Linux /Unix File Systems and Directories Command Line

Type of files used by Linux :

When working with Linux, you need to be aware of the fact that there are a number of different file types used by the file system. This is another area where the Linux file differ significantly from the widows file system. With a windows file system you basically have two different types in the file system.

Directories
Files

 

You can have normal file, hidden file, shortcut file, word processing file, executable file, etc.

However, these are a variety of different file type used by the system.

File type as shown below:

 

File Type

Description

Regular Files These files are like those used by the file systems of other operating system – e.g. Open Office.org files, executable files, images, text configuration files, etc.
Links These files are pointers that point to other files in the file system.
FIFOs FIFO stands for (First In First Out) these are special files used to move data from one running process on the system to another. A FIFO file is basically a queue where the first chunk of data added to the queue is the first chunk of the data removed from the queue. Data can only move in one direction through a FIFO.
Sockets Sockets are similar to FIFOs in that they are used to transfer information between sockets. With a socket, however, data can move bi-directionally.

Linux /Unix File Systems and Directories

Several major directories are associated with all modern Unix/Linux operating systems. These directories organize user files, drivers, kernels, logs, programs, utilities, and more into different categories. The standardization of the FHS makes it easier for user of other Unix-based operating systems to understand the basics of Linux. Every FHS start with the root directories, also known by its label, the single forward slash “/”. All the other directories shown in table are subdirectories of the root directory. Unless they are mounted separately, you can also find their files on the same partition as the root directory.

Command

Command Description

/ The root directory, the top level directory in the FHS. All other directories are sub directories of root, which is always mounted on same partition. All directories that are not mounted on a separate partition are include in the root directories partition.
/bin Essential command line utilities. Should not be mounted separately; otherwise, it could be difficult to get to these utilities when using a rescue disk.
/boot Includes Linux start up files, including the Linux Kernel. Can be small; 17MB usually adequate for a typical modular kernel. If you use multiple kernels, such as for testing a kernel upgrade, increase the size of this partition accordingly.
/etc Most basic configuration files.
/dev Hardware and software device drivers for everything from floppy drives to terminals. Do not mount this directory on separate partition.
/home Home directories are almost every user.
/lib Program library for the kernel and various command line utilities. Do not mount this directory on separate partition.
/mnt The mount point for the removable media including floppy drives, CD -ROM’s and zip disks.
/opt Application such as Wordperfect or Star Office.
/proc Currently running kernel-related process, including device assignment such as IRQ ports, I/O addresses, and DMA channels.
/root The home directory of the root user.
/sbin System administrator commands. Don’t mount this directory separately.
/tmp Temporary files. By default, Red Hat Linux deletes all files in this directory periodically.
/usr Small programs accessible to all user. Includes many system administrator commands and utilities.
/var Variable data, including log files and printer spools.

 

Some of the configuration files in  /etc directory that you should remember:

 

File

Function

/etc /fstab Lists the partition and file systems that will be automatically mounted when the system boots.
/etc /group Contains local group definitions.
/etc /grup.cong Contains configuration parameters for the GRUP boot loader (assuming its being used on the system).
/etc /hosts Contains a list of hostname-to-IP address mapping the system can use to resolve hostnames.
/etc /inittab Contains configuration parameter for the init process.
/etc /init.d/ A subdirectory that contains starup script for services install on the system. On Fedora or Red Hat system, these are located in /etc /rc.d /init.d.
/etc /modules.conf Contains configuration parameters for your kernel modules.
/etc /passwd Contains your system user account.
/etc /shadow Contains encrypted passwords for your user accounts.
/etc /X11/ Contains configuration files for X windows.

 

In this assignment I will instruct you about some basic commands of Linux. You will get seven virtual terminals when you perform fill installations. Although you can use graphics for daily task but here we are preparing for RHCE exam so you must use command line interface. Because all questions are based on command line in RHCE Exam.

 

-P. M. Sagavekar

RHCE (Red Hat Linux Certified Engineer) Skills

RHCE (Red Hat Linux Certified Engineer) SKILLS :

Troubleshooting and System Maintenance

RHCE must demonstrate the RHCE skills listed above, and should be able to:

  • Use the rescue environment provided by first installation CD
  • Diagnose and correct boot failure arising from boot, module, and file system errors
  • Diagnose and correct problems with network service (see installation and configuration below for a list of these services)
  • Add, remove, and resize logical volumes
  • Diagnose and correct networking services problem where SELinux contexts are interfering with proper operation.

 Installation And Configuration

RHSE must demonstrate the RHCT-level skills listed above, and they must be capable of configuring the following network services:

  • HTTP/HTTPS
  • SMB
  • NFS
  • FTP
  • WEB Proxy
  • SMTP
  • IMAP, IMAPS, and POP3
  • SSH
  • DNS(catching name server, slave name server)
  • NTP

For each of these services, RHCE must be able to:

  • Install the package needed to provide the service
  • Configure SE Linux to support the service
  • Configure the service to start when the system is booted
  • Configure the service for basic operation
  • Configure host-based and usre-based security for the service
  • RHCE must also be able to:
  • Configure hands-free installation using kick start
  • Implement logical volumes at install-time
  • Use Ip tables to implement packet filtering and/or NAT
  • Use PAM to implement user-level restrictions

Based on this RHCE guide we have created step by step guide of RHCE exam, By our RHCE guide you can get your RHCE certificates. We have managed various practical examples and suggest you to go through all these.

Everything in Linux can be reduced to a file, partitions are associated with files such as/ dev/hda1. Hardware components are associated with file such as / dev/modem. Detected device are documented as files in the /proc directory. The File system Hierarchy standard (FHS) is the official way to organize files in Unix and Linux directories.

 

-P. M. Sagavekar

RHCT (Red Hat Linux Certification Training) Skills

RHCT (Red Hat Linux Certification Training) Skills

 Troubleshooting and System Maintenance

RHCTs should be able to:
  • Boot systems into different run levels for troubleshooting and system maintenance
  • Diagnose and correct misconfigured networking
  • Diagnose and correct hostname resolution problems
  • Configure the X Window System and a desktop environment
  • Add new partitions, file systems, and swap to existing systems
  • Use standard command-line tools to analyses problems and configure system

Installation And Configuration:

  • RHCT must be able to:
  • Perform network OS installation
  • Implement a custom partitioning scheme
  • Configure printing
  • Configure the scheduling of task using cron and at
  • Attach system to a network directory service, such as NIS or LDAP
  • Configure autofs
  • Add and manage users, groups, quotas, and file Access Control Lists
  • Configure file system permissions for collaboration
  • Install and update package using rpm
  • Properly update the kernel package
  • Configure the system to update/install package from remote repositories using yum or pup
  • Modify the system boot loader
  • Implement software RAID at install-time and run-time
  • Use /proc/sys and sysctl to modify and set kernel run-time parameters
  • Use scripting to automate system maintenance tasks

Configure NTP for time synchronization with a higher-stratum server.

 

-P. M. Sagavekar

Red Hat Linux Certifications and Exam Detail’s

Red Hat Linux Certifications and Exam Detail’s

 

RHCE Courses and Exam:

 

As part of its RHCE program, Red Hat offer several courses designed to prepare candidates for the RHCE exam. Candidates must take course RH302, which is the exam itself. However, candidates can take none, some. or all of the other courses. This section describes the RHCE courses offered by Red Hat, as well as the RH302 exam.

 

RH033: Introduction to red Hat Linux I,II

 

RH033 is a dour day course intended for users who have no previous Unix or Linux experience, students should, however, have previous experience with a computer, including use of a mouse and graphical user interface. Upon completion of the course, the student should be able to use and customize the GNOME desktop and be able to use the Linux command shell.

 

RH133: Red Hat Linux system Admin I, II

 

RH133 is a four-day course intended for users who are familiar with Red hat Linux. Before taking this course, students should complete RH033 or possess equivalent experience. Upon completion of the course, student should be able to install and configure Red Hat Linux, X, and various network services and clients, such as DHCP, NIS, NFS, and Samba. Student should also be able to perform basic troubleshooting and rebuild the Linux kernel from source code.

 

RH253: Red Hat Linux Networking and Security Admin

 

RH253 is four-day course intended for Unix or Linux system administrators. Before taking this course, student should complete RH133 or possess equivalent experience. Upon completion of the course, student should be able to install and configure network services such as Apache, DHCP, DNS, FTP, Samba, NFS, send mail, and IMAP4/ POP3 mail. Student should also be able to establish and administrator a security policy that includes such elements as password security kernel security, public / private key encryption, kerberos, secure shell, and firewalls.

 

RH300: RHCE (Red Hat Certified Engineer)

 

  1. RH300 is five-day course that include RH302, the RHCE exam, as an integral part of the course. Before taking this course, students should complete RH253 or possess equivatent experience and have experience as a Unix or Linux system or network administrator. The course consists of four days of instruction, and the fifth day is devoted to the RHCE exam. Upon completion of the course, student should be prepared to manage a Red Hat Linux system that offers common TCP / IP service, such as FTP and HTTP. The course include eight units of instruction, each of which has one or more hands-on labs associated with the following topics:

 

  1. Hardware and Installation (x86 Architecture)
  2. configuration and administration
  3. Alternate installation Methods
  4. Kernel Services and Configuration
  5. Standard Networking Services
  6. X Windows System
  7. User and Host Security
  8. Routers, Firewalls, Clusters, and Troubleshooting

 

RH302: RHCE (Red Hat Certified Engineer) Exam

Though styled by Red Hat as a course, RH302 is not a course in the ordinary sense of the word. Instead, RH302 is the RHCE exam, which has duration of one day. RH302 is the only course that RHCE candidates must take. The exam consists of the following three closed-book components:

 

    Diagnosis and troubleshooting lab (2 1/ 2 hours)

    Installation and configuration lab ( 2 1/ 2 hours)

    Multiple choice exam (1 hour)

Effective May 1, 2009, the RECE exam is a single section lasting 3.5 hours,. Previously, it had been two section lasting a combined 5.5 hours. The content has been consolidated and reorganized into a single section in which time is used more efficiently. The RHCE exam consists of RHCE components (essentially the RHCE exam) plus RHCE-specific components. It is possible to earn RHCT in an RHCE exam if one has met the RHCT requirements but not the RHCE ones.

The components are not always presented in the same sequence. The course instructor, who acts as the exam proctor, will determine the sequence and announce it early in the day. The three components are equally weighted at 100 points each. The minimum passing score is 240 points, or 80 percent. However, the candidate must score at least 50 Points (50 %) on each exam component to pass the exam.

Study point for the RHCE Exam use standerd command line tool (e.g. ls, cp, mv, rm, tail, cat, etc.) to create, remove, view and investigate files and directories use grep, sed and awk to process text streams and files use a terminal-based text editor, such a vim or nano to modify text files. Use input ooutput redirection understand basic principles of TCP/IP networking, including IP addresses, net mask and getways for Ipv4 and Ipv6 use su to switch user accounts use passwd to set passwords.

Use tar, gzip and bzip2 configure and email client on RED HAT Enterprises Linux use text and/or graphical browser to access HTTP/HTTPS URL’s use lftp to access FTP URL’s.

 

-P. M. Sagavekar

Benefits of Linux

Benefits of Linux

We going to learn benefits of Linux.

Linux is mostly used by programmer as well as regular computer user all around the world.

Linux benefit mentioned below:

  • Linux is giving free of coast operating system, Linux offers free OS for daily users and programmer as well. You don’t want to spent money for this operating system like other Windows operating system.
  • Linux is open source operating system because of that any programmer can modify this OS.
  • You are not needed an antivirus when your using Linux operating system
  • Linux operating system is a highly secure operating system
  • GDC (Global Development Community) is constantly work for more enhance this security.
  • In every upgrade it becomes more secure and good built up
  • Google, Facebook etc. this big companies using Linux servers for maintaining there websites; because of Linux OS stability, security and reliability they using it.
  • Linux OS based servers could be run without reboot for many months
Linux Courses and Exam – RHCE (Red Hat Certified Engineer) Exam & Courses:

RHCE exam assesses the candidate’s ability to do the following:

  • Install and configure Red Hat Linux
  • Configure file systems and network
  • Configure X, the graphical user interface used on Unix and Linux systems
  • Configure basic security
  • Configure network services
  • Perform routine maintenance
  • Perform diagnostics and troubleshooting

Because Red Hat regularly updates its Linux distribution, RHCE certification is not valid indefinitely. However, according to Red Hat policy, RHCE certification remains valid for at least one year.

Red Hat Enterprises Certifications:

  • Red Hat Certified System Administrator (RHCSA)
  • Red Hat Certified Engineer (RHCE)
  • Red Hat Certified Architect (RHCA)
  • Red Hat Certified Engineer in Red Hat OpenStack
  • Red Hat Certified Enterprise Application Developer
  • Red Hat Certified Enterprise Microservices Developer
  • Red Hat Certified System Administrator in Red Hat OpenStack
  • Red Hat Certified Specialist in Hybrid Cloud Management
  • Red Hat Certified Specialist in Gluster Storage Administration
  • Red Hat Certified Specialist in Data Virtualization
  • Red Hat Certified Specialist in Virtualization
  • Red Hat Certified Specialist in Enterprise Application Server Administration
  • Red Hat Certified Specialist in Business Rules
  • Red Hat Certified Specialist in Business Process Design
  • Red Hat Certified Specialist in Camel Development
  • Red Hat Certified Specialist in Deployment and Systems Management
  • Red Hat Certified Specialist in High Availability Clustering
  • Red Hat Certified Specialist in OpenShift Administration
  • Red Hat Certified Specialist in OpenShift Application Development
  • Red Hat Certified Specialist in Server Security and Hardening
  • Red Hat Certified Specialist in Linux Performance Tuning
  • Red Hat Certified Specialist in Fast-Cache Application Development
  • Red Hat Certified Specialist in Configuration Management
  • Red Hat Certified Specialist in Linux Diagnostics and Troubleshooting
  • Red Hat Certified Specialist in Ansible Automation
  • Red Hat Certified Specialist in Messaging Administration
  • Red Hat Certified Specialist in Ceph Storage Administration
  • Red Hat Certified Specialist in Identity Management

Red Hat Certified Specialist in Security: Linux

Red Hat Enterprises Certifications Codes:

  • EX125 – Red Hat Certified Specialist in Ceph Storage Administration exam
  • EX183 – Red Hat Certified Enterprise Application Developer exam
  • EX200 – Red Hat Certified System Administrator (RHCSA) exam
  • EX210 – Red Hat Certified System Administrator in Red Hat OpenStack exam
  • EX220 – Red Hat Certified Specialist in Hybrid Cloud Management exam
  • EX236 – Red Hat Certified Specialist in Gluster Storage Administration exam
  • EX248 – Red Hat Certified Specialist in Enterprise Application Server Administration exam
  • EX280 – Red Hat Certified Specialist in OpenShift Administration exam
  • EX283 – Red Hat Certified Enterprise Microservices Developer exam
  • EX288 – Red Hat Certified Specialist in OpenShift Application Development exam
  • EX300 – Red Hat Certified Engineer (RHCE) exam
  • EX310 – Red Hat Certified Engineer in Red Hat OpenStack exam
  • EX318 – Red Hat Certified Specialist in Virtualization exam
  • EX342 – Red Hat Certified Specialist in Linux Diagnostics and Troubleshooting exam
  • EX362 – Red Hat Certified Specialist in Identity Management exam
  • EX403 – Red Hat Certified Specialist in Deployment and Systems Management exam
  • EX405 – Red Hat Certified Specialist in Configuration Management exam
  • EX407 – Red Hat Certified Specialist in Ansible Automation exam
  • EX413 – Red Hat Certified Specialist in Server Security and Hardening exam
  • EX415 – Red Hat Certified Specialist in Security: Linux exam
  • EX421 – Red Hat Certified Specialist in Camel Development exam
  • EX427 – Red Hat Certified Specialist in Business Process Design exam
  • EX436 – Red Hat Certified Specialist in High Availability Clustering exam
  • EX440 – Red Hat Certified Specialist in Messaging Administration exam
  • EX442 – Red Hat Certified Specialist in Linux Performance Tuning exam
  • EX450 – Red Hat Certified Specialist in Data Virtualization exam
  • EX453 – Red Hat Certified Specialist in Fast-Cache Application Development exam
  • EX465 – Red Hat Certified Specialist in Business Rules exam

-P. M. Sagavekar

What is Linux? Introduction of Linux

Thanks for joining us!

We going to learn what is Linux?

 

Linux is an Operating System (OS) which is free of cost and Open Source Operating System (OS) built with the Linux Kernel. Linux is well knows as Desktop operating System (OS) and server use as well. Linux Operating System (OS) is based on Linux Kernel, Linux Operating System (OS) released on “17th Sep. 1991” developed by “Linus Torvalds“. Linux Operating System (OS) is based on UNIX, Users can customize and make variations of the source code, known as distributions, for computer systems and other devices.

Linux Operating System (OS) is same as other Operating System (OS) like Windows XP, Windows 7, etc. software’s which is manages hardware with your desktop or laptop. Linux Operating System (OS) mostly using for on servers and others mega systems like mainframe computers, & this only OS supercomputers. Few of the Linux distributors are Linux Mint, Ubuntu, CentOS, Fedora, Debian, and Arch Linux all together with enterprise distribution like Red Hat Enterprises Linux and Linux Enterprise Server [SUSE]. Those are provided by GNU project – is a free software & mass collaboration project; GNU packages consist of OS utilities and tools like shell.

Powerful OS, Secure-Linux & Flexibility in Linux OS

Linux can formed in two different part of formed.

  • It consist of technical aspects which differentiate with other operating systems. in that, and other things. Linux operating system reduced virus attach risk & antivirus need to be used by specialist.
  • Linux operating system you can customise and modified as per your own, if you know how to do this. Linux provide flexibility in this operating system.
  • windows is limited in a single UI (User Interface), In Linux you can choose multiple options of UI (User Interface).
  • You can use Linux operating system on old and slow hardware as well as Super-Computer and new hardware also. (Note- World’s 90% Super-Computers are running on various Linux Operating System)
  • Linux has a strong encryption, design with security its provides advance features of standard.

Linux OS included some of parts

  • Bootloader
  • Kernal
  • Daemons
  • Shell
  • Graphical Server
  • Desktop Environment
  • Applications

-P. M. Sagavekar