100+ Network Administrator Interview Questions and Answers

Traffic inspection of checkpoint firewall involves analyzing network traffic for security purposes.

• Checkpoint firewall inspects traffic at the application layer to identify and block malicious traffic

• It uses various security mechanisms such as stateful inspection, deep packet inspection, and intrusion prevention system

• Traffic can be inspected based on source/destination IP, port, protocol, and content

• Logs are generated for all traffic events and can be analyzed for security i...read more

The colour code for normal network crimping is used to identify the correct order of wires in a network cable.

• The colour code for normal network crimping follows the T568B standard.

• The order of wires in a network cable is: white-orange, orange, white-green, blue, white-blue, green, white-brown, brown.

• This colour code is used for Ethernet cables, such as Cat5e or Cat6, to ensure proper connectivity.

Use the rand() function in C/C++ to generate random numbers.

• Include the header file for the rand() function

• Use srand() to seed the random number generator

• Generate random numbers using rand() function

IP stands for Internet Protocol, a set of rules governing the format of data sent over the internet. OSI layers refer to the Open Systems Interconnection model, a conceptual framework used to understand how different networking protocols interact.

• IP (Internet Protocol) is a set of rules that governs the format of data sent over the internet.

• OSI (Open Systems Interconnection) layers refer to a conceptual framework that helps understand how different networking protocols intera...read more

MPLS is a protocol used to route traffic within a network while BGP is used to route traffic between networks.

• MPLS is used to create virtual private networks (VPNs) within a network

• BGP is used to exchange routing information between different networks

• MPLS can be used in conjunction with BGP to provide end-to-end connectivity between networks

• Examples of MPLS-based VPNs include Layer 2 VPNs and Layer 3 VPNs

• BGP is commonly used in Internet Service Provider (ISP) networks to exch...read more

The implementation of a new device in a network involves planning, testing, and deployment to ensure seamless integration.

• Plan the implementation process, including assessing network compatibility and potential impact on existing devices.

• Test the new device in a controlled environment to identify any issues or conflicts before full deployment.

• Deploy the new device during off-peak hours to minimize disruption to network operations.

• Monitor the network after implementation to en...read more

A network is a group of interconnected devices that can communicate and share resources.

• Networks can be wired or wireless

• Devices on a network can include computers, printers, servers, and routers

• Networks can be local (LAN) or wide area (WAN)

• Networks can be used for sharing files, printers, and internet access

• Networks can be secured with firewalls, passwords, and encryption

A protocol is a set of rules that governs the communication between devices on a network.

• Protocols define the format, timing, sequencing, and error checking of messages exchanged between devices.

• Examples of protocols include TCP/IP, HTTP, FTP, SMTP, and DNS.

• Protocols can be implemented in hardware, software, or a combination of both.

• Different protocols are used for different purposes, such as data transfer, email, web browsing, and network management.

OSPF special area is a type of OSPF area that has a different behavior than other OSPF areas.

• OSPF special area includes stub area, totally stubby area, and not-so-stubby area (NSSA).

• In stub area, the area border router (ABR) summarizes external routes as a default route.

• In totally stubby area, the ABR summarizes all routes as a default route.

• In NSSA, external routes are allowed but are translated into internal routes.

• OSPF special area reduces the size of the routing table and...read more

Police creation on firewalls refers to the process of setting up rules and policies to monitor and control network traffic.

• Firewalls act as a barrier between a trusted internal network and an untrusted external network

• Police creation involves setting up rules to allow or block traffic based on specific criteria such as IP address, port number, and protocol

• Firewalls can also be configured to log and alert administrators of any suspicious activity

• Examples of firewall software i...read more

SLA base routing is a method of routing traffic based on service level agreements.

• SLA base routing prioritizes traffic based on the agreed-upon service level agreements.

• It ensures that critical traffic is given priority over less important traffic.

• SLA base routing can be used to ensure that certain applications or services receive the necessary bandwidth and resources.

• It can also be used to ensure that traffic is routed through the most efficient path to meet SLA requirements...read more

Subnetting involves dividing a network into smaller subnetworks for better management and security.

• Class A networks have a default subnet mask of 255.0.0.0 and can be subnetted to create smaller networks.

• Class C networks have a default subnet mask of 255.255.255.0 and can also be subnetted.

• Subnetting allows for better utilization of IP addresses and improves network performance.

• Subnetting also enhances network security by isolating different departments or functions within an...read more

Networking is the practice of connecting devices and systems to share resources and communicate with each other.

• Networking involves the use of hardware and software to create and manage connections between devices and systems.

• It enables the sharing of resources such as files, printers, and internet access.

• Networking protocols such as TCP/IP and DNS are used to facilitate communication between devices.

• Examples of networking technologies include Ethernet, Wi-Fi, and Bluetooth.

• N...read more

System problems in error refer to issues or errors that occur within a computer system.

• System problems can include hardware malfunctions, software bugs, network issues, and security breaches.

• Troubleshooting system problems often involves identifying the root cause of the issue and implementing a solution.

• Examples of system problems in error include blue screen errors, application crashes, slow performance, and connectivity issues.

BGP neighbors are configured to establish and maintain BGP sessions between routers.

• BGP neighbors are configured using the neighbor command in router configuration mode.

• The neighbor IP address and remote AS number must be specified.

• BGP neighbors must be directly connected or static routes must be configured.

• BGP sessions can be verified using the show ip bgp summary command.

• Troubleshooting BGP neighbor issues can involve checking network connectivity and verifying BGP configur...read more

IP stands for Internet Protocol, a set of rules governing the format of data sent over the internet or other networks.

• IP is responsible for routing data packets between devices on a network.

• It assigns unique addresses to each device on the network, known as IP addresses.

• There are two versions of IP in use today: IPv4 and IPv6.

• IPv4 addresses are 32-bit numbers, while IPv6 addresses are 128-bit numbers.

• IP is a layer 3 protocol in the OSI model.

• Examples of IP-based protocols inc...read more

DNS stands for Domain Name System, it translates domain names to IP addresses.

• DNS is like a phone book for the internet, translating domain names (like google.com) to IP addresses (like 172.217.3.206)

• DNS works by sending queries to DNS servers, which then look up the corresponding IP address for the requested domain

• DNS also helps with load balancing and redundancy by allowing multiple IP addresses to be associated with a single domain name

SNAT stands for Secure Network Address Translation and is a feature in F5 that allows for the translation of IP addresses.

• SNAT is used to translate the source IP address of outgoing traffic to a different IP address.

• This can be useful in scenarios where multiple devices are sharing a single public IP address.

• SNAT can also be used to improve security by hiding the actual IP address of a device from the public internet.

• F5 offers a variety of SNAT options, including automap SNAT...read more

A channel is a medium through which data is transmitted from one device to another.

• Channels can be physical, such as copper wires or fiber optic cables, or wireless, such as radio waves or infrared signals.

• Different channels have different bandwidths, which affect the speed and amount of data that can be transmitted.

• Examples of channels include Ethernet, Wi-Fi, Bluetooth, and cellular networks.

VDOM is a virtual domain feature in Fortigate Firewall that allows multiple virtual firewalls to be created on a single physical device.

• VDOM provides separate security policies, interfaces, routing tables, and administrators for each virtual firewall.

• It helps in reducing hardware costs and simplifying network management.

• Each VDOM has its own set of interfaces, security policies, routing tables, and administrators.

• VDOMs can be used to create separate virtual firewalls for diff...read more

Routing & switching are networking concepts that involve directing data packets to their destination and connecting devices within a network.

• Routing involves determining the best path for data packets to travel from one network to another.

• Switching involves connecting devices within the same network based on MAC addresses.

• Routers are used for routing data packets between different networks.

• Switches are used for connecting devices within the same network.

• Routing protocols like...read more

ACL can be configured by defining rules to permit or deny traffic based on source/destination IP, port, and protocol.

• Identify the traffic that needs to be controlled

• Define the rules for permitting or denying traffic

• Apply the ACL to the appropriate interface or VLAN

• Regularly review and update the ACL to ensure it meets the changing needs of the network

VLANs can be configured using switch management interfaces or command line interfaces.

• Identify the VLANs needed and assign them a VLAN ID

• Configure the switch ports to be members of the appropriate VLAN

• Configure the VLAN interfaces on the switch

• Configure VLAN trunking protocol (VTP) if necessary

• Verify the VLAN configuration using show commands

BGP and OSPF are routing protocols used in networking to determine the best path for data to travel between networks.

• BGP (Border Gateway Protocol) is an exterior gateway protocol used to exchange routing information between different autonomous systems.

• OSPF (Open Shortest Path First) is an interior gateway protocol used to find the shortest path for routing within a single autonomous system.

• Routing protocols like BGP and OSPF help routers make decisions on how to forward pack...read more

A system administrator is responsible for managing and maintaining computer systems and networks.

• Installing and configuring software and hardware

• Monitoring system performance and troubleshooting issues

• Managing user accounts and permissions

• Backing up and restoring data

• Ensuring system security and implementing security measures

• Updating and upgrading systems

• Documenting system configurations and procedures

A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

• Firewalls can be hardware or software-based

• They can be configured to block or allow traffic based on IP addresses, ports, protocols, and other criteria

• Firewalls can be set up to create a DMZ (demilitarized zone) to separate public-facing servers from internal networks

• Examples of firewall software include Windows Firewall, iptables, and...read more

SD-WAN technology is a software-defined approach to managing wide area networks, allowing for centralized control and automation.

• SD-WAN uses software to dynamically route traffic across the network based on real-time conditions.

• It can prioritize critical applications and optimize performance by utilizing multiple connection types.

• SD-WAN simplifies network management and reduces costs by replacing expensive MPLS connections with cheaper broadband links.

• It provides visibility i...read more

BGP stands for Border Gateway Protocol. It is a routing protocol used to exchange routing information between different networks.

• BGP is used to connect different autonomous systems (AS) on the internet.

• It is a path-vector protocol that selects the best path for data to travel based on various attributes.

• BGP is commonly used by internet service providers (ISPs) to connect their networks to the internet.

• It is also used in large enterprise networks to connect multiple locations....read more

DDoS stands for Distributed Denial of Service, a type of cyber attack that floods a network or website with traffic to make it unavailable.

• DDoS attacks are carried out by multiple compromised systems, often called a botnet.

• The goal of a DDoS attack is to overwhelm the target with traffic, making it impossible for legitimate users to access the service.

• DDoS attacks can be mitigated by using specialized hardware or software, or by working with a content delivery network (CDN).

• E...read more

Loc Perf is not a commonly known term in the field of Network Administration.

• There is no widely accepted definition or explanation for Loc Perf in the context of Network Administration.

• It is possible that the term is specific to a particular organization or system.

• Without more information or context, it is difficult to provide a meaningful answer to this question.

MPLS (Multiprotocol Label Switching) is a protocol for efficient packet forwarding in a network.

• MPLS is used to improve the speed and performance of network traffic.

• It operates at the data link layer and uses labels to direct packets along predetermined paths.

• MPLS can be used to create virtual private networks (VPNs) and prioritize traffic based on quality of service (QoS).

• It allows for traffic engineering, enabling network administrators to control the flow of data.

• Example: ...read more

VPN stands for Virtual Private Network. Protocols are rules that govern data transmission over a network.

• VPN allows users to securely access a private network over a public network like the internet

• Protocols are sets of rules that determine how data is transmitted between devices

• Common VPN protocols include OpenVPN, L2TP/IPsec, and PPTP

A route map is a set of rules that determine how traffic is routed between networks.

• Route maps are used in network routing protocols to control the flow of traffic.

• They can be used to filter routes, set metrics, and modify attributes of routes.

• Route maps are made up of match and set statements that define the conditions and actions to be taken.

• For example, a route map could be used to prioritize traffic from a certain network over others.

• Route maps are commonly used in Cisco ...read more

STP stands for Spanning Tree Protocol. It is a network protocol used to prevent loops in Ethernet networks.

• STP is used to create a loop-free logical topology in a network.

• It works by selecting a root bridge and calculating the shortest path to reach each network segment.

• STP uses a tree-like structure to block redundant paths and prevent broadcast storms.

• It helps ensure network stability and prevents network congestion.

• STP is defined by the IEEE 802.1D standard.

TCP/IP is a set of protocols used for communication between devices on a network.

• TCP (Transmission Control Protocol) is responsible for establishing and maintaining a connection between devices.

• IP (Internet Protocol) is responsible for routing data packets between devices on a network.

• TCP/IP is the foundation of the internet and allows devices to communicate with each other.

• Examples of TCP/IP applications include web browsing, email, and file transfer.

Switch and router configuration involves setting up network devices to ensure proper communication and data transfer.

• Configure VLANs on switches to segment network traffic

• Set up routing protocols on routers to enable communication between different networks

• Implement access control lists (ACLs) on routers to control traffic flow

• Enable DHCP services on routers to automatically assign IP addresses to devices

• Configure NAT on routers to allow devices with private IP addresses to a...read more

The OSI model is a conceptual framework used to describe the communication functions of a network.

• The model has 7 layers, each with a specific function.

• The layers are: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Each layer communicates with the layer above and below it.

• The model helps ensure interoperability between different network devices and software.

• Example: When you visit a website, the Application layer sends a request to the Transpo...read more

DDoS attack is a malicious attempt to disrupt normal traffic of a targeted server, service, or network by overwhelming it with a flood of internet traffic.

• DDoS stands for Distributed Denial of Service

• Attackers use multiple compromised systems to flood the target with traffic

• Goal is to make the target unavailable to its users

• Common types include UDP flood, SYN flood, and HTTP flood

• Mitigation techniques include using firewalls, load balancers, and DDoS protection services

The OSI model is a conceptual framework for understanding network communication.

• The OSI model has 7 layers, each with a specific function.

• The layers are: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Each layer communicates with the layer above and below it.

• The model helps ensure interoperability between different network devices and software.

• Example: HTTP operates at the Application layer, while TCP operates at the Transport layer.

ACL stands for Access Control List, which is a set of rules that controls network traffic and permissions on a network device.

• ACL is used to filter network traffic based on defined criteria such as source or destination IP address, port number, protocol, etc.

• ACL can be configured on routers, switches, firewalls, and other network devices to control access to resources.

• There are two types of ACLs: standard ACLs and extended ACLs.

• Example: In a router configuration, an ACL can b...read more

Switching is the process of forwarding data packets between devices on a network based on the destination address.

• Switching occurs at the data link layer of the OSI model.

• Switches use MAC addresses to determine where to forward incoming data packets.

• Switching is faster and more efficient than traditional hub-based networking.

• Examples of switches include Cisco Catalyst series and Juniper EX series.

STP (Spanning Tree Protocol) processes are used to prevent network loops and ensure redundancy in a network.

• STP elects a root bridge to be the central point of the network.

• STP blocks redundant links to prevent loops.

• STP uses BPDU (Bridge Protocol Data Unit) messages to communicate between switches.

• STP has different port states: blocking, listening, learning, forwarding, and disabled.

• STP can be configured with different versions such as STP, RSTP, and MSTP.

The OSI (Open Systems Interconnection) model is a conceptual framework that standardizes the functions of a communication system into seven layers.

• The OSI model is used to understand and describe how different network protocols and technologies interact with each other.

• Each layer in the OSI model has a specific function and communicates with the adjacent layers.

• The seven layers of the OSI model are: Physical, Data Link, Network, Transport, Session, Presentation, and Applicati...read more

As a Network Administrator, my daily work routine involves managing and maintaining network infrastructure, troubleshooting network issues, and implementing security measures.

• Monitoring network performance and ensuring its availability

• Configuring and maintaining network equipment such as routers, switches, and firewalls

• Troubleshooting network issues and resolving connectivity problems

• Implementing security measures to protect the network from unauthorized access

• Managing user a...read more

DHCP assigns IP addresses to devices on a network automatically

• DHCP server assigns IP addresses to devices on the network

• DHCP clients request IP addresses from the DHCP server

• DHCP uses a lease mechanism to manage IP address assignments

• DHCP reduces the administrative burden of manually assigning IP addresses

DNS is a system that translates domain names to IP addresses to locate resources on the internet.

• DNS resolves domain names to IP addresses

• DNS operates through a distributed database system

• DNS uses hierarchical structure with top-level domains like .com, .org, etc.

• DNS queries are resolved through recursive and iterative processes

L3 switches are network devices that operate at the network layer of the OSI model, providing routing functionality along with switching capabilities.

• L3 switches can route traffic based on IP addresses, making them more intelligent than L2 switches.

• They can support VLANs and provide inter-VLAN routing.

• L3 switches are commonly used in enterprise networks to improve network performance and security.

• Examples of L3 switches include Cisco Catalyst 3850 and Juniper EX Series.