Chapter 14 - Managing Storage Flashcards
What is MBR?
It is the Master Boot Record partitioning Scheme. It is a system used to define hard disk layout.
what is the boot procedure?
While booting a computer, the Basic Input Output System (BIOS) was loaded to access hardware devices. From the BIOS, the bootable disk device was read, and on this bootable device, the MBR was allocated. The MBR contains all that is needed to start a computer, including a boot loader and a partition table.
What is the default sector size?
512 bytes
How many partitions could be created in the MBR?
Four
What is GPT?
It is a Partitioning scheme introduced for very big storage devices, eg 2TiB or more than this.
GUID Partition Table - GPT
What is the difference between megabyte and a mebibyte?
a megabyte is a multiple of 1,000, and a mebibyte is a multiple of 1,024
What are the different partitioning utilities in RHEL8?
fdisk, gdisk and parted
fdisk is used to create MBR partitions
gdisk is used to create GPT partitions
Which directory or file do you see the kernal partition table?
cat /proc/partitions
Which command to see the non-kernel partition table?
fdisk -l /dev/sda
What command to use to write the changes to kernel partition table?
partprobe /dev/sda
Assuming the partitioning changes were done on /dev/sda
What are the 8 steps to create a MBR partition with fdisk utility?
- Open a root shell and run the fdisk command with the name of the device disk as argument. eg fdisk /dev/sda
- Check how much disk space you have available. Press p to see an overview of current disk allocation. In particular look for the total number of sectors and the last sector that is currently used. If the last partition does not end on the last sector, you have available space to create a new partition.
- Type n to add a new partition and press p to create a primary partition.
- Specify the first sector on disk that the new partition will start on, The first available sector is suggested by default
- Specify the last sector that the partition will end on. By default, the last sector available on disk is suggested.
- define the partition type. By default, a Linux partition type is used.
- If you are happy with the modifications, press w to write them to disk and exit fdisk.
- Type partprobe /dev/sda to write the changes to the kernel partition table
How many primary partitions can you create on a MBR and what to do if you need beyond that?
Four primary partitions. Beyond that you need to create extended partitions
What are the different partition types in GPT?
8200: Linux swap
8300: Linux file system
8e00: Linux LVM
Notice that these are the same partition types as the ones that are used in MBR,
with two 0s added to the IDs. You can also just press Enter to accept the default
partition type 8300.
which command to use to format a partition with a supported file system?
mkfs command using the -t option to specify which filesystem to use
Which command to format partition with XFS file system?
mkfs -t xfs
Which command is a generic tool for managing Ext4 file system properties?
tune2fs
Example: tune2fs -l /dev/sda3
what does tune2fs command do?
It is filesystem properties management command. It shos different fule system properties
What is a label in the filesystem properties?
Labels are used to set a unique name for a file system
Which filesystem management command to use to set a label on the filesystem?
tune2fs -L
Which command is a generic tool for managing XFS file system properties?
xfs_admin
Example : xfs_admin -L mylabel
to set the file system label to mylabel
How is a swap partition or swap memory useful in Linux?
Using swap on Linux is a convenient way to improve Linux kernel memory usage. If a shortage of physical RAM occurs, non-recently used memory pages can be moved to swap, which makes more RAM available for programs that need access to memory
pages.
What is mounting a filesystem?
By mounting a partition (or better, the file system on it), you make its contents accessible through a specific directory.
Which command is used to manually mount and remove mount of a file system?
mount and umount
Example: mount /dev/sda5 /mnt
umount /dev/sda5 /mnt or umount /mnt
Which command to use to get an overview of the current file systems on your system and the UUID that is used by that file system?
blkid
How to automate the file system mounting?
Using the /etc/fstab file
