Google ACE Practice Question: Order the steps to attach a persistent disk to a…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  Attach the disk to the instance, SSH into the instance, format the disk (if needed), then mount the disk.

  Why this is correct

  Attaching the persistent disk first is required because the VM's operating system only sees the disk as a block device after the attachment completes. Once attached, you SSH in and run `lsblk` or `fdisk -l` to identify the device, then format it with a filesystem such as ext4 if the disk is new. Finally, you mount the formatted filesystem to a mount point like `/mnt/data` so it becomes usable. This sequence ensures the disk is both present and properly initialized before mounting.

• ✗

  Format the disk, attach the disk to the instance, SSH into the instance, then mount the disk.

  Why it's wrong here

  You cannot format a persistent disk that has not been attached to an instance because formatting operates on a block device node—such as `/dev/sdb`—which does not exist until the disk is attached and the guest OS scans the new device. GCP persistent disks are not standalone objects you can format from the Cloud Console; they are network-attached block devices reachable only from an attached VM. Therefore, the attach step must always precede any filesystem creation. After attaching, you SSH in to format, not before.

• ✗

  SSH into the instance, attach the disk, format the disk, then mount the disk.

  Why it's wrong here

  This is incorrect because attaching the disk after SSH does not make the disk available until the attach command completes. However, the main issue is that you should attach before SSH in the sense that attach is a prerequisite; but technically you can SSH first, then attach, but the disk won't be visible until after attach. The order is misleading because format and mount require the disk to be attached, so attach must come before them, but SSH can be done earlier. Common best practice is to attach first to ensure the device is available when you SSH.

• ✗

  Attach the disk, SSH into the instance, mount the disk, then format the disk.

  Why it's wrong here

  Mounting expects the underlying device to already contain a valid filesystem; if you try to mount an unformatted disk, the kernel returns an error such as `mount: /mnt/data: wrong fs type` because no filesystem signature is present. The `mkfs` command creates the filesystem structure, and only after that can `mount` associate the device with a directory. So the mount-before-format ordering is fundamentally broken. SSH placement is irrelevant here; the critical defect is that you omit the required formatting step before mount.

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