10+ NTT Data Network Engineer Interview Questions and Answers

Configuring FAILOVER via static Route involves setting up multiple routes with different priorities.

• Create multiple static routes with different next-hop IP addresses

• Assign different administrative distances to each static route

• Configure IP SLA to track the primary route and switch to the secondary route if the primary route fails

OSPF (Open Shortest Path First) is a routing protocol used to determine the best path for data packets in a network.

• OSPF is a link-state routing protocol that uses Dijkstra's algorithm to calculate the shortest path to each network.

• OSPF routers exchange Link State Advertisements (LSAs) to build a topology database.

• There are several types of LSAs, including Router LSAs, Network LSAs, Summary LSAs, and AS External LSAs.

• OSPF routers maintain neighbor relationships and exchange H...read more

LSA Types are used in OSPF to describe the type of information contained in the LSA.

• Type 1: Router LSA - contains information about the router and its directly connected networks

• Type 2: Network LSA - describes the networks connected to a multi-access network

• Type 3: Summary LSA - contains information about networks outside of the area

• Type 4: ASBR Summary LSA - describes the ASBR router to the rest of the OSPF domain

• Type 5: External LSA - contains information about external net...read more

BGP (Border Gateway Protocol) is a routing protocol used to exchange routing information between different autonomous systems.

• BGP has four main states: Idle, Connect, OpenSent, and Established.

• BGP attributes include AS_PATH, NEXT_HOP, LOCAL_PREF, and ORIGIN.

• AS_PATH attribute shows the path the route has taken through different autonomous systems.

• NEXT_HOP attribute specifies the next hop IP address to reach a particular destination.

• LOCAL_PREF attribute is used to influence out...read more

BGP attributes are used to determine the best path for routing traffic between autonomous systems.

• BGP attributes include: AS Path, Next Hop, Local Preference, Weight, Multi-Exit Discriminator (MED), Origin, and Community

• AS Path is a list of autonomous systems that the route has passed through

• Next Hop is the IP address of the next router in the path

• Local Preference is used to indicate the preferred path for outbound traffic

• Weight is a Cisco-specific attribute used to indicate ...read more

VLANs are created to segment network traffic, improve network performance, enhance security, and simplify network management.

• Segment network traffic to improve performance and reduce congestion

• Enhance security by isolating sensitive data or devices

• Simplify network management by grouping devices logically

• Allow for easier troubleshooting and maintenance

• Enable better control over broadcast domains

• Example: Creating separate VLANs for different departments in a company

Routers switch configuration and commands involve setting up and managing network devices for efficient data routing.

• Routers use commands like 'show ip route' to display routing table information

• Configuration involves setting up IP addresses, subnet masks, and default gateways

• Commands like 'show interfaces' can display interface status and configuration details

BGP (Border Gateway Protocol) is a routing protocol used to exchange routing information between different networks on the internet.

• BGP is used by internet service providers to make routing decisions.

• It operates on TCP port 179.

• BGP uses path attributes to determine the best route to a destination.

• BGP can be configured in different ways such as eBGP (external BGP) and iBGP (internal BGP).

VRRP stands for Virtual Router Redundancy Protocol, used to provide high availability for routers by creating a virtual IP address.

• VRRP allows multiple routers to work together in a group, with one router acting as the master and others as backups.

• If the master router fails, one of the backup routers takes over the virtual IP address to ensure continuous network connectivity.

• VRRP uses a priority value to determine which router becomes the master in case of a failure.

• Commonly ...read more

HSRP (Hot Standby Router Protocol) and VRRP (Virtual Router Redundancy Protocol) are network protocols used for providing high availability in routing.

• HSRP and VRRP are used to provide redundancy for routers in a network.

• They allow for automatic failover in case of a router failure.

• HSRP is a Cisco proprietary protocol, while VRRP is an open standard protocol.

• Both protocols use a virtual IP address that clients use as their default gateway.

• Example: In a network with multiple r...read more