10+ HCL Group Linux Administrator Interview Questions and Answers

To check logs at a particular time and send a report to the client, use the 'grep' command and a cron job.

• Use the 'grep' command to search for logs at a specific time.

• Create a cron job to run the 'grep' command at the desired time.

• Use a script to format the log data and send it to the client.

• Consider using a tool like Logwatch or Logrotate for automated log management.

Links are pointers to files or directories. Linux permissions control access to files and directories.

• Links can be hard links or symbolic links

• Hard links point directly to the file's inode

• Symbolic links point to the file's path

• Linux permissions are divided into three categories: owner, group, and others

• Each category has three types of permissions: read, write, and execute

• Permissions can be set using chmod command

Linux is an open-source operating system based on Unix. Unix is a family of multitasking, multiuser computer operating systems.

• Linux is open-source and free to use, while Unix is proprietary and usually requires a license.

• Linux has a larger community and more distributions (e.g. Ubuntu, CentOS), while Unix has fewer variations (e.g. Solaris, AIX).

• Linux is more customizable and can run on a wider range of hardware, while Unix is more stable and secure.

• Linux uses the GNU Genera...read more

Linux is an open-source operating system based on Unix. Its components include kernel, shell, GUI, utilities, and applications.

• Kernel: manages hardware resources and provides services to other system components

• Shell: provides a command-line interface for users to interact with the system

• GUI: provides a graphical interface for users to interact with the system

• Utilities: perform various system tasks such as file management, networking, and security

• Applications: software program...read more

Rollback patching is a process of reverting a patch or update to a previous version.

• Rollback patching is useful when a patch or update causes issues or conflicts with the system.

• It involves undoing the changes made by the patch or update and restoring the system to its previous state.

• Rollback patching can be done manually or automatically depending on the system and the patching process.

• Examples of rollback patching tools include Windows System Restore and Linux's yum history...read more

To create a repository, you need to choose a package manager and create a configuration file.

• Choose a package manager like YUM or APT

• Create a configuration file with repository details

• Add packages to the repository

• Sign the repository to ensure package integrity

• Publish the repository for others to use

To check prod servers, use monitoring tools, log files, performance metrics, and manual checks.

• Use monitoring tools like Nagios, Zabbix, or Prometheus to track server health and performance.

• Check log files for any errors or warnings that could indicate issues on the prod servers.

• Monitor performance metrics such as CPU usage, memory usage, disk space, and network traffic.

• Perform manual checks on critical services and applications running on the prod servers to ensure they are ...read more

To schedule a cron job, use the crontab command to edit the cron table file.

• Use the crontab -e command to open the cron table file for editing

• Add a new line to the file with the schedule timing and the command to be executed

• Save and exit the file to schedule the cron job

Sticky bit is a permission in Unix/Linux that allows only the owner of a file to delete or rename it.

• Sticky bit is represented by a 't' in the permissions of a file or directory.

• When the sticky bit is set on a directory, only the owner of a file within that directory can delete or rename the file.

• Commonly used on directories like /tmp to prevent users from deleting each other's files.

• Example: chmod +t directory_name