5. Great for templated automation.

See the Explanation.
Explanation:
1. Rename disks and PVCs during cloning.
2. Use metadata.name overrides for DV.
3. Avoid using original VM name in disk names.
4. Review cloned VM YAML before applying.
5. Prevents import failures.

See the Explanation.
Explanation:
1. Access the VM.
2. Run:
sudo systemctl enable chronyd
3. Reboot the
VM: sudo
reboot
4. After reboot, verify:
systemctl is-enabled
chronyd
5. Should return enabled.

See the Explanation.
Explanation:
1. Go to Administrator view in the OpenShift Web Console
2. Navigate to Virtualization Overview
3. Check health of subsystems like CDI, HCO, SSP
4. Verify running VMs, templates, alerts
5. View recent events and system metrics

See the Explanation.
Explanation:
1. VM should use masquerade interface (default).
2. Inside VM: ping 8.8.8.8 or curl http://example.com
3. External IP is seen via NAT.
4. Run tcpdump on node interface to confirm NAT.
5. Useful when Multus is not needed.

See the Explanation.
Explanation:
1. Create PVC for the disk.
2. Use:
virtctl addvolume <vm-name> --volume-name hotplug-disk --persist
3. Monitor attachment: oc describe vmi <vm-name>
4. Access inside VM: lsblk, dmesg
5. Detach with virtctl removevolume.

See the Explanation.
Explanation:
1. SSH into the VM or use console.
2. Update repo:
sudo apt update
3. Install package:
sudo apt install -y
curl
4. Confirm
with: curl --
version
5. Successful output indicates installation.

See the Explanation.
Explanation:
1. Export the template:
oc get template <name> -n openshift -o yaml > custom-template.yaml
2. Modify the disk size under dataVolumeTemplates: or PVC size.
3. Change template metadata.name.
4. Apply: oc apply -f custom-template.yaml
5. Use new template for VM creation.