From unforeseen outages to performance degradation, all is managed by network fault management. It is mainly seeing the network and maintaining it to save it from mistakes and faults. The troubleshooting starts from the first level and is done under a process. Some of the tools used for troubleshooting are ping, Tracert, ipconfig, and many more. The most basic network problem is the router issue. It can be easily resolved by restarting at that time or quick restarts in a while. We will discuss Networking Troubleshooting Interview Questions here in this article for you.
Networking Troubleshooting Interview Questions
- Define backbone network.
A design to distribute data and different routes to various networks which is a centralized infrastructure is known as a backbone network.
- What is a LAN?
The network connection between two or more networks or computers placed physically close to each other is called a LAN. It stands for local area network. There are two types of LAN:
- Client-server LAN: In this, a LAN is set up between a server and many different clients. The server has all the information which is passed to the clients.
- Peer to peer LAN: In this LAN, all computers are treated equally connected in a network. No computer is on a higher or a lower level.
- Define data encapsulation.
The transmission of smaller manageable chunks of big data across a network is done through data encapsulation. The header in this process contains the source and destination address along with the parity check. The implementation details of this mechanism are hidden to the user of a class. By executing special functions, a restricted set of operations can be performed on the hidden members of the class. These special functions are known as methods.
- Define network topology along with its types.
In a communication network, the arrangement of the elements is defined by the network topology. In simpler terms, it defines how the physical arrangement is made along with its connection. There are various types of topologies, but some of them are more common and listed below:
- Star topology refers to a connection in which all systems are connected to the central hub via physical cables independently, which causes it to look like a star. The central hub receives all the data that has to be shared. The main benefit of using this topology is that others will remain up and run without a problem, even if a system goes down. However, the main disadvantage is that if the central system fails, all other devices will stop running.
- Bus topology is also known as line topology for backbone topology. A single cable is used to connect all devices which run in one direction. The data follows the same direction of transmission. The benefit of using this topology is its strengths and cost-effectiveness due to the requirement of the limited source. This is also used because more nodes can be added by joining cables. The biggest disadvantage of this topology is that failure is higher because if the cable fails, all systems shut down.
- Ring topology creates a ring of all its featured nodes. The data passes all through all nodes before it reaches its destination in any direction. The benefit of using this topology is that only one node can send information, reducing the chances of packet loss. The disadvantage of this topology is that if one node fails, the whole network will shut down. The topic of scalability comes into account due to its lower bandwidth.
- Tree topology comprises a central device at the top followed by a hatchery of additional devices. The addition of notes is easier because it takes the best of the bus and ring topology. The benefit of using this technology is that even if the hub fails, the branches will remain to have their connectivity. Although it solves scalability, it is hard to manage due to the cost of cabling the whole system.
- Mesh topology, like its name, forms a web-like structure of interconnected nodes. Transmission of each data packet becomes easier and efficient by using liberal logic, which tells the best path. The benefit of using this topology is the fact that it is reliable and failure resistant. The main disadvantage of this topology is the technological error that sometimes occurs due to data flooding, and all the notes receive the data without logic. They also require numerous cables And Labour intensive work to set up.
- Hybrid topology combines the features of two or more topologies to meet the network demands. The main use of this topology is done at big companies where there is a bifurcation of many departments due to its flexibility. The complexity of this topology makes it difficult to handle and requires experience.
- Define the process of network troubleshooting.
In a network, the issues arise at different points. To solve a problem, you must know the cause and place of the network. We need to gather the correct information like the origin, the kind, and the amount of time it has been going on for this. The process of doing so is given as follows:
- Hardware Check: Firstly, the hardware should be checked to make sure that connections, turned on and working. Sometimes the problem might be as small as the cord loose, router shut down, or cord plugged out, and in these cases, there is no need for network troubleshooting. Some other basic steps can be followed for troubleshooting network hardware. Maybe the problem can be easily solved by switching on and off or keeping the device off for sixty seconds. Power cycling is also an effective step to do so.
- Ipconfig: In the command prompt, type ipconfig and into the terminal. You may get your default gateway and IP address, and when it starts from 169, it is not getting a proper IP address. Try “ipconfig/renew” and request a new one which solves the problem in some cases. Otherwise, use an ethernet cable, and if you get your IP address, then the problem is in the router rather than the network.
- Ping and Tracert: If the IP address is fine without ethernet, maybe the problem is between your router and the internet. This is the time to use ping by which you send a ping to larger servers like google to check if they can connect to your router. If this fails to connect to your router, then maybe there is a problem. You can also use tracert to track the problem as it hops between your router and googles DNS. We can see the exact location of the problem, and if the error comes early, then the problem may be in your Local Network.
- DNS Check: Use nslookup to check if there is a problem with the server you are using. If the words like “timed out,” “service failure,” “refused,” or “network are unreachable” appear on the screen, then the problem is with the DNS and not your network.
- ISP Contact: For any problems related to the internet service, contact your internet service provider. Maybe there is a problem from their side. You can also check if other people have the same problems by searching outage maps and related information on the mobile apps.
- Virus and Malware Check: Check if something is not stopping some programs to network to run properly. This may be because your antivirus software is not working properly or the network has problems that are blocked by it.
- Database Logs: Maybe your database is not working properly and checks for the problems. It might be that it is not functioning as expected and cousin the problems to flow on, henceforth causing the network to slow down.
- Can you explain the need to use a VPN?
To establish a secure connection between you and the internet, a VPN is used. VPN stands for Virtual Private Network. By using a VPN, a person can go incognito, or the IP address is hidden, and a person becomes anonymous. There are three types of VPN:
- SSL VPN: Most people are provided with a company laptop to work with appropriate technology. But during the crisis, it was not possible to give the new joiners. So the companies started to use SSL VPN, which is generally implemented through a hardware box. The prerequisite is HTML5 support, and an HTML page browser is there, which is secured by username and password.
- Site-to-site VPN: They are mostly private networks that are secured from authorization from other parties. They are used when companies have different bases with their local network. The resources of each other can be accessed with anonymity. They are complex and not flexible but most adequate for usage in large companies with many departments.
- Client- to- server VPN: The computers are connected to a client, and a connection must be set up. This may be explained like your home PC connected to your office with all resources and client servers. This will look like working at home as an office. The user is not connected to their ISP, but the hosts and a secure tunnel are not made, but the VPN only sends encrypted data.
- What is NAT?
The NAT protocol is followed to share a single connection to the internet for computers connected on a common network. NAT stands for Network Address Translation.
- Can you give the full form of RIP and explain it in brief?
Yes. RIP stands for Routing Information Protocol. This is used to send data over the networks via a router. This is done by broadcasting the router table to all other routers in the network and managing it. The distance of networks is given in terms of hops.
- Define NIC.
For connecting to a network, every PC is attached with a NIC. MAC address is unique for every NIC, which helps in identifying a computer over a network. The full form of NIC is Network Interface Card.
- Give the names of layers under the TCP/IP.
There are 4 different types of layers which are as below:
- Transport layer
- Network layer
- Internet layer
- Application layer
- Define NOS and DoS.
NOS: It stands for Network operating system, which helps provide network connectivity to a computer to interact with other computers and connected devices.
DoS: A denial of service attack is made to abruptly stop using the internet or any other network by the user. A group of perpetrators does this. The easiest way to do so is to overload the server so that the server has to reset.
Anyone can use network troubleshooting to earn money or simply helping themselves. It is better to know some basic tips so that no one can cheat you. There are several questions in this article, but more information should be learned before an interview.
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