Magnon Solutions Linux System Administrator Interview Questions, Process, and Tips

To configure Apache server in Red Hat 7.9, follow these steps:

• Install Apache using yum package manager

• Start Apache service and enable it to start at boot

• Configure firewall to allow HTTP traffic

• Create virtual hosts for multiple websites

• Configure SSL/TLS encryption for secure connections

To set permissions in a directory, use the chmod command followed by the desired permission code.

• Use the chmod command followed by the permission code (e.g. chmod 755 directory_name)

• The permission code consists of three digits, each representing the permission for owner, group, and others respectively

• The digits are calculated by adding the values of the desired permissions (read=4, write=2, execute=1)

• For example, 755 m...read more

To create LVM partition, first create physical volumes, then create volume group and finally create logical volumes.

• Use pvcreate command to create physical volumes

• Use vgcreate command to create volume group

• Use lvcreate command to create logical volumes

• Use mkfs command to create file system on logical volumes

lsblk command is used to list block devices in RHEL.

• Displays information about all available or the specified block devices.

• Shows the device name, size, mount point, and file system type.

• Can be used to identify unmounted disks or partitions.

• Can also be used to check the status of a disk or partition.

• Example: lsblk -a -o NAME,SIZE,MOUNTPOINT,FSTYPE

To create a blank file in RHEL, you can use the 'touch' command.

• Open the terminal in RHEL.

• Use the 'touch' command followed by the desired file name to create a blank file.

• For example, to create a file named 'example.txt', you would run: touch example.txt

• The 'touch' command can also be used to update the timestamp of an existing file.

To install packages in RHEL, use the yum package manager.

• Open the terminal and log in as root or use sudo

• Use the command 'yum install package_name' to install a package

• Use 'yum search keyword' to search for a package

• Use 'yum update' to update all installed packages

• Use 'yum remove package_name' to remove a package

yum is a package manager for RPM-based Linux distributions, while wget is a command-line tool for downloading files from the internet.

• yum is used for installing, updating, and removing packages on a system

• wget is used for downloading files from the internet, including packages

• yum uses repositories to manage packages, while wget can download files from any URL

• yum can resolve dependencies automatically, while wget does n...read more

To add a local repo in RHEL 7.2, create a .repo file in /etc/yum.repos.d/ directory.

• Create a .repo file in /etc/yum.repos.d/ directory

• Add the necessary details like name, baseurl, enabled, gpgcheck, etc. in the .repo file

• Save the file and run 'yum clean all' command to clear the cache

• Run 'yum repolist' command to verify if the local repo is added successfully

Cron tab is a time-based job scheduler in Linux used to automate repetitive tasks. It runs in the background and executes commands at specified intervals.

• Cron tab is configured using the 'crontab' command

• Each user has their own crontab file located in /var/spool/cron/crontabs/

• The syntax for setting up a cron job is: * * * * * command-to-be-executed

• The five asterisks represent the minute, hour, day of the month, month, ...read more

RHEL is a commercial distribution with paid support, while CentOS is a free, community-driven distribution.

• RHEL is developed by Red Hat and requires a paid subscription for support and updates.

• CentOS is a community-driven distribution that is free to use and receives updates from the community.

• Both distributions are based on the same source code and are binary compatible.

• CentOS is often used as a free alternative to RH...read more

To kill a process in RHEL 7.2, use the 'kill' command followed by the process ID.

• Identify the process ID using 'ps' command

• Use 'kill' command followed by the process ID to terminate the process

• Use 'kill -9' command to force kill the process if it doesn't respond to regular kill command