CCNA Interview Questions And Answers
CCNA INTERVIEW QUESTIONS AND ANSWERS
Here are the list of most frequently asked CCNA Interview Questions and Answers in technical interviews. These questions and answers are suitable for both freshers and experienced professionals at any level. The questions are for intermediate to somewhat advanced Networking professionals, but even if you are just a beginner or fresher you should be able to understand the answers and explanations here we give.
Best CCNA Interview Questions and Answers
CCNA Interview Questions and Answers for beginners and experts. List of frequently asked CCNA Interview Questions with answers by Besant Technologies.
We hope these CCNA interview questions and answers are useful and will help you to get the best job in the networking industry. This CCNA interview questions and answers are prepared by CCNA Professionals based on MNC Companies expectation. Stay tune we will update New CCNA Interview questions with Answers Frequently. If you want to learn Practical CCNA Training then please go through this CCNA Training in Chennai & CCNA Training in Bangalore.
CCNA Interview Questions and Answers for the Job Placements
Besant Technologies supports the students by providing CCNA interview questions and answers for the job placements and job purposes. CCNA is the leading important course in the present situation because more job openings and the high salary pay for this CCNA and more related jobs. We provide the CCNA online training also for all students around the world through the Gangboard medium. These are top CCNA interview questions and answers, prepared by our institute experienced trainers.
Here are the list of most frequently asked CCNA Interview Questions and Answers in technical interviews. These questions and answers are suitable for both freshers and experienced professionals at any level. The questions are for intermediate to somewhat advanced CCNA® professionals, but even if you are just a beginner or fresher you should be able to understand the answers and explanations here we give.
Need to check the reachability between to devices and check OSPF configuration whether all parameters are same and check neighbor is forced at both the end then fix the issue.
STP will prevent loop in the network. But it ill goes through 4 states to prevent a loop.RSTP is an evolution of STP to prevent looping in the network.it ill take 3 states. It is a fast convergence protocol
Prefixes coming from the neighbor router are exceeded so need to increase the maximum prefix in BGP neighbor.
In STP and RSTP if one port fails we can have redundancy but can’t do load balancing and can’t have efficient bandwidth we can accomplish these things in EtherChannel.
Needs to do BGP soft clear, It gets a new update from a neighbor.
No, since it’s a cisco property.
HSRP is for gateway redundancy, One will be active another one will be in standby mode. Once active more router fails standby becomes active. Again the active router coming up it will not be an inactive state. In order to make that, we need to enable preemption.
DHCP server is providing IP address to the client in this case after receiving IP from DHCP server host will send the Gratitude ARP message to all clients to find the conflict any reply receiving for G-ARP request host will not use that IP. This is called DAD process.
lowest cost to reach root bridge
lowest sender bridge id
lowest on bridge id
lowest sender port id
Enable secret
Two switches (sw1 and sw2)are connected via access port one end is connected to VLAN 10 of sw1 other end is connected to VLAN 20 of sw2 when host connected to VLAN 10 is sending traffic it will be received by VLAN 20 connected port of sw2.so sw2 checks the mac table received port belongs to vlan20 so it will send traffic to VLAN 20 connected hosts.
192.168.1.0/25 if those systems need to access internet service which type of NAT needs to be used.
NAT with PAT
Main difference is editing is possible in named ACL by having a sequence number.
Yes, it will form neighbourship hello and hold no need to be same for eigrp.
Router 1 advertise 10n/w as 10.0.0.0 n/w as 10.0.0.0/8 since Auto summary is disabled by default in EIGRP so it can’t understand the subnets. Needs to enable No-Auto summary.
Eigrp sends hello message once the segment configured under eigrp configuration. If hello messages exchanged only then eigrp will form neighborship and routing update will happen.
Change the domain name or delete vlan.dat file.
If old switch having higher CR number but no VLAN in that database it will be synchronized to all vtp clients. In order to avoid that we need to make the CR number
zero while connecting an old switch to existing network.
round robin
internal BGP, External BGP
IBGP: Within as we use IBGP AD-200
EBGP: between as we use EBGP AD-20
Access port is to carry single VLAN traffic
Trunk port is to carry all the VLAN traffic
10.0.0.9/24
10.0.0.10/25
yes since network address is same for both the hosts when it was doing ANDING process
Deny
Duplex, Speed, VLAN membership, native VLAN, allowed VLAN, trunking encapsulation protocol
Cisco proprietary, ISL supports a maximum of 1000 VLANs on a trunk port
Open std,802.1Q supports a maximum of 4096 VLANs on a trunk port.
bridge priority and Base ethernet
yes since we have only one area and also the same area
No entry
10.0.0.0/22 via gi0/2
if a packet with destination IP 10.0.0.1 is reaching the router what action router will do
send via gi0/2 since best match
179
127.0.0.1 Is The Loop Address For Local Testing Purpose
Open System Interconnection
Segment Fragmentation
Numbering Segment
Multi Tasking
Flow Control
Dynamic Host Configuration Protocol
It Has Dora Concept
Staright Cable
Cross Cable
CDP IS Cisco Discovery Protocol
Static Route And Dynamic Route
It Is The Protocol Send Periodic Updates Of Every 30 Sec
AD=120
AD=110
It Is The Process To Use Hardware Of Mac Address To Understand
Access Port
Trunk Port
Vitual Trunk Protocol
Server Mode
Client Mode
Transparent Mode
STP – Spanning Tree Protocol To Understand The Loop Address
Extended Unique Identifier
Access list control is list of commands used in filter the packets in router
Standard
Extended
Named
Frame relay is the packet switching technology..using for two or more routers with single interface
Local management interface
PAP- Password Authentication Protocol
CHAP – Challenge Handshake Authencation Protocol
Show run/show running-config
Show start/show start-config
Automatic Private IP Addressing .Ranges=169.254.0.1 TO 169.255.255.254
It is using for popular server to store the log files
NTP– network time protocol?
This is network management application
Running inside management service
MIB (management information base)
OSPF-Open shortest path first
Secondly routing tables is populated
Authentication
Encryption
Message integrity
Highest priority
Highest router id
Highest IP address
It is used to protect the switch port using port fast.
Disabled
Blocking
Listening
Learning
Forwarding
PAGP –port aggregation protocol
LACP – link aggregation protocol
Passive mode
Active mode
Namely-auto
Desirable
HSRP-Hot standby router protocol
VLSM-Variable length subnet mask
The subnet mask is 255.255.255.240
IPV6- unicasting routing
To find which routing protocol is trusted
Intra site automatic tunnel addressing protocol
Enhance Interior Gateway Protocol
When two user trying to use same bandwith .
Windows refer tp the number of segments that allowed to the destination
Local area network to be with private network
NVRAM
DRAM
Flash memory
It is the protocol to boot diskless workstations connect to the network.
This is the ethernet to makes use of fibre optic cables in the main transmission medium
Maximum Transmission Control Unit
Multi-Protocol Layer Switch is a technology or protocol for transmitting data between two or more locations.
DCE – Data Communication Equipment
DTE – Data Terminal Equipment
VPN is the extension of a private network that includes links across shared or public networks, such as the Internet. 5
OSPF (Open Shortest Path First) is a router protocol use to find the shortest path first.
NVRAM (Non Volatile Memory) – stores the start-up configuration file for the router.
Dynamic Host Configuration Protocol (DHCP) is a client-server protocol that automatically provides ip for the devices.
Interior Gateway Routing Protocol (IGRP) is a distance vector interior gateway protocol developed by cisco.
Light Weight Directory Access Protocol(LDAP) is a software protocol for enabling anyone to locate any organizations.
Internet Control Message Protocol (ICMP)
Physical Topology
Trace route is a computer network diagnostic tool for displaying the route and measuring transit delays of packets across the internet protocol network.
Domain Name System(DNS) has different zone levels:
i. TLD Zones
ii. Domain Zones
iii. DNS Zones Types
iv. DNS Zone Records
v. Zone File Types
Maximum length a CAT-6 cable is support within 100 meters.
Speed of fast Ethernet is 10 Megabits per second.
Speed of fast Ethernet is 10 Megabits per second. Speed of Serial port
Port forwarding or port mapping is using for red directs the network address translation (NAT) .
Twisted pair co-axial fibre cables that are used in tree topology
Frame Relay is a high performance WAN protocol that operates at the physical and data link layers of OSI model.
By default Cisco routers have three levels of mode – zero, user and privilege
Multi-vlan has to understand using by trunk protocol.
A subnet-work or subnet is a logical subdivision of IP network.
A physical topology is interconnected between the wires and cables. The logical topology is the way information flows on the network.
The network that address would be 172.168.0.0 (172.168.0.1 is the first usable Difference between static IP and dynamic IP
Open Shortest Path First (OSPF) using by Dijkstra’s Algorithm
Sender Policy Framework (SPF) using for Email validation protocol.
MTU -Maximum Transmission unit need to match
NVRAM – is using for start-up and configuration
The Open Shortest Path First Protocol (OSPF)
DR means Designated route table of OSPF.
TCP -Transmission control protocol -connection oriented
UDP -User datagram protocol -connection-less
UDP port no is 15
TCP will send the acknowledgement for Sender and Receiver.
Interior gateway routing protocol
It has DORA CONCEPT
D- discovery
O- Offer
R- Request
A- Acknowlegement
Subnets means Small network into Large Network. Or Large network into small network.
This Directory system Agent by default TCP and UDP.
Port is 389
Port is 636
A link is a logical or physical component of a network. It will be data link layer.
A node is the name suggests to the connection of point on the network.
LLC stands for logical link control.. ising for optional services
to the application developer.
Latency is the amount of time delay.
In cut through as soon as the router receives the data frame. it will immediately receive and forward to the next segments.
- IPv4
- 32 bit address
- IPv6
- 128 bit address.
For local testing purposes and loopback address ip 127.0.0.1 is used
Loopback- looping to our individual systems, checking our individual systems. It is used to test TCP/IP stack is correctly installed.
Open System Interconnection (OSI) layers.
- It is a set of rules used to describe how to make networks.
- Whenever new network / hardware device, have to follow OSI reference model.
- There are 7layers, which means seven set of rules, they are designed by .
- It tells what are the ports /services /applications used.
- Flow control
- Multi-tasking
- Windowing
- Segment fragmentation
- Numbering segmenting
- Reliable and unreliable data delivery
- Error detection & error correction
Data encapsulation means, Data is sent from a higher layer to lower layer, each layer adds some information to the original data.The information added is called as header.
Data de-encapsulation means,Data is sent from lower layer to higher layer, each layer will remove information from the other layer.
Pocket Switching: all incoming data is switched to packets. It deals only with packets
Pocket Filtering: router sends and receives only packets. It is used in WAN,
Internetwork communication: joining of two or more networks.
Path selection: router is used to find the shortest and best path from source to destination.
Quality of Service: It is the ability of the n/w to provide better or special service to a set of users or applications.
- DHCP is a dynamic host configuration protocol.
- It allows devices to acquire their addressing information dynamically.
- It is based on bootstrap protocol .
- It is built on a server/client model and defines two components.
Registry key used for normal mode : 0x2102 to 0x210f.
Recover password use the registry key 0x2142.
- CDP – Cisco discovery protocol
- It has layer 2 protocol
- CDPworks based on mac addresses.(h/w addresses)
- It is used to find adjacent Cisco devices.
- It is a Cisco proprietary protocol means used to find only the neighboring Cisco devices.
It is used to find out
- IP addresses
- Port numbers
- iOS details
- Router models
- Switch models
- Interface details
- Device ID- hostname
There Two Types
- Staic
- Dynamic
Distance Vector Protocols send intermittent updates each every 30 sec or at some time interval to the adjacent routers. In case if there is a link failure instantly, they inform to update only after 30 secs. EX, RIP routing information protocol is a distance vector protocol.
The administrative distance for
- RIP: 120.
- EIGRP: 90
- OSPF: 110
Switching is the process of using the mac address/ hardware address of devices on a LAN to segment a Network. Switches break up large crash domains into smaller ones and that a crash domain is a Network segment with two or more devices sharing the similar bandwidth.
- VLAN – logical and arranged alignment of network users and resources.
- VLAN- connected to ports on a switch which are administratively defined.
- It is used to segment large networks and connect with routers for security purposes.
- For joining virtual VLANs or two different networks, we need routers.
If there is no VLAN in switches, it leads to a broadcast storm, and all ports will start broadcasting.
- Access port
- Trunk port
VTP means VLAN trunking protocol. This VTP is used to permit VLAN information to be automatically propagated through the switching environment.
The modes in VTP is Given below :
- Server mode
- Client mode
- Transparent mode
STP stands Spanning Tree Protocol, it was created by digital equipment corporation. It was created by IEEE which is 802.1d.
- IPv6 Have 128 bits with 8 groups. It has network part and host part. Each group have 16 bits.
- So 8X16=128, it is in hexadecimal format (00FF). There are 32 hexadecimal numbers.
- Each group (4 hex digits) is separated by colon.
- OSPF (IPv4)=224.0.0.5,224.0.0.6
- RIP (IPv4)=224.0.0.9
- EIGRP(IPv4)=224.0.0.10
- OSPF(IPv6)=ff02::5/ff02::6
- RIPng(IPv6)=ff02::9
- EIGRP(IPv6)=ff02::10
EUI means Extended Unique Identifier. It is an interface ID, which is typically Designed of mac addresses. We can create a EUI 64 interface in a 48 bit mac address by inserting the 0XFFFE between the upper three bytes and lower three bytes of the mac address.
- GUA are IPv6 public addresses, which can be used globally as public addresses and are unique in nature, e.g. 2000::1, 3001::1
- Address which start with hex 2 or 3.
- Ether Channels can be converted between two switches to provide some dynamic link configuration. Two protocols are accessible to convert bundled links in catalyst switches- PAgP (Port Aggregation Protocol), LACP (Link Aggregation Control Protocol).
- PAgP can be used only in Cisco devices but LACP can be used in other vendors also.
- There are two modes of LACP
- passive mode
- active mode.
- There are two modes of PAGP
- Namely Auto
There are Seven Layers in OSI Model
- Layer 7- Application Layer
- Layer 6- Presentation Layer
- Layer 5- Session Layer
- Layer 4- Transport Layer
- Layer 3- Network Layer
- Layer 2- Data Link Layer
- Layer 1- Physical Layer
- Hot Standby Router Protocol (HSRP). HSRP is a termination protocol developed by Cisco to provide gateway termination without any additional configuration on the end devices in the subnet.
- User Datagram Protocol -UDP port 1985 is used by HSRP active and reserve routers to send Hello messages.
- These hello messages are forwarded to multicast address 224.0.0.2 to communicate between routers in the HSRP group.
- VLSM – Variable Length Subnet Mask is used to apply a changed subnet mask to a similar class address.
The subnet mask of 192.168.100.1/28 is 255.255.255.240.
IPv6 unicast-routing
It is used to find which routing protocol is trusted. We can have any number of routing protocols. Each of them can have different paths, values stretching from 0 to 255.
Intra-site Automatic Tunnel Addressing Protocol (ISATAP). It uses virtual links to connect IPv6 sections composed within a site that is mostly using IPv4.
Syslog server is a common server used to store log information- port no: 514. It can be configured simply. It can store a large volume of data. By default, logging communications are sent to the router’s console port. It can also be sent to Syslog.
- NTP- Network Time Protocol
It is an open standard that allows you to synchronize your routers time with a consolidated time server. - It is instigated generally while using Syslog on the networks. Its port no is 123. it uses the UDP (User Datagram Protocol).
- SNMP is used for network traffic management.
- SNMP contains three elements
- Network management application “SNMP manager”
- SNMP agents running inside a managed device
- MIB-management Information Base, database object that describes the information in a programmed format, that the agent can use to occupy the data.
- OSPF works on Dijkstra Algorithm.
- First a shortest path tree is assembled.
- Secondly Routing table is populated with the resultant best paths.
- Authentication
- Encryption
- Message integrity
- It uses HMAC-SHA for security.
- EIGRP- Enhanced Interior Gateway Routing Protocol
It is a composed hybrid protocol, a Cisco patented protocol.
The symbol of EIGRP is D. - DUAL -Diffusing Update Algorithm.
- If primary route fails, EIGRP can use backup or possible routes.
- OSPF -Open Shortest Path First.
- It is an open standard routing protocol that has been executed by a wide range of network vendors, including Cisco.
- It supports multi vendors like Cisco, Alcatel, Juniper, 3Com routers. Administrative distance of OSPF is 110.
- Highest priority
- Highest router ID
- Highest IP address
- BPDU Guard is used to protect the integrity of switch ports that have port fast allowed. By default, BPDU guard is deactivated.
- it is mostly used to shut the port in an error condition.
- Disabled
- Blocking
- Listening
- Learning
- PAP- Password Authentication Protocol
- CHAP- Challenge Handshake Authentication Protocol
- PAP sends username and password checks and authorizes users.
- CHAP- challenge message passes and replies with username and password so no other router can come inside.
- Router- Each port has one isolated collision domain and one isolated broadcast domain.
- Switch- Each port has one isolated collision domain but all ports have one single broadcast domain.
- Hub- All ports have one collision area and one broadcast area.
Show run/show running-config
Show start/show start-config.
It displays iOS version, RAM space accessibility, process speed.
- 0.0.1- 255.0.0.0
- 1.1.1- 255.255.0.0
- 2.2.2- 255.255.255.0
There are two types
- Straight through cable
- Crossover cable
Help to manage, configure, install the network.
CISCO Catalyst 5000
It is a command to give router ios is stock.
STP
It is for 100 BASEFX. For use of fiber optic cables in the main transmission medium.
A protocol named BOOTP
Power over Ethernet. For-giving the information association and electric capacity to the gadget.
Network congestion occurs.
IGRP
By privileged mode.
Standard Access list.
BY using VLANs
UDP
By the Cisco AutoInstall procedure.
The high-level link control protocol
Under the protocols of the OSI layers.
In NVRAM to delete the stored configuration data.
- 32 bit – The size of IP address for IPv4
- 128 bit – The size of IP address for IPv6
The way to access the router.
By route positing
It is a firewall feature and a stateful filter.
- 179 is port number of BGP
- 0 is a port number of TCP
- O.0.0255 is the netmask of /24
- 255.255.0.0 is the netmask of /16
By STP
By HTTP protocol.
It is an AD of extended EIGPR.
It is the scope of class C address to support 254 hosts.
In the VTP domain.
MTU means maximum transmission unit i.e maximum packet size can be sent out to the data line without the need to fragment it.
The issue is more Packets will drop between sender and receiver.
Subnetting means creating smaller network from a bigger network
- IPv4 -32 bit
- IPv6 – 128 bit
- Telnet
- Auxiliary port
- Console port
255.255.255.192
TIFF, and JPEG for graphics, MIDI, MPEG and QuickTime for Video/Audio.
erase startup-config
Physical Layer data is converted in to Bits
Whenever router IOS stuck we can give this command
VLAN ID : 1
vQ211). What is Layer3 switch ?
It has both the functions (switch and router ) but this switch does not have any WAN port.
BUS,Stat,MESH,Ring,Hybrid,Tree
ARP – MAP IP to physical machine
RARP – MAC to IP Address
Maximum hop count is 15
16-bit host part and 16-bit Network part
HSRP, VRRP, and GLBP.
Link state
It works between Layer 2 and Layer 3
100base-fx its fast ethernet over the Optical fiber network.
- Console
- AUX
- VTY
- Enable secret
- Enable password
Trunk port used to connect two different switches with multiple VLAN configuration and allows send and receive data
Ethernet port used to connect two different divices like a computer to switch.
This protocol is owned by CISCO that allows exchanging VLAN information between other switches within same VTP domain. You can sync VLAN information like VLAN ID or VLAN name.
consider an example network with 50 switches, without VTP you should enter VLAN information in each and every switch manually. VTP allows you to create the VLAN only on a single switch and sync with another switch.
Transport Layers
We can use NAT to configure with few public IPs.
Loopback means looping our own machine or checking our own machine. Whether it’s working properly or not. We can use 127.0.0.1 or ping localhost.
A valid host in subnet found in between the subnets.
We hope these CCNA interview questions and answers are useful and will help you to get the best job in the networking industry. This CCNA interview questions and answers are prepared by Cisco Certified Professionals based on MNC Companies expectation. Stay tuned with us we will update New CCNA Interview questions with Answers Frequently.