system-and-network-administration-course/week2/lab2-solution.org

#+title: Lab2 Solution
#+title: Amirlan Sharipov (BS21-CS-01)
#+author: Amirlan Sharipov (BS21-CS-01)
#+PROPERTY: header-args :results verbatim :exports both
#+OPTIONS: ^:nil

* Questions 1
** What is fdisk utility used for?
to manipulate disk partition table
** Show the bootable device(s) on your machine, and identify which partition(s) are bootable.
*** Output of fdisk -l:
...
Device         Start       End   Sectors  Size Type
/dev/sdb1       2048     34815     32768   16M Microsoft reserved
/dev/sdb2      34816 524285951 524251136  250G Microsoft basic data
/dev/sdb3  524285952 659988479 135702528 64.7G Linux filesystem
/dev/sdb4  659988480 863920127 203931648 97.2G Linux filesystem
/dev/sdb5  958291968 975173631  16881664    8G Linux swap
/dev/sdb6  975173632 976773134   1599503  781M EFI System
/dev/sdb7  863920128 956194815  92274688   44G Linux filesystem
/dev/sdb8  956194816 958291967   2097152    1G EFI System
*** Answer
/dev/sdb6 and /dev/sdb8 are bootable partitions

** What is logical block address?
is a scheme to index the locations of logical blocks of a device. Starts with LBA 0
** Why did we specify the count, the bs, and the skip options when using dd?
Number of blocks, block size, and how many blocks to skip
** Why does a GPT formatted disk have the MBR?
To maintain compatibility and protect GPT disk and from MBR-based disk utilities.
** Name two differences between primary and logical partitions in an MBR partitioning scheme
There can be only 4 primary partitions in MBR disk, while there can be many logical ones on top of an extended partition. Some operating systems cannot boot from a logical partition.


* Questions 2
** Why is Shim used to load the GRUB bootloader?
To make Secure Boot mechanism work.
** Can you locate your grub configuration file? Show the path.
/boot/grub/grub.cfg
Also, there is /etc/default/grub which can be used to generate a grub config using grub-mkconfig
** According to the boot order, what is the third boot device on your computer? How did you check this?
BootCurrent: 0003
Timeout: 0 seconds
BootOrder: 0003,0004,0009,0001,0002,0000,2001,0006,0005,2002,2003
...
Boot0009* Artix HD(10,GPT,...
It's Artix on my hard drive, accoding to efibootmgr -v

* Questions 3
** How many inodes are in use on your system?
#+begin_src bash
df --output=source,iused
#+end_src

#+RESULTS:
#+begin_example
Filesystem      IUsed
dev               717
run              1314
/dev/sdb3      720461
tmpfs               1
tmpfs              22
/dev/sdb4      677792
/dev/sdb6           0
tmpfs              71
/dev/sda9       16193
/dev/sda8       33171
#+end_example

** What is the filesystem type of the EFI partition?
FAT32
** What device is mounted at your root / directory? Show proof.
#+begin_src bash
lsblk
#+end_src

#+RESULTS:
#+begin_example
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
sda      8:0    0 931.5G  0 disk
...
sdb      8:16   0 465.8G  0 disk
├─sdb1   8:17   0    16M  0 part
├─sdb2   8:18   0   250G  0 part
├─sdb3   8:19   0  64.7G  0 part /
├─sdb4   8:20   0  97.2G  0 part /home
├─sdb5   8:21   0     8G  0 part [SWAP]
├─sdb6   8:22   0   781M  0 part /boot
├─sdb7   8:23   0    44G  0 part
└─sdb8   8:24   0     1G  0 part
#+end_example
/dev/sdb3

** What is your partition UUID?
For PARTUUID:
#+begin_src bash
lsblk -dno PARTUUID /dev/sdb3
#+end_src

#+RESULTS:
: fbef9613-fbf5-8445-8d1c-7a63709d1229

** Show at least two methods of viewing the UUID of a block device.
lsblk -dno UUID /dev/sdb3
blkid

** What is the function of /dev/zero?
Source of zero bytes. Can be used with dd to fill a file with zeros.