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                       Personal operating system

PEROPESIS LINUX OS USER MANUAL

This webpage contains information on how to use Peropesis Linux operating system. Although this manual is for both, content and submission purposes not completely finished, but in some aspects it is already may be useful for future or existing users of this system. If you have questions, notes or suggestions about the information in this manual you can write to e-mail: info(at)peropesis.org.

1. Introduction
1.1 What is Linux
2. Booting
2.1 Save an ISO image of the Peropesis live operating system to a USB drive in Microsoft Windows environment
2.2 Save an ISO image of the Peropesis live operating system to a USB drive in Linux environment
2.2.1 Save an ISO image by using the dd program available through the Shell interpreter
2.2.2 Save an ISO image by using the Startup Disk Creator program available through the graphical environment
2.3 Peropesis live OS booting from USB drive
2.4 Peropesis live booting by using virtual machine, VirtualBox
3. Login / Logout
3.1 Login
3.2 Logout
3.3 Reboot the system
3.4 Shutting down the system
4. Applications
4.1 Program pwd
4.2 Program cd
4.3 Program ls
5. Help
5.1 Program man
5.2 Direktory /usr/share/doc
6. File system
6.1 Layout of the Peropesis file system
6.2 Installing temporary devices in the /mnt directory
6.3 To recover a faulty Linux operating system by using the chroot
7. Network
7.1 Basic (ethernet) connection
7.2 Wireless connection

1. Introduction

1.1 What is Linux

In 1991, Linus Torvalds began building the Linux kernel in his personal project. He started this project desiring to create a Unix-like operating system. The first version of the Linux was released in mid-September 1991.

Linux kernel was released publicly and free of charge, under the GNU GPL license. That way everyone could study it and make changes. Today hundreds of developers around the world are developing the Linux kernel and every day with Linux kernel created Linux operating systems is becoming increasingly popular.

The term "Linux" is attributable to the kernel. Linux kernel is an axis around which revolve various stand-alone applications or entire software packages. Kernel controls your computer's operations and ensures that all applications function properly.

Different companies and individuals combine Linux kernel with different applications and so creates operating systems. Each such bundling is called Linux distribution or node.

References

Torvalds L. (1992). LINUX's History. Link: https://www.cs.cmu.edu/~awb/linux.history.html


2. Booting

This chapter is intended to introduce you how to boot Peropesis Linux operating system to your computer.

There are several ways how to boot the Peropesis Linux OS live edition on your computer. One of them is boot from USB device, other is by using a virtual machine. Below is information on how to do this.


2.1 Save an ISO image of the Peropesis live operating system to a USB drive in Microsoft Windows environment

Required components:

ISO image of the Peropesis downloaded from this link: Get Peropesis;
100 MB or higher capacity USB media;
Application for saving files to USB media, for example, Rufus (if this program is not available on your computer, it needs to be download and install).

1. Insert a USB memory into the computer's USB port.
2. Open program Rufus.
3. In the field of Device of the program, select the USB device, to which we'd like to save the Peropesis ISO image.
4. In the field of Boot selection of the program, let's select FreeDOS (this will create an automatically bootable USB).
5. In program options, Partition scheme and Target system leave default options.
6. Press the SELECT button in the application and find, select and open Peropesis.iso file in an open files manager. After this step in the field of Volume label the existing information should have been updated to Peropesis.
7. All other options in the program, leave unchanged.
8. To start Peropesis.iso recording to USB key, press START button.
9. After step 8 program Rufus can display several warning notifications: for additional files installing; for ISOHybrid image recording; due to the destruction of data on the USB drive. If you got this warning notifications, press OK or YES. Before confirming the destruction of data on a USB device, check that there is no data left on the USB drive that is important to you.

If all options have been set correctly, after step 8 or step 9, the program Rufus had to start recording of Peropesis ISO file to selected USB drive. The status of the task should have changed to Copying ISO files… Because the ISO file of Peropesis live operating system is very small, copy process may take up to a minute (depending on your computer specifications). The program will alert you when the copy process is complete - in task status area, note Copying ISO files… will be updated to note Ready. This means that you have created an auto-bootable Peropesis live USB.

How to boot Peropesis live USB to your computer, see chapter 2.3 of this webpage.


2.2 Save an ISO image of the Peropesis live operating system to a USB drive in Linux environment

Required components:

ISO image of the Peropesis downloaded from this link: Get Peropesis;
100 MB or higher capacity USB media;
Application for saving files to USB media, for example, dd (accessible via command prompt interface) or one of the programs available in a graphical environment. In Debian-type systems, GNOME and KDE desktops environment most used application is Startup Disk Creator.


2.2.1 Save an ISO image by using the dd program available through the Shell interpreter

1. Connect a USB device to your computer.
2. Open Konsole. To save a ISO file of Peropesis to a USB drive, root authority will be required. Sign as root user. In the directory /dev find which USB device will be used to save the ISO file. USB devices are labeled with file sda, sdb, sdc etc. names in the directory /dev. Write a command on the console:

$ ls /dev/sd*

This command lists all devices on your computer. The last device in the list is the device that you need. To make sure, by one hundred percent, which device is right for you to record a mirror image, you can enter the ls command once with the media inserted in the USB slot and the next time without a USB media inserted. In each case, the number of devices in the list must be different. Also, if you want to know which devices are currently connected to your computer, you can do so using the lsblk or lsusb applications.
3. To save an ISO file to the default USB drive, we specify a command for the dd program:

# dd if=Peropesis.iso of=/dev/sd*

Because the ISO file of Peropesis live operating system is very small, copy process may take up to a minute (depending on your computer specifications).

How to boot Peropesis live USB to your computer, see chapter 2.3 of this webpage.


2.2.2 Save an ISO image by using the Startup Disk Creator program available through the graphical environment

1. Insert a USB memory into the computer's USB port.
2. Open program Startup Disk Creator.
3. The opened application checks your user's Downloads directory at startup and, if it contains an ISO file, program selects that file as the default. If you want to change the ISO file selected by the application, use the Other button in the application window. During startup, the program checks the USB medias connected to your computer and lists them in the field of Disk to use. Select your desired USB device.
4. If all program options are right for you, press the Make Startup Disk button. Before begin copying an ISO file to a USB drive, the program may display a warning message about the USB drive you have selected, so that we can double-check that there is no data left in the selected USB drive that will be destroyed when the Peropesis ISO file is saved. Check it and confirm.

If all options have been set correctly, the program Startup Disk Creator had to start recording of Peropesis ISO file to selected USB drive. The status of the task should have changed to Writing disk image... Because the ISO file of Peropesis live operating system is very small, copy process may take up to a minute (depending on your computer specifications). The program will alert you with an Installation complete notification when the copy process is complete. This means that you have created an auto-bootable Peropesis live USB.

How to boot Peropesis live USB to your computer, see chapter 2.3 of this webpage.


2.3 Peropesis live OS booting from USB drive

Immediately after the computer was turned on, the basic software starts. One of the main functions of this software is to initiate the startup of the operating system. Old type motherboards have the Basic input/output system - BIOS installed. New type motherboards have the Unified Extensible Firmware Interface - UEFI installed. The Peropesis Linux operating system is compatible with both BIOS and UEFI software.

If you want at startup your PC to boot the Peropesis operating system from the USB drive instead the main operating system which is in hard drive, you must complete two steps: insert a USB memory (with saved Peropesis OS) into the computer's USB port and, if necessary, change the current options (set a specific device to boot from) in the BIOS or UEFI setup program.

The BIOS or UEFI Setup program is opened by pressing the corresponding key immediately after the computer was turned on. Each computer manufacturer has a different opening key for the BIOS or UEFI Setup programs. The most common ones are: ESC, F1, F9, F10, F11, Del etc. Find the right key for your PC. In the BIOS or UEFI Setup program that is opened, select the Boot category and find the default USB device containing the Peropesis OS in the device list. Mark this USB device as the first or only device the operating system to boot from. Save this option, turn of the BIOS or UEFI setup program and if everything was done correctly, the next time of computer startup will boot the Peropesis operating system from the USB drive.

If the Peropesis operating system does not start at the next computer startup time and there are no UEFI USB or USB FLASH media (with Peropesis system) between all available boot devices, then your computer probably supports the UEFI interface. In this case, you should open the UEFI setup program and turn off the Security Boot option in the Boot category. If you turned off the Security Boot option and UEFI interface still does not identify USB devices (with Peropesis), then you should to try to turn on CSM or Legacy options in UEFI Setup. If everything was done correctly, the next time of computer startup only those devices will be identified, that contain recorded ISO images with BIOS enabled bootloaders. Note: if you have Windows installed on your hard disk, when you turn on CSM or Legacy options, devices that have Windows installed will no longer be identified on next computer startup.

How to login to Peropesis operating system, see chapter 3.


2.4 Peropesis live booting by using virtual machine, VirtualBox

A virtual machine is a type of program that creates a computer system emulation. This program extends personal computer functionality, providing it with the architectural features you want, that may be necessary to load the desired software. We'll use a VirtualBox virtual machine to boot the Peropesis operating system on your PC.

Required components:

If VirtualBox program is not available on your computer, it can be downloaded from this link and install on;
ISO image of the Peropesis downloaded from this link: Get Peropesis.

1. Open program VirtualBox.
2. Create a virtual machine:
2.1 in the Name and Operating system table, select the name for the virtual machine, specify the working directory, select the type of operating system (Linux, in this case), select one of the following Linux distributions (in this case, Other);
2.2 leave the default options in the Memory size table;
2.3 because we will use VirtualBox to load Peropesis ISO image in RAM, in the next step, Hard Disk, to create virtual hard drive is not necessary, so select Do not create a virtual hard disk. The program may inform you of this choice with a warning message. If this happens, check that you understand the message and create a virtual machine by clicking the continue and/or Create button;
2.4 if you did everything well in the previous steps, the program should have already created a virtual machine. In this step, we will specify a specific operating system for a virtual machine that has already been created. Select the Settings category from the top Menu bar. In the open Options table, select the Storage subcategory. In the Storage Devices section, select a device: Controller: AHCI (SATA) and add a Peropesis.iso file to it (press the green arrow Adds optical drive, find the Peropesis.iso file in the file manager that appears, select it and confirm it with the OK button);
2.5 now you can to try to load the Peropesis.iso file. Press the Start button on the top Menu bar. If everything was done correctly in the previous steps, the loading of the operating system must begin in the newly displayed window.

How to login to Peropesis operating system, see chapter 3.


3. Login / Logout

When the Peropesis operating system was loaded, on the screen you must see the login program called. Program login is used for signing onto a system. Signing to the Peropesis operating system means creating of a user session. This section provides instructions on how to create a new and end an existing user session. In this chapter also is discussed how to restart or how to completely shut down the Peropesis operating system.


3.1 Login

You may login to the Peropesis operating system as root user. There is no password created for this user, so program login will not require password. If you want to create a password for root user, use the program passwd. For example:

# passwd

Learn more about the passwd program and its options on the passwd(1) man pages.


3.2 Logout

If you want end root or any other user session, use the program logout. For example:

$ logout

If you want again to create new session on behalf of root user, login program will require a password (if you have previously created it for a root user).


3.3 Reboot the system

If you want to restart the Peropesis operating system, you can do so by using the shutdown program in conjunction with the restart option. For example:

# shutdown -r now


3.4 Shutting down the system

If you want to shut down the operating system completely, you must also use the shutdown program by setting it to the halt option. For example:

# shutdown -h now

Learn more about the shutdown program and its options on the shutdown(8) man pages.


4. Applications

In the Peropesis Linux file system, common destination programs are located in /bin, /sbin, /usr/bin and /usr/sbin directories. In order to familiarize yourself with these programs and then use them, before that, it is necessary to familiarise yourself with some of the main commands of programmes.

Because the Peropesis operating system is minimalist, a command-line-based system, all programs on this system are accessed through a command-line interface. Immediately after the Peropesis OS has been loaded in the computer's RAM and the system has been accessed on behalf of a root user, all programs can be called by specifying their names/commands in the command prompt.


4.1 Program pwd

Program pwd prints working directory or otherwise specifies which system directory you are in as a user.

$ pwd


4.2 Program cd

Program cd changes directory. For example, to access the root directory of a system, you would type the following command at a command prompt:

$ cd /

Conversely, to return to your /root user directory, you must type the following command at the command prompt:

$ cd /root


4.3 Program ls

Program ls (abbreviation for list) lists the files and directories in the specified directory. If you want to know which files or directories exist, for example, in the main system directory, you would type the following command at the command promp:

$ ls /

By using the ls command, you can find out what sharing programs make up the Peropesis operating system. Examples:

$ ls /bin
$ ls /sbin
$ ls /usr/bin
$ ls /usr/sbin

You can use the Peropesis man pages in order to know exactly, what each programs is for and how to use these programs. For more information about the man program, see the Help chapter below.


5. Help

You may often need information help, when you want to become familiar with a specific program. There are various ways to get it. This chapter describes the assisted support forms available on the Peropesis operating system.


5.1 Program man

man - an interface to the system reference manuals. man (short for manual) is a traditional form of documentation for Unix and Linux operating systems. man pages that contain specially-designed files are written for the majority of applications and are divided into sections. When you type command, man program_name, at the command prompt, the man page of the defined application is displayed. For example:

$ man pwd

There are lots of man pages. They are grouped into sections to make them easier to use. You can often see the names of program commands, programs, and even programming libraries with a section number next to their name. For example, you might see a recommendation to bash(1) page. This mark indicates that the bash application is documented in Section 1 (General commands). To tell program man that we need the first chapter application bash page, you must type the following command at the command prompt:

$ man 1 bash

Sections of man pages:

SectionContent
1General commands
2System calls
3Library functions, covering in particular the C standard library
4Special files (usually devices, those found in /dev) and drivers
5File formats and conventions
6Games and screensavers
7Miscellanea
8System administration commands and daemons

In addition near the program man in the operating system of Peropesis includes programs whatis and apropos. These applications are an integral part of the man software package. The purpose of these programs is to make it easier to search the system.

Program whatis provides a very short description of the programs on the system. Example:

$ whatis bash
bash (1) - GNU Bourne-Again SHell

Program apropos is used when you are requested to find man pages, that mention the keyword you provide. This is especially useful for finding programs without knowing their exact name. For axample:

$ apropos bash
bash (1) - GNU Bourne-Again SHell
builtins (1) - bash built-in commands, see bash(1)
rbash (1) - restricted bash, see bash(1)WaveLAN/IEEE 802.11 device driver

Note: To take advantage of the whatis and apropos applications available in the Peropesis system, you must first update man database by typing the following command at a command prompt:

$ /usr/bin/mandb

If you'd like to learn more about the man, whatis and apropos programs, you can read about it on the man pages.

References

A group of authors. man page. Link: https://en.wikipedia.org/wiki/Man_page
A group of authors. (1992). Slackware Linux Essentials. Link: http://www.slackbook.org/html/book.html#HELP-SYSTEM-MAN


5.2 Direktory /usr/share/doc

Most open source software comes with certain kinds of documentation - README files, instructions for use, licenses, etc. All types of documentation that comes with source code in the Peropesis operating system are located in the /usr/share/doc directory. Each program has its own directory for documentation. For example:

/usr/doc/$program-$version

In this case, the variable $program refers to the name of the software, and $version refers to the version of the software you have installed.

For a list of the documentation in the Peropesis system, you must type the following command at the command prompt:

$ ls /usr/share/doc/

To get familiar with the program's man documentation, you must type the following command at the command prompt:

$ cat /usr/share/doc/man-db/man-db-manual.txt | more


6. File system

The Linux file system contains a single main directory. This main directory is called root directory. root directory in the system is represented by a slash (/). Each directory in the root directory is called a subdirectory. Linux file system can be imagined as a file directive tree - root directory with several subdirectories branching from it and also hundreds if not thousands other other directories and files branching from these subdirectories. The development of the Linux file system is based on general filesystem hierarchy standards.


6.1 Layout of the Peropesis file system

The development of the Peropesis Linux file system is based on general filesystem hierarchy standard. The main root directory (/) contains the following directories:

DirectoryPurpose
/binDirectory for storing core programs.
/bootDirectory for storing required files on Linux boot, including Linux core image and initrd file system image.
/devDirectory for storage of device nodes / files.
/etcDirectory for storing configuration files.
/homeDirectory for storing for system users' home directories.
/libDirectory for storing programs libraries.
/lib64Directory for storing programs libraries, that support 64-bit software.
/mediaDirectory for storage of mounted media (floppy, cdrom, etc.).
/mntDirectory for storing temporarily installed devices (e.g. USB).
/optDirectory for storing second-tier software packages installed by system users.
/procA virtual file system stores information about kernel-controlled processes.
/rootHome directory for user root
/runThis directory stores information about users, that are currently logged on and running daemons.
/sbinDirectory for storing core programs.
/sysThis directory stores data about devices and some of the functions performed by the kernel.
/tmpDirectory for storing temporary files.
/usrSecond basic part of file system.
/varThe storage directory for files that contain variable content (for example, system logs).

References

A group of authors. Filesystem Hierarchy Standard. Link: https://refspecs.linuxfoundation.org/fhs.shtml


6.2 Installing temporary devices in the /mnt directory

The Peropesis operating system has the eudev software package installed. When a temporary device is plugged into any of the jacks on your computer, in /dev directory by eudev a node for that device is automatically created, expressed as a file name. USB devices connected to your computer are labeled with the sdx file name in the system. The letter x is a variable data. The first connected device is labeled with the sda name, the second sdb, etc.

You can use the lsblk program to check out whether USB devices are connected to your computer. Example:

$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:16 1 14.4G 0 disk
sr0 11:0 1 1024M 0 rom

The example shows, that a USB device, sda is connected to the system. so that we can scan from this device and record to it information, this device must be mounted in the Peropesis file system. A /mnt directory is used to mount temporary devices into the system. For installation of the device is used a mount program. Example:

# mount /dev/sda /mnt

We can use the ls command to scan information from a device sda, that is currently mounted into the /mnt directory:

$ ls /mnt
file1 file2 directory1/ directory2/

The example shows, that sda device has two files (file1 and file2) and two directories (directory1/ and directory2/). With other programs can create an additional file on this device, also the file, that is on the sda device can be saved to other Peropesis file system directories or a file that is on a Peropesis file system can be copied to a USB device.

The umount program is used for unmounting a device from the Peropesis file system. Example:

# umount /mnt


6.3 To recover a faulty Linux operating system by using the chroot

Live edition of the Peropesis operating system can be used for recovering working option of other, faulty operating system - by loading Peropesis system in the computer's memory, by mounting the current faulty system which is on the hard drive to Peropesis and by using the chroot Program for restoring corrupted libraries or other essential files.

Chroot program executes commands in a directory to which root authority is assigned. On many systems, only the super-user can do this. When, for some reason, such as, incorrect libraries are installed, normally the operating system stops booting, by mounting this corrupted system into another file system and by using the chroot program, then come up an possibility to modify information on a corrupted file system, in directories such as /lib64 or /sbin, this allows you to restore what has been damaged.

The following is a 4-step action plan, how to connect to a damaged file system by using the chroot program.

1. In the first step live edition of the Peropesis OS need to write to USB storage. Instructions on how to do this are provided in this chapter.
2. In the second step the Peropesis live OS, which is written to media need to load to computer, that has a damaged operating system, memory. Instructions on how to do this are provided in this chapter.
3. In the third step a faulty file system need to mount into the Peropesis file system. Usually, the Linux operating system, that is installed on your computer's disk has at least two partitions - swap and Linux. In the system, these partitions can be represented by sda1 and sda2 file names (file names also can be sdb, sdc, etc.). Only one of the following partitions should be installed in the Peropesis system, i.e. a partition containing Linux (not swap) file system. Partition type can be obtained from lsblk program. Example:

$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 500G 0 disk
├─sda1 8:1 0 498.5G 0 part /
└─sda2 8:2 0 1.5G 0 part [SWAP]

# mount /dev/sda2 /mnt

4. After the faulty file system has been mounted to the Peropesis file system /mnt directory, the chroot command can be executed. Example:

# chroot /mnt /bin/bash

After this command, the chroot program changes the main file system root directory into a new root directory and from then on, in subdirectories is opportunity to perform the desired actions. More information about chroot program options can be found on the chroot (1) man page.

exit command used to exit from chroot environment after actions is finished. Finally, the file system is unmounted from the /mnt subdirectory of the Peropesis file system. Example:

# exit

# umount /mnt

References

A group of authors. Run a command with a different root directory. Link: https://www.gnu.org/software/coreutils/manual/html_node/chroot-invocation.html#chroot-invocation
A group of authors. Chroot. Link: https://en.wikipedia.org/wiki/Chroot


7. Network

Peropesis supports two types of network connectivity, wired and wireless. This chapter describes how by using the Peropesis operating system to connect to a network in both of the following ways.


7.1 Basic (ethernet) connection

Program dhcpcd is installed in the Peropesis operating system. dhcpcd is a DHCP protocol client. DHCP - dynamic host configuration protocol, is a way to assign an IP address to a computer at startup. Client dhcpcd take an information (IP address, routes, and so on) from server dhcpd and automatically configures the network interface on the computer where it is installed and running. The program dhcpcd is initiated during the Peropesis system boot. The initialization script is described in the /etc/init.d/network file. This script contains two functions for creating and deleting loopback and ethernet interfaces. This script also includes "case" control construct of these functions. To sum up, when you type a commands: /etc/init.d/network start | stop | restart at a command line, then loopback and network (ethernet) interfaces are run, stoped or rebooted. For example:

If you want to create loopback and ethernet interfaces, you must type the following command at the command prompt:

# /etc/init.d/network start

If you want to stop loopback and ethernet interfaces, you must type the following command at the command prompt:

# /etc/init.d/network stop

If you want to stop and then immediately to re-create loopback and ethernet interfaces, you must type the following command at the command prompt:

# /etc/init.d/network restart

For more information about the dhcpcd (8) program, see on this program's man page.

In the system is installed ifconfig and route network configuration and control programs. Program ifconfig shows network interfaces in the system and it is designed to configure these interfaces. Program route show / manipulates the kernel's IP routing tables. For example:

If you want to get information about the network interfaces that are available on your system, you must type the following command at the command prompt:

# ifconfig -a

If you want to get information about existing routes in the system, you must type the following command at the command prompt:

# route

For more information about ifconfig (8) and route (8) programs, see on these program's man pages.

References

Roy Marples. dhcpcd. Link: https://roy.marples.name/projects/dhcpcd
A group of authors. Interface Configuration for IP. Link: http://www.faqs.org/docs/linux_network/x-087-2-iface.interface.html


7.2 Wireless connection

This section describes how to connect to wireless network access point.

1. The first step involves checking if a wireless network interface has been established in the loaded Peropesis system. This can be done by writing the following command on the command line:

# ifconfig -a

2. A list of available wireless access point can be found by using this command:

# iw dev interface scan | grep SSID

3. The following command is used to check interface status:

# iw dev interface link

4. If your device is not connected to an access point and, if wireless network access point is not password protected, the command below is used to connect to it:

# iw interface connect SSID

5. If wireless network access point is password protected (WPA or WPA2), wpa_supplicant and wpa_passphrase programs are used to control the wireless network auto authentication process. Example:

# wpa_supplicant -B -i interface -c <(wpa_passphrase MYSSID PASS)

Or other way:

# wpa_passphrase MYSSID PASS | cat > /etc/wpa_supplicant.conf
wpa_supplicant -B -i interface -c /etc/wpa_supplicant.conf

6. dhcpcd program will configure wireless network interface data automatically.

7. To connect to hidden wireless network access point, you need to create a configuration file /etc/wpa_supplicant.conf with the content in the example:

# cat > /etc/wpa_supplicant.conf << "EOF"
network={
ssid="SSID_name"
scan_ssid=1
psk="Password"
}
EOF

The wpa_supplicant program is used to start the auto identification process. The wpa_supplicant program must be instructed to retrieve login data from a previously created file. Example:

# wpa_supplicant -B -i interface -c /etc/wpa_supplicant.conf

For more information about iw (8), wpa_supplicant (8) and wpa_passphrase (8) programs, see on these program's man pages.

References

Paul Michel (2019/06/18). About iw. Link: https://wireless.wiki.kernel.org/en/users/Documentation/iw
Johannes Berg (2019/05/28). About nl80211. Link: https://wireless.wiki.kernel.org/en/developers/documentation/nl80211


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E-mail.: info(at)peropesis.org