Which command initializes a device as a new physical volume for LVM?

• A. vgcreate battlestar /dev/sdb
• B. lvcreate -n data -L 10G battlestar
• C. pvcreate /dev/sdb
• D. pvresize /dev/sdb

Answer: (C)

In LVM, you must first turn a block device into a physical volume before you can use it in a volume group. The command that does this exact initialization is pvcreate on the device. It writes the LVM metadata to the disk, marking it as a physical volume so it can participate in a volume group. After that, you would typically create a volume group with vgcreate using the initialized PV, and then create logical volumes inside that group with lvcreate. The other commands perform different tasks: vgcreate builds a volume group from already-initialized physical volumes; lvcreate makes a logical volume inside an existing volume group; pvresize enlarges or reduces the size of an existing physical volume but does not initialize a brand-new device.