Interview Questions and Answers

The 'user lock' and 'user unlock' commands are used to lock and unlock user accounts in Linux.

• To lock a user account, use the 'usermod' command with the '-L' option followed by the username.

• Example: usermod -L username

• To unlock a user account, use the 'usermod' command with the '-U' option followed by the username.

• Example: usermod -U username

To create LVM, first create physical volumes, then create a 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 lvextend command to extend logical volumes

• Use lvreduce command to reduce logical volumes

LUN stands for Logical Unit Number. It is a unique identifier for a logical unit on a storage area network (SAN).

• LUN is used to identify a specific disk or partition on a SAN.

• It is used in conjunction with SCSI protocol to access storage devices.

• LUNs can be created and managed using tools like LVM or multipath.

• LUNs can be shared between multiple servers for high availability and load balancing.

• Example: /dev/sdb is a LUN that can be mounted on a Linux system.

Workload in Linux refers to the amount of work being done by the system at a given time.

• Workload can include tasks such as running processes, handling network requests, and managing system resources.

• Monitoring workload is important for ensuring system performance and stability.

• Tools like top, htop, and sar can be used to track and analyze workload.

• High workload can lead to system slowdowns or crashes.

• Balancing workload across multiple servers can help improve overall system e...read more

The Linux kernel is the core component of the Linux operating system, responsible for managing hardware resources and providing essential services.

• The Linux kernel is open-source and developed by a community of developers worldwide.

• It is released under the GNU General Public License (GPL).

• The kernel version can be checked using the 'uname -r' command.

• Examples of popular Linux kernel versions include 2.6, 3.x, 4.x, and 5.x.

ACL stands for Access Control List, a set of permissions attached to an object that specifies which users or system processes are granted access to that object.

• ACLs are used to control access to files, directories, and other resources on a system.

• They define who can read, write, or execute a file or directory.

• ACLs can be set on a per-user or per-group basis, allowing for more granular control over access permissions.

• Examples of ACL commands in Linux include setfacl and getfac...read more

LVM (Logical Volume Manager) is a tool used in Linux to manage storage by creating logical volumes from physical volumes.

• LVM allows for dynamic resizing of logical volumes without downtime.

• It provides features like snapshots, striping, mirroring, and thin provisioning.

• Physical volumes are divided into extents, which can be allocated to logical volumes.

• Commands like pvcreate, vgcreate, lvcreate are used to create physical volumes, volume groups, and logical volumes respectivel...read more