Top 35 Linux Networking Interview Questions With Answers 2023 PDF


Overall, mature open source tools bridge the interoperability gap for unified access control between Active Directory and Linux systems. Examples include implementing firewalls, setting up user authentication and access control, patching systems regularly, encrypting data, and monitoring logs. You should also explain how you use tools such as intrusion detection systems, vulnerability scanners, and network analyzers to ensure that your systems are secure. Finally, mention any experience you have with developing or deploying security policies or procedures.

  1. The first character of the permission string represents the file type (d for directory, – for regular file).
  2. This content has been made available for informational purposes only.
  3. As a developer or programmer, you’re expected to be able to explain the systems and processes you work with clearly and accurately.
  4. It is useful for monitoring network activity and diagnosing network issues.
  5. Instead, they have a defined delay before execution, typically measured in days.
  6. On the other hand, because it is simple to use and attractive, GUI is popular with casual users.

Scrutinize logs for error messages and timestamps, monitor system resources, and delve into the daemon’s source code to identify potential bugs. Implement additional logging for specific events to facilitate the debugging process. Troubleshooting a Linux machine that can’t connect to specific websites requires a systematic approach. Begin by checking network connectivity using ‘ping’ or ‘traceroute,’ examine DNS resolution with ‘nslookup’ or ‘dig,’ and review firewall settings. Test connections to other websites to isolate the issue and investigate potential DNS or routing problems, making necessary adjustments to network settings. To resolve “Disk quota exceeded” errors for a Linux user, utilize the ‘quota’ command to review the user’s quota limits.

The leftmost digit is for the user, the middle digit is for the user group and the rightmost digit is for all. Linux is released under the General Public License (General Public License). Any project released under GPL can be modified and edited by the end users. The success of Linux demonstrates the power of collaboration and the impact of the open-source philosophy on the world of technology. It serves as a prominent example of how a freely shared and community-driven project can become a fundamental part of modern computing. On August 25, 1991, a Finnish computer science student named Linus Torvalds first released it.

What are common causes of a Linux system running out of disk space?

The major functions of intrusion prevention systems are to identify malicious activity, collect information about this activity, report it, and attempt to block or stop it. IPS typically records information related to observed events, notifies security administrators of important observed events, and produces reports. Many IPS can also respond to a detected threat by attempting to prevent it from succeeding.

What is Shell in Linux?

A shell is a command-line interface that allows users to interact with the operating system. The init process is the first process linux networking interview questions started by the Linux kernel during boot-up. The ps command will list all the running processes along with the process id.

They use various response techniques, which involve the IPS stopping the attack itself, changing the security environment, or changing the attack’s content. Network Address Translation (NAT) is a technique used in networking to modify the source or destination IP address of packets as they pass through a router or firewall. NAT is often used in private networks to allow devices with private IP addresses to communicate with devices on the public Internet. Network bonding is typically used in high-availability environments, such as servers and network appliances, to ensure network connectivity and prevent network downtime. Network interfaces in Linux refer to the physical or virtual connections that enable communication between the Linux system and other devices on a network. Network interfaces can be Ethernet ports, wireless adapters, or virtual interfaces created by software.

Sun Microsystems created an operating system that was based on Linux. This command will print the count of the word “linux” in the “interview.txt” file. Virtual Desktop is a feature that allows users to use the desktop beyond the physical limits of the screen. Basically, Virtual Desktop creates a virtual screen to expand the limitation of the normal screen. For example, if you want to set the permission such that the user can read, write, and execute it and members of your group can read and execute it, and others may only read it.

Q26. How do you troubleshoot DHCP-related issues in Linux?

The /etc/resolv.conf is the config file used for the DNS server resolution process. This config file is used to specify the DNS server, set up the search directive for domains, and configure the resolver options. You can use the LVM to create the logical volume for easy storage management through various features like resizing, volume mirroring, and snapshots. LVM is a powerful utility for disk management where you need dynamic storage allocations. It is called mirroring, which allows you to create a complete copy of data on multiple disks.

This question allows the interviewer to gauge your technical knowledge and experience with Linux systems. When answering this question, you should walk the interviewer through the steps you would take to set up a new Linux server. Some of these steps may include installing the operating system, configuring security settings, setting up user accounts, and installing necessary software or applications. Be sure to mention any best practices that you follow when setting up a server as well as any troubleshooting techniques you use if something goes wrong.

Explain the basic features of the Linux OS.

ACLs allow specifying permissions for specific users or groups on a file or directory. The ‘setfacl’ and ‘getfacl’ commands are used to manage and display ACLs, providing finer-grained control over access permissions. It is used to load Linux into memory and start the operating system. LILO is customizable, i.e., if the default configuration is not correct, it can be changed.

Hence, init works as the parent process because its process ID is 1. Originally Linux systems used to have SysV init, but now it is developed as the systemd init (an improved version of SysV). It combines RAID 0 and RAID 1 to generate the set of mirror disks to improve performance and redundancy.

The sudoers file in Linux controls the sudo access permissions for users. It determines which users are allowed to run commands with superuser (root) privileges. To configure sudo access, you can edit the sudoers file using the visudo command. A daemon is a background process that runs independently of user sessions.

Confidentiality – means information is not disclosed to unauthorized individuals, entities, or processes. For example, if we say I have a password for my Gmail account but someone saw it while I was doing login into my Gmail account. In that case, my password has been compromised and Confidentiality has been breached. You should also apply system updates regularly, and use secure data storage solutions such as encryption.

Helpful scenarios include planning updates during low-traffic hours, staggering resource-intensive tasks, or automating notifications based on events. Overall, the at command gives administrators valuable control over one-off executions. Once ACLs are enabled, you can use commands like getfacl and setfacl to manage access control lists on files and directories within the /home partition. Since /proc contains virtual files, it is called a virtual file system.

A server farm is a set of many servers interconnected together and housed within the same physical facility. A server farm provides the combined computing power of many servers by simultaneously executing one or more applications or services. A server farm is generally a part of an enterprise data center or a component of a supercomputer. Networking refers to interconnected devices that can exchange data or information and can share resources. A Computer Network is a collection of interconnected computers that allows devices to communicate and exchange data using a communication medium. The ‘nslookup’ command is used to query the DNS (Domain Name System) servers to resolve a hostname to an IP address.