Exam XK0-005 topic 1 question 65 discussion

Changed yet again, but i'm serious this time. IT's C!!

I think I'm going with D here. Label can always change whereas blkid (yes a command) but retrieves the UUID and the UUID are unique to each filesystem.

It's clear it's either C or D.... The best option is to mount to UUID which blkid would display, that's how you figure out the UUID, therefor I think that's why you you mount it to bklid....but it's entirely how you interpret the question for which answer you come up with.

D blkid: This command displays block device information, including a unique identifier called the block device ID. This ID remains constant for a specific disk regardless of device name assignment.

To resolve the device mismatch issue and mount the disk correctly, the administrator should mount the disk using its UUID (Universally Unique Identifier). UUIDs are unique to each filesystem and do not change even if the device name (e.g., /dev/sdb, /dev/sdc) changes, making them ideal for consistent identification of disks. C. mount disk by-label: Disk labels can be useful but are not as unique and reliable as UUIDs. If labels are not unique, they can cause conflicts.

C. By lable. Why? (A) There is no "device-id." (B) The 'fsck' command repairs file systems. (D) The 'blkid' command shows block device attributes. (The sane choice is UUID because the UUID is embedded in the file system of the block device, but that's not an option to choose.)

Option D, mount disk by-blkid, is generally better than option C, mount disk by-label, for a few reasons: Uniqueness: The block ID (blkid) is a unique identifier for each block device, which is guaranteed to be the same across reboots and even if the disk is moved to a different machine. On the other hand, disk labels are not guaranteed to be unique and can be changed by the user, leading to potential conflicts. Presence: Not all filesystems support labels, and even when they do, labels are not always set by default. This means that you might not be able to mount a disk by label if the label has not been set. In contrast, all block devices have a blkid. Consistency: The blkid remains consistent even if the device name (e.g., /dev/sda, /dev/sdb) changes due to hardware changes or reconfiguration. Disk labels do not have this issue, but combined with the points above, using blkid is generally more reliable. Therefore, while both methods can be used to mount a disk, using the blkid (option D) is typically more reliable and less prone to errors or conflicts.

See comment below. Can someone present a clearer argument on why block ID would be correct and not mount disk by-label?

I am going with mount disk by-label because the question states that the IDs were from a clone and the UUIDs are tied to the source device of the cloning. Since the UUIDs of the source of the clone are unique to just that source device and mean nothing to anything else, it would make sense to use the more generic mount disk by-label method. So, C would be the answer.

The "mount disk by-blkid" option allows the administrator to mount the disk using a unique identifier (the block ID) instead of the device name. This is particularly useful when cloning a server and the device names have changed, as it helps to ensure that the correct disk is being mounted. The "mount disk by device-id" option is not correct because it does not exist in the standard Linux mount command. The "fsck -A" option is used to check and repair file systems, but it does not mount the disk. The "mount disk by-label" option is also incorrect as it mounts the disk based on the disk label, but if the disk label has changed as a result of the clone, this option will not work.

Here ya' go: https://unix.stackexchange.com/questions/644708/how-can-i-prevent-disk-uuid-mismatch-when-cloning-a-machine

I changed by vote to A - Device ID is better, Ref: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/managing_file_systems/assembly_overview-of-persistent-naming-attributes_managing-file-systems

According to this link the answer should be C: https://unix.stackexchange.com/questions/644708/how-can-i-prevent-disk-uuid-mismatch-when-cloning-a-machine