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Hands-on Lab·Linux Foundation Certified System Administrator

Partitions on a device you made

Storage is a fifth of the exam and every task begins with a block device. This guide makes one out of a file, which behaves like a disk in every way that matters and costs nothing - then puts a GPT label and two partitions on it, and explains why the partitions do not show up until you ask for them.

Storage Guide 30 of 38 Intermediate

parted 3.x and util-linux on both families, and the commands are identical. Whether the partition device nodes appear without partprobe is NOT identical, and the last step of this page shows both outcomes. GPT is what you should be creating; MBR appears only on old systems.

Both families. The RHEL transcript came first, during an outage that took both Ubuntu hosts offline; the whole sequence was run again on Ubuntu afterwards, and that second run is the last step of each page - it corrected something the first one had me believing.
Server NameIP AddressOSRolesCPURAMHDD
LFCS-A01192.168.0.70Ubuntu 26.04 LTSPrimary host - most guides run only here2 Core4 GB50 GB
LFCS-C01192.168.0.72AlmaLinux 10.2The other distribution - dnf, firewalld and NetworkManager2 Core4 GB50 GB

This guide includes

Use this to start the storage fifth of the exam. This matters because new partitions are invisible until the kernel re-reads the table - so the device you just created is not there yet.

Before you start

  1. A block device out of a file

  2. A partition table, and two partitions

  3. And why the partitions are not visible yet

  4. The same sequence on Ubuntu, which corrected me

Official sources

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