Senior Linux System Administrator Interview Questions and Answers

RAID stands for Redundant Array of Independent Disks. It is a data storage technology that combines multiple physical disks into a single logical unit.

• There are several types of RAID, including RAID 0, RAID 1, RAID 5, RAID 6, RAID 10, and more.

• RAID 0 offers no redundancy but provides improved performance by striping data across multiple disks.

• RAID 1 provides mirroring of data across two disks, offering redundancy but no performance improvement.

• RAID 5 uses striping with parity...read more

Free up disk space by identifying and removing unnecessary files.

• Identify large files and delete them

• Remove old log files

• Clear cache and temporary files

• Compress large files

• Move files to another disk or server

I have worked on Red Hat Enterprise Linux versions 6, 7, and 8.

• I have experience with installation, configuration, and maintenance of Red Hat Enterprise Linux servers.

• I have worked with Red Hat Enterprise Linux 6, 7, and 8 in both physical and virtual environments.

• I have experience with package management, user management, and security hardening on Red Hat Enterprise Linux.

• I have also worked with Red Hat Satellite for patch management and automation.

• Examples of projects I hav...read more

Zombie is a terminated process that still has an entry in the process table, while orphan is a child process whose parent has terminated.

• Zombie process is waiting for its parent to read its exit status

• Orphan process is adopted by init process (PID 1)

• Zombie process can be removed by killing its parent process

• Orphan process can continue running even after its parent has terminated

Network bonding is the process of combining multiple network interfaces into a single logical interface.

• Network bonding provides redundancy and increased bandwidth.

• There are different bonding modes such as active-backup, balance-rr, and LACP.

• Bonding can be configured using the ifenslave utility or through network configuration files.

• Examples of network interfaces that can be bonded include Ethernet, Wi-Fi, and InfiniBand.

• Bonding can be used in high availability setups or for ...read more

Booting process is the sequence of events that occur when a computer system is turned on.

• BIOS/UEFI firmware initializes hardware components

• Bootloader loads the kernel into memory

• Kernel initializes system processes and drivers

• Init system starts user space processes and services

• Graphical user interface (GUI) is loaded for user interaction

systemd is a system and service manager while services are individual programs that run in the background.

• systemd is responsible for managing the system's startup and shutdown processes

• services are individual programs that run in the background and can be managed by systemd

• systemd can start, stop, restart, enable, and disable services

• services can be configured to start automatically at boot time using systemd

• systemd provides better logging and error reporting for services com...read more

Headless services in Kubernetes are used for stateful applications that require stable network identities.

• Headless services do not have a cluster IP address

• They are used for stateful applications that require stable network identities

• They return the IP addresses of the pods directly

• They are defined by setting the cluster IP to None in the service definition