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First, mount your CentOS 7 installation DVD. For example, let us mount the installation media on   /mnt   directory. mount /dev/cdrom /mnt/ Now the CentOS installation DVD is mounted under   /mnt   directory. Next install vsftpd package and let the packages available over FTP to your local clients. To do that change to /mnt/Packages directory: cd /mnt/Packages/ Now install vsftpd package: rpm -ivh vsftpd-3.0.2-9.el7.x86_64.rpm Enable and start vsftpd service: systemctl enable vsftpd systemctl start vsftpd We need a package called “createrepo”  to create our local repository. So let us install it too. If you did a minimal CentOS installation, then you might need to install the following dependencies first: rpm -ivh libxml2-python-2.9.1-5.el7.x86_64.rpm rpm -ivh deltarpm-3.6-3.el7.x86_64.rpm rpm -ivh python-deltarpm-3.6-3.el7.x86_64.rpm Now install “createrepo” package: rpm -ivh createrepo-0.9.9-23.el7.noarch.rpm Build Local Repository ...

TOPICS Boot Process Kernel Hardware and Kernel PROC and SYSCTL Logs Overview and SYSLOG BIOS initializes . BIOS calls boot loader, in RHEL it is GRUB. Bootloaders loads the first kernel image. GRUB then hands control to kernel which mounts the file system and start appropriates system services. The system services start up and log-in screen is displayed. KERNEL BOOT PROCESS kernel detects the hardware on the system and loads device drivers from its initial RAM file system initramfs-<kernel version>.img mount the root files system in read-only mode init is loaded LAST START UP STAGE init runs the necessary scripts in /etc/init. /etc/inittab is read for the default runlevel. Scripts for appropriate runlevel are started. User is presented with log in screen. GRUB (Grand Unified Boootloader) it works in two stages 1 st is a small program in first 446 bytes of boot sector 2 ...

CentOS 7 / RHEL 7 Check The Current Runlevel  You still can use “runlevel” command to check the current level, also can use another two commands. 1 2 3 systemctl get-default Or ll / etc / systemd / system / default.target Output: [root@itsprite Desktop]# systemctl get-default graphical.target 1 2 [ root @ itsprite Desktop ] # ll /etc/systemd/system/default.target lrwxrwxrwx. 1 root root 36 Nov 27 09: 31 / etc / systemd / system / default.target - > / lib / systemd / system / graphical.target CentOS 7 / RHEL 7 Supported Runlevel Using the followding command to get out the available runlevel, type: 1 systemctl list-units --type =target Output: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 [ root @ itsprite Desktop ] # systemctl list-units --type=target UNIT                LOAD   ACTIVE SUB    DESCRIPTION basic.target     ...