ABC Consultants System Engineer Interview Questions and Answers

To troubleshoot a server not able to login, check network connectivity, verify credentials, and review system logs.

• Check network connectivity to ensure the server is reachable

• Verify the correctness of login credentials

• Review system logs for any error messages or indications of login failures

• Restart the server if necessary

• Check for any recent system updates or changes that may have caused the login issue

To create swap for a Linux server, use the 'mkswap' command to create a swap file or partition and then activate it using the 'swapon' command.

• Use 'dd' command to create a swap file with desired size: 'dd if=/dev/zero of=/path/to/swapfile bs=1G count=4'

• Set the correct permissions for the swap file: 'chmod 600 /path/to/swapfile'

• Create swap space on the file: 'mkswap /path/to/swapfile'

• Activate the swap space: 'swapon /pa...read more

Tar utility is used to create backups by compressing files and directories.

• To create a backup using tar, use the 'tar' command followed by the appropriate options and arguments.

• Specify the files or directories to be included in the backup.

• Use the '-cvf' options to create a new tar archive file.

• Specify the name of the archive file to be created.

• To compress the backup, use the '-z' option for gzip compression or '-j' opt...read more

scp is a command-line tool used for securely transferring files between a local and remote Linux system.

• scp stands for secure copy.

• It uses SSH protocol for secure file transfer.

• It can be used to copy files between local and remote systems, or between two remote systems.

• Syntax: scp [options] [source] [destination]

• Example: scp file.txt user@remote:/path/to/destination

yum is a package manager that resolves dependencies and installs packages from repositories, while rpm is a low-level package manager that directly installs packages.

• yum is a high-level package manager that uses rpm as its underlying package management system.

• yum can automatically resolve dependencies and install packages from repositories, while rpm requires manual dependency resolution.

• yum can also update packages an...read more

To troubleshoot HTTPS not working, check certificate validity, firewall settings, and web server configuration.

• Check if the SSL/TLS certificate is valid and properly installed

• Verify if the web server is configured to listen on the correct HTTPS port (usually 443)

• Ensure that the firewall allows incoming connections on the HTTPS port

• Check if the SSL/TLS protocols and cipher suites are correctly configured

• Inspect the web ...read more

These are common network protocols used for communication and file transfer.

• SSH (Secure Shell) is a secure protocol used for remote login and secure file transfer.

• HTTP (Hypertext Transfer Protocol) is used for transmitting web pages and other resources over the internet.

• HTTPS (HTTP Secure) is the secure version of HTTP, encrypted with SSL/TLS.

• FTP (File Transfer Protocol) is used for transferring files between a client ...read more

UDP is a connectionless protocol that provides fast, but unreliable communication. TCP is a connection-oriented protocol that ensures reliable communication.

• UDP stands for User Datagram Protocol, while TCP stands for Transmission Control Protocol.

• UDP is faster than TCP because it does not establish a connection before sending data.

• UDP does not guarantee delivery of packets, while TCP ensures reliable delivery.

• TCP uses ...read more

The network layers for network are a hierarchical structure that defines the communication process between devices.

• The network layers are a way to organize and standardize the communication process in a network.

• There are several models that define the network layers, such as the OSI model and the TCP/IP model.

• Each layer has a specific function and interacts with the layers above and below it.

• The layers provide abstract...read more

Troubleshooting steps for not being able to login through putty

• Check network connectivity

• Verify correct IP address and port number

• Ensure SSH service is running on the server

• Check firewall settings

• Verify correct username and password

• Check if the server is reachable and not down

Yes, I am familiar with scripting in bash and sh.

• I have experience writing scripts in bash and sh.

• I am comfortable with using variables, loops, conditionals, and functions in bash and sh scripts.

• I have used bash and sh scripts for automating tasks, managing system configurations, and troubleshooting.

• I am familiar with common commands and utilities in bash and sh, such as grep, sed, awk, and find.

• I have written scripts ...read more