{"id":13526,"date":"2019-04-03T07:22:55","date_gmt":"2019-04-03T07:22:55","guid":{"rendered":"http:\/\/www.appservgrid.com\/paw92\/?p=13526"},"modified":"2019-04-03T07:22:55","modified_gmt":"2019-04-03T07:22:55","slug":"rhcsa-red-hat-certified-system-administrator","status":"publish","type":"post","link":"https:\/\/www.appservgrid.com\/paw92\/index.php\/2019\/04\/03\/rhcsa-red-hat-certified-system-administrator\/","title":{"rendered":"RHCSA (Red Hat Certified System Administrator)"},"content":{"rendered":"

RHCSA Series: Reviewing Essential Commands & System Documentation \u2013 Part 1<\/h1>\n

RHCSA<\/strong>\u00a0(Red Hat Certified System Administrator<\/strong>) is a certification exam from Red Hat company, which provides an open source operating system and software to the enterprise community, It also provides support, training and consulting services for the organizations.<\/p>\n

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\"RHCSA<\/a><\/p>\n

RHCSA Exam Preparation Guide<\/p>\n<\/div>\n

RHCSA<\/strong>\u00a0exam is the certification obtained from Red Hat Inc, after passing the exam (codename\u00a0EX200<\/strong>). RHCSA exam is an upgrade to the\u00a0RHCT<\/strong>\u00a0(Red Hat Certified Technician<\/strong>) exam, and this upgrade is compulsory as the Red Hat Enterprise Linux was upgraded. The main variation between RHCT and RHCSA is that RHCT exam based on RHEL 5, whereas RHCSA certification is based on RHEL 6 and 7, the courseware of these two certifications are also vary to a certain level.<\/p>\n

This Red Hat Certified System Administrator (RHCSA) is essential to perform the following core system administration tasks needed in Red Hat Enterprise Linux environments:<\/p>\n

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  1. Understand and use necessary tools for handling files, directories, command-environments line, and system-wide \/ packages documentation.<\/li>\n
  2. Operate running systems, even in different run levels, identify and control processes, start and stop virtual machines.<\/li>\n
  3. Set up local storage using partitions and logical volumes.<\/li>\n
  4. Create and configure local and network file systems and its attributes (permissions, encryption, and ACLs).<\/li>\n
  5. Setup, configure, and control systems, including installing, updating and removing software.<\/li>\n
  6. Manage system users and groups, along with use of a centralized LDAP directory for authentication.<\/li>\n
  7. Ensure system security, including basic firewall and SELinux configuration.<\/li>\n<\/ol>\n

    To view fees and register for an exam in your country, check the\u00a0RHCSA Certification<\/a>\u00a0page.<\/p>\n

    In this 15-article RHCSA series, titled Preparation for the RHCSA (Red Hat Certified System Administrator) exam, we will going to cover the following topics on the latest releases of\u00a0Red Hat Enterprise Linux 7<\/strong>.<\/p>\n

    Part 1<\/b>:\u00a0Reviewing Essential Commands & System Documentation<\/b><\/div>\n
    Part 2<\/b>:\u00a0How to Perform File and Directory Management in RHEL 7<\/a><\/div>\n
    Part 3<\/b>:\u00a0How to Manage Users and Groups in RHEL 7<\/a><\/div>\n
    Part 4<\/b>:\u00a0Editing Text Files with Nano and Vim \/ Analyzing text with grep and regexps<\/a><\/div>\n
    Part 5<\/b>:\u00a0Process Management in RHEL 7: boot, shutdown, and everything in between<\/a><\/div>\n
    Part 6<\/b>:\u00a0Using \u2018Parted\u2019 and \u2018SSM\u2019 to Configure and Encrypt System Storage<\/a><\/div>\n
    Part 7<\/b>:\u00a0Using ACLs (Access Control Lists) and Mounting Samba \/ NFS Shares<\/a><\/div>\n
    Part 8<\/b>:\u00a0Securing SSH, Setting Hostname and Enabling Network Services<\/a><\/div>\n
    Part 9<\/b>:\u00a0Installing, Configuring and Securing a Web and FTP Server<\/a><\/div>\n
    Part 10<\/b>:\u00a0Yum Package Management, Automating Tasks with Cron and Monitoring System Logs<\/a><\/div>\n
    Part 11<\/b>:\u00a0Firewall Essentials and Control Network Traffic Using FirewallD and Iptables<\/a><\/div>\n
    Part 12<\/b>:\u00a0Automate RHEL 7 Installations Using \u2018Kickstart\u2019<\/a><\/div>\n
    Part 13<\/b>:\u00a0Mandatory Access Control Essentials with SELinux<\/a><\/div>\n
    Part 14<\/b>:\u00a0Setting Up LDAP-based Authentication in RHEL 7<\/a><\/div>\n
    Part 15<\/b>:\u00a0Essentials of Virtualization and Guest Administration with KVM<\/a><\/div>\n

    In this\u00a0Part 1<\/b>\u00a0of the RHCSA series, we will explain how to enter and execute commands with the correct syntax in a shell prompt or terminal, and explained how to find, inspect, and use system documentation.<\/p>\n

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    \"RHCSA:<\/a><\/p>\n

    RHCSA: Reviewing Essential Linux Commands \u2013 Part 1<\/p>\n<\/div>\n

    Prerequisites:<\/h4>\n

    At least a slight degree of familiarity with basic Linux commands such as:<\/p>\n

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    1. cd command<\/a>\u00a0(change directory)<\/li>\n
    2. ls command<\/a>\u00a0(list directory)<\/li>\n
    3. cp command<\/a>\u00a0(copy files)<\/li>\n
    4. mv command<\/a>\u00a0(move or rename files)<\/li>\n
    5. touch command<\/a>\u00a0(create empty files or update the timestamp of existing ones)<\/li>\n
    6. rm command (delete files)<\/li>\n
    7. mkdir command (make directory)<\/li>\n<\/ol>\n

      The correct usage of some of them are anyway exemplified in this article, and you can find further information about each of them using the suggested methods in this article.<\/p>\n

      Though not strictly required to start, as we will be discussing general commands and methods for information search in a Linux system, you should try to install\u00a0RHEL 7<\/b>\u00a0as explained in the following article. It will make things easier down the road.<\/p>\n

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      1. Red Hat Enterprise Linux (RHEL) 7 Installation Guide<\/a><\/li>\n<\/ol>\n

        Interacting with the Linux Shell<\/h3>\n

        If we log into a Linux box using a\u00a0text-mode<\/b>\u00a0login screen, chances are we will be dropped directly into our default shell. On the other hand, if we login using a graphical user interface (GUI), we will have to open a shell manually by starting a terminal. Either way, we will be presented with the user prompt and we can start typing and executing commands (a command is executed by pressing the\u00a0Enter<\/b>\u00a0key after we have typed it).<\/p>\n

        Commands are composed of two parts:<\/p>\n

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        1. the name of the command itself, and<\/li>\n
        2. arguments<\/li>\n<\/ol>\n

          Certain arguments, called\u00a0options<\/b>\u00a0(usually preceded by a hyphen), alter the behavior of the command in a particular way while other arguments specify the objects upon which the command operates.<\/p>\n

          The\u00a0type<\/b>\u00a0command can help us identify whether another certain command is built into the shell or if it is provided by a separate package. The need to make this distinction lies in the place where we will find more information about the command. For shell built-ins we need to look in the shell\u2019s man page, whereas for other binaries we can refer to its own man page.<\/p>\n

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          \"Check<\/a><\/p>\n

          Check Shell built in Commands<\/p>\n<\/div>\n

          In the examples above,\u00a0cd<\/b>\u00a0and\u00a0type<\/b>\u00a0are shell built-ins, while\u00a0top<\/b>\u00a0and\u00a0less<\/b>\u00a0are binaries external to the shell itself (in this case, the location of the command executable is returned by\u00a0type<\/b>).<\/p>\n

          Other well-known shell built-ins include:<\/p>\n

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          1. echo command<\/a>: Displays strings of text.<\/li>\n
          2. pwd command<\/a>: Prints the current working directory.<\/li>\n<\/ol>\n
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            \"More<\/a><\/p>\n

            More Built in Shell Commands<\/p>\n<\/div>\n

            exec command<\/h6>\n

            Runs an external program that we specify. Note that in most cases, this is better accomplished by just typing the name of the program we want to run, but the\u00a0exec<\/b>\u00a0command has one special feature: rather than create a new process that runs alongside the shell, the new process replaces the shell, as can verified by subsequent.<\/p>\n

            # ps -ef | grep [original PID of the shell process]\r\n<\/pre>\n
            When the new process terminates, the shell terminates with it. Run\u00a0exec top<\/b>\u00a0and then hit the\u00a0q<\/b>\u00a0key to quit top. You will notice that the shell session ends when you do, as shown in the following screencast:<\/p>\n
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