Modern systems coming with two type of BIOS options:
1.UEFI specification
2.Legacy.
if you Legacy and deactivate UEFI option you can install redhat simply by having /boot option. If you go with default option UEFI then you have to do installation by creating::
you have to create /boot/efi instead of only /boot.
then after installation you cannot be able to use "fdisk" option any more. because now you are working in GUID partition table (GPT) not in MBR.
which is the newfangled replacement for the tired and inadequate MS-DOS partition table, and why you might want to use it instead of the familiar old MBR. GPT is part of the UEFI specification, and because Linux is a real operating system with modern features you can use GPT with both UEFI and legacy BIOS.
The Globally Unique Identifiers Partition Table is the modern replacement for the antique MS-DOS Master Boot Record (MBR). The MBR was born in the early 1980s for IBM PCs, way back in the thrilling days of ten-megabyte hard disks. The MBR must live on the first 512 bytes of your storage device, and it holds the bootloader and partition table. The bootloader occupies 446 bytes, the partition table uses 64 bytes, and the remaining two bytes store the boot signature. The MBR is limited to four primary partitions, and a single primary partition can hold an extended partition which can then be divided into logical partitions. Linux supports (theoretically) an unlimited number of logical partitions. In the olden days Linux maxed out at 63 IDE partitions and 15 SCSI partitions because the kernel was limited in the total device numbers it could allocate.
The MBR is tiny and inflexible, and has lasted this long thanks to clever hacks to get around its limitations. Logical Block Addressing (LBA) gets around the limitations of its original cylinders, heads, and sectors (CHS) addressing. The traditional hard disk block size of 512 bytes limits partitions to 2TB in size, though more clever hackery supports the new 4096-byte sectors for a maximum 16TB partition size.
GPT: GPT is part of the Unified Extensible Firmware Interface (UEFI) specification, and on Linux you don't need an EFI BIOS to boot from a GPT partition, but can use it with legacy BIOS systems
GPT does not have primary and logical partitions, but just partitions as GParted
TO use "gdisk" for GPT you have to install the "gpt rpm package". https://www.dropbox.com/s/qmkzocja04s9rv7/gdisk-0.8.10-159.1.x86_64.rpm?dl=0 .
so if you use fdisk you will be get an error and if ty to use gdisk you are not able yo use that without gpt package. ashow below
to see the UUID details "#blkid " command has been used.
you can convert MBR partition to GPT in between the installation
inject "CTRL+ALT+F2" during your installation process to go on command line with 'parted' utility.
#parted
(parted) print /dev/sdb
(parted) select /dev/sdb
(parted) mklabel gdt
(parted) yes
print /dev/sdb
quit
then return to installation process with CTRL+ALT+F6
for Disk partition you can use:
Cfdisk is a linux partition editor with an interactive user interface based on ncurses. It can be used to list out the existing partitions as well as create or modify them.
Here is an example of how to use cfdisk to list the partitions
1.UEFI specification
2.Legacy.
if you Legacy and deactivate UEFI option you can install redhat simply by having /boot option. If you go with default option UEFI then you have to do installation by creating::
you have to create /boot/efi instead of only /boot.
then after installation you cannot be able to use "fdisk" option any more. because now you are working in GUID partition table (GPT) not in MBR.
which is the newfangled replacement for the tired and inadequate MS-DOS partition table, and why you might want to use it instead of the familiar old MBR. GPT is part of the UEFI specification, and because Linux is a real operating system with modern features you can use GPT with both UEFI and legacy BIOS.
The Globally Unique Identifiers Partition Table is the modern replacement for the antique MS-DOS Master Boot Record (MBR). The MBR was born in the early 1980s for IBM PCs, way back in the thrilling days of ten-megabyte hard disks. The MBR must live on the first 512 bytes of your storage device, and it holds the bootloader and partition table. The bootloader occupies 446 bytes, the partition table uses 64 bytes, and the remaining two bytes store the boot signature. The MBR is limited to four primary partitions, and a single primary partition can hold an extended partition which can then be divided into logical partitions. Linux supports (theoretically) an unlimited number of logical partitions. In the olden days Linux maxed out at 63 IDE partitions and 15 SCSI partitions because the kernel was limited in the total device numbers it could allocate.
udev
allocates device numbers dynamically, so those limitations are gone.The MBR is tiny and inflexible, and has lasted this long thanks to clever hacks to get around its limitations. Logical Block Addressing (LBA) gets around the limitations of its original cylinders, heads, and sectors (CHS) addressing. The traditional hard disk block size of 512 bytes limits partitions to 2TB in size, though more clever hackery supports the new 4096-byte sectors for a maximum 16TB partition size.
GPT: GPT is part of the Unified Extensible Firmware Interface (UEFI) specification, and on Linux you don't need an EFI BIOS to boot from a GPT partition, but can use it with legacy BIOS systems
GPT does not have primary and logical partitions, but just partitions as GParted
TO use "gdisk" for GPT you have to install the "gpt rpm package". https://www.dropbox.com/s/qmkzocja04s9rv7/gdisk-0.8.10-159.1.x86_64.rpm?dl=0 .
so if you use fdisk you will be get an error and if ty to use gdisk you are not able yo use that without gpt package. ashow below
to see the UUID details "#blkid " command has been used.
you can convert MBR partition to GPT in between the installation
inject "CTRL+ALT+F2" during your installation process to go on command line with 'parted' utility.
#parted
(parted) print /dev/sdb
(parted) select /dev/sdb
(parted) mklabel gdt
(parted) yes
print /dev/sdb
quit
for Disk partition you can use:
Cfdisk is a linux partition editor with an interactive user interface based on ncurses. It can be used to list out the existing partitions as well as create or modify them.
Here is an example of how to use cfdisk to list the partitions