Ccna 200-301

Front 1

what show command displays statistics on a switch port?

Back 1

#'show interfaces'

Key performance counters:

Duplex/Speed, Collisions, Late Collisions, Input Errors, CRC, Interface resets

Front 2

VLAN stands for?

Back 2

Virtual Local Area Network

Front 3

What do VLANs create?

Back 3

1. Multiple broadcast domains/subnets/networks

2. Extends the layer 2 fabric (extends multiple switches)

3. Segments/isolates network traffic

Front 4

What does ROAS refer to?

Back 4

Router On A Stick

1. It allows inter-VLAN routing

(config)#int fax/x.x

encapsulation dot1q 1-4094

interface responds to packets with that specific tag.

Front 5

What does DTP stand for?

Back 5

Dynamic Trunking Protocol.

1. enabled by default

2. used to auto negotiate trunk links between two switches

3. to disable:(config-if) switchport nonegotiate

Front 6

Syntax to configure trunk links?

Back 6

(config-if)

switchport trunk encapsulation dot1q

switchport mode trunk

switchport nonegotiate

spanning-tree portfast trunk

Front 7

Syntax to change the native VLAN on a switch?

Back 7

(config-if)

switchport trunk native vlan 1-4094

- native VLAN traffic does not have a 802.1q VLAN ID added to the ethernet header of the frame.

Front 8

What VLAN numbers can be used?

Back 8

Standard range: 1 - 1005

Extended range: 1006 - 4094

Front 9

What file name in the switch flash contains VLAN configuration data?

Back 9

VLAN.DAT

To delete:

#delete flash: vlan.dat

Front 10

Syntax to delete switch config?

Back 10

#erase startup-cfg / write erase

#delete flash:vlan.dat

Front 11

What does VTP refer to?

Back 11

VLAN Trunking Protocol

Front 12

What are the trunking administrative mode options with the switchport mode command?

Back 12

(config-if)#

#switchport mode access (non-trunk port)

#switchport mode trunk

#switchport mode dynamic desirable (active negotiation)

#switchport mode dynamic auto (passive negotiation)

Front 13

Is VTP a trunking protocol?

Back 13

VTP is not a trunking protocol.

1. It is used to replicate VLANs between switches.

VTP REV# = the database revision number used to determine who has the latest version of the database.

2. Administrators have to assign VLANs to specific ports numbers.

Front 14

Syntax to turn off VTP?

Back 14

(config)#VTP mode transparent

Front 15

Syntax to see VTP summary?

Back 15

#show vtp summary

Front 16

What is a SVI?

Back 16

Switch Virtual Interface

1. (config)# int vlan 1-4094

This creates a logical layer 3 interface on the device. This is used for remote management

Front 17

What command turns on the layer 3 engine on a multi-layer switch?

Back 17

(config)# ip routing

Front 18

Trouble shooting switch commands:

Back 18

#show ip interface brief

#show run

#show interfaces status

#show run int fax/x

#show vlan brief

#show interface fax/x switchport

#show spanning-tree vlan x

# show interface trunk

Front 19

What is DHCP?

Back 19

Dynamic Host Configuration Protocol

1. uses UDP port 67 (client) and 68 (server)

2. Discovery, Offer, Request, Ack (DORA)

Front 20

What is a DHCP relay?

Back 20

A setting used to forward DHCP requests to a DHCP server residing on anther network. It is configured on the router interface.

(config-if) ip helper-address x.x.x.x (ip of svr)

Front 21

What are the two categories that routing protocols belong to?

Back 21

1. Link State

-Maintains a map of the entire network

2. Distance Vector

-Sends entire routing table to neighbours

-Only knows what the neighbour tells it

-Loop prevention mechanisms required

...3. Advance Distance Vector

Front 22

What is a classful routing protocol?

Back 22

RIP

Front 23

What version of the RIP routing protocol is classless?

Back 23

RIPv2

(config) router rip

(config-router) version 2

(config-router) no auto-summary

auto summary occurs when you have networks advertised in different classes/subnets

Front 24

What does RIP use for route computation?

Back 24

Bellman-ford algorithm

RIP uses UDP and port 520

multicast address 224.0.0.9 (RIPv2)

Front 25

What metric does RIP use?

Back 25

RIP Metric: HOPS (each router it passes through to reach the network/host adds 1 to the value)

Front 26

What does OSPF stand for?

Back 26

Open Shortest Path First

1. Link State routing protocol

2. Metric = bandwidth (sum of all interface costs to the destination)

3. Uses the dijkstra algorithm

4. Uses IP port 89

5.

Front 27

What multicast addresses does OSPF use?

Back 27

1. All OSPF routers: 224.0.0.5

2. DR-BDR OSPF routers: 224.0.0.6

Front 28

What type of network does a router know by default?

Back 28

Configured active interfaces -

Front 29

Classfull IP ranges: A, B, C, D, E:

Back 29

A class: 0-127 - 255.0.0.0

B class: 128-191 - 255.255.0.0

C class: 192-223 - 255.255.255.0

D class: 224-239 (multicasting) - NIL Subnet mask

E class: 240-255 - NIL Subnet mask

Front 30

What is administrative distance (AD)?

Back 30

Administrative Distance defines the reliability of the routing protocol.

AD = [110/1]

Front 31

What are the administrative distance values?

Back 31

Connected INT - 0

Static Route - 1

EXT BGP - 20

EIGRP - 90

IGRP - 100

OSPF - 110

IS-IS - 115

RIP - 120

Front 32

Access Control Lists types?

Back 32

Standard 1-99

Extended 100-199

Standard 48bit MAC address 700-799

Extended 48bit MAC address 1100-1199

Standard access list (expanded range) 1300-1999

Protocol type code 200-299

Extended (expanded range) 2000-2699

Front 33

What is the implicit entry for any ACL?

Back 33

Implicit deny all at the end of the ACL

Front 34

What does a standard ACL match on?

Back 34

Source IP address

- apply as close to the destination IP

Front 35

What does an extended ACL match on?

Back 35

Everything. IP/protocol/port number

- apply as close to the destination device IP as possible

Front 36

What is the syntax to create a standard ACL?

Back 36

(config) access-list 1-99 permit/deny x.x.x.x

(config) ip access-list standard name

- permit/deny x.x.x.x

Front 37

What is the syntax to create an extended ACL?

Back 37

(config) access-list 100-199 permit/deny . . .

(config) ip access-list extended name

- permit/deny ip . . .

Front 38

What is the syntax to add a permit/deny statement at a specific sequence number?

Back 38

(config) (seq-number) permit/deny . . .

Front 39

What is the syntax to resequence all of the sequence ACL numbers?

Back 39

(config) ip access-list resequence (name) x x

- first x= sequence start number

- second x= sequence number increment value

Front 40

EtherChannel standards?

Back 40

PAgP (CISCO pro) Port Aggregation Protocol

LACP IEEE802.3ad (Link Aggregation Control Protocol)

- both are negotiation protocols. Etherchannel can be statically configured without either.

(config-if) # channel-group 1 mode on

Front 41

What is Port Channelling?

Back 41

Refers to combining two-to-eight Fast Ethernet or two-Gigabit Ethernet ports together between two switches into one aggregated logical link to achieve more bandwidth and resiliency

Front 42

What settings have to match on ports identified for EtherChannel?

Back 42

All links in the bundle must match the same parameters (speed, duplex, VLAN info),

Front 43

What is the command to add a specific interface to a single EtherChannel?

Back 43

(config-if)# channel-group

Front 44

Does the channel-group (number) have to match the (config)# interface port-channel (number)?

Back 44

Yes.

Front 45

What is the command to see etherchannel status/summary?

Back 45

# show etherchannel port-channel

Front 46

How is layer 3 EtherChannel used?

Back 46

You’d use layer 3 EtherChannel when connecting a switch to multiple ports on a router

Front 47

Syntax to configure L3 EtherChannel?

Back 47

(config)# int port-channel 1

(config-if)# ip address x.x.x.x

(config-if)# int range g0/0-1

(config-if-range)# channel group 1

Front 48

What is the command to see if an ACL is applied to an interface?

Back 48

#show ip interface

Front 49

What is the commend to see configured ACLs on a router?

Back 49

#show access-list

Front 50

What are the different types of Network Address Translation?

Back 50

Static NAT (one-to-one)

Dynamic NAT (one to many; pool of IPs)

Overloading (one-to-many) AKA Port Address Translation (PAT)

Front 51

What are addresses used after NAT called?

Back 51

Global Addresses

inside global (public IP at private router)

outside global (public IP at destination router)

Front 52

What are the addresses used before NAT called?

Back 52

Local Addresses

inside local (private LAN address of host)

outside local (private LAN address of destination server)

Front 53

Syntax to configure static NAT?

Back 53

(config)#

ip nat inside source static (x.x.x.x inside local IP) (x.x.x.x outside global IP)

(config-if)# ip nat inside/outside

Front 54

Syntax to configure Dynamic NAT?

Back 54

(config)#

#ip nat pool WORD (x.x.x.x start IP) (x.x.x.x end IP) netmask (x.x.x.x subnet mask for IPs)

#access-list 1 permit any/IP address

#ip nat inside source list 1 pool WORD

(config-if)# ip nat inside/outside

Front 55

Syntax to configure PAT (overloading)?

Back 55

(config)# ip access-list standard NAT

(config-std-nacl)#permit any

(config)# ip nat inside source list NAT interface fastEthernet 0/1 overload

Front 56

What is the command to verify NAT?

Back 56

#show ip nat translations

#debug ip nat

#clear ip nat translations

#show ip nat statistics

#show ip nat translations max-entries

Front 57

Which command will allow you to see real-time translations on your router?

Back 57

#debug ip nat

Front 58

Which command will show you all the translations active on your router?

Back 58

#show ip nat translations

Front 59

Which command will show you the summary of the NAT configuration on your router?

Back 59

# show ip nat statistics

Front 60

When creating a pool of global addresses, what can be used in lieu of the 'netmask command'?

Back 60

prefix-length (X1-32)

Front 61

What is the command to add a voice VLAN to a switchport?

Back 61

(config-if)#switchport voice VLAN x

Front 62

Does the switchport encapsulate the data VLAN frames when the switchport is configured for voice and data?

Back 62

No. Only the voice VLAN frames are encapsulated.

Front 63

What are the two dynamic discovery protocols?

Back 63

Cisco Discovery Protocol (cisco proprietary)

Link Layer Discovery Protocol

Front 64

Syntax to see the global parameters of cdp?

Back 64

# show cdp

Front 65

DP timer delimits how often CDP packets are transmitted out all active interfaces.

Back 65

CDP holdtime delimits the amount of time that the device will hold packets received from neighbor devices.

Front 66

Syntax to enable/disable CDP?

Back 66

(config)#cdp run

(config)#no cdp run

Front 67

How to enable/disable cdp on a specific interface?

Back 67

(config-if)#cdp enable

(config-if)#no cdp enable

Front 68

Syntax to see connected devices multicasting CDP packets?

Back 68

#show cdp neighbors

#show cdp neighbors detail

#show cdp entry * (show same info as detail)

#show cdp entry XX(Device ID e.g. R2)

Front 69

What is the IEEE protocol for LLDP?

Back 69

802.1ab

: for Station and Media Access Control Connectivity Discovery

Front 70

Syntax to enable/disable LLDP?

Back 70

(config)#lldp run

(config)#no lldp run

(config-if)#lldp transmit

(config-if)#no lldp transmit

(config-if)#lldp receive

(config-if)#no lldp receive

Front 71

LLDP defines basic discovery capabilities, but it was also enhanced to specifically address voice applications. This version is called LLDP-MED (Media Endpoint Discovery). An important factor to remember is that LLDP and LLDP-MED are not compatible

Back 71

NTP synchronizes clocks of computer systems over packet-switched, variable-latency data networks

Front 72

Correct network time within the network is important because?

Back 72

It allows the tracking of events in the network in the correct order.

Clock synchronization is critical for the correct interpretation of events within the syslog data.

Clock synchronization is critical for digital certificates.

Front 73

A syslog server saves copies of console messages and can time-stamp them so you can view them later. What is the syntax?

Back 73

(config)#

service timestamps log datetime msec

Front 74

What is the syntax to retrieve NTP data from an NTP server?

Back 74

(config)#ntp server 172.16.10.1 version (1-4)

Front 75

What is the syntax to turn a network device into a NTP server for your LAN?

Back 75

(config)# NTP master

Front 76

Syntax to verify device is receiving NTP information?

Back 76

#show ntp status

#show ntp associations

Front 77

What is the NTP time synchronisation hierarchy?

Back 77

NTP server: makes its own time available as reference time for other clients.

NTP peer: it compares its system time to other peers until all the peers finally agree about the "true" time to synchronise to.

NTP client: it queries the reference time from one or more servers.

Front 78

What is SNMP?

Back 78

Simple Network Management Protocol

(RFC 1065)

Front 79

SNMP is an Application layer protocol that provides a message format for agents on a variety of devices to communicate with network management stations (NMSs).

Back 79

Agents send messages to the NMS station, which then either reads or writes information into a database stored on the NMS called a Management Information Base (MIB).

Front 80

NMS periodically queries or polls the SNMP agent on a device to gather and analyze statistics via GET messages. End devices running SNMP agents would send an SNMP trap to the NMS if a problem occurs.

Back 80

SNMPv1: Supports plaintext authentication with community strings and uses only UDP.

Front 81

SNMPv2c: Supports plaintext authentication with community strings with no encryption. Provides GET BULK, to gather abundant information at once and minimize the number of GET requests. It offers a more detailed error message via a reporting method called INFORM, but it’s not really more secure than v1. It uses UDP even though it can be configured to use TCP.

Back 81

SNMPv3: Supports strong authentication with MD5 or SHA, providing confidentiality and data integrity of messages via DES or DES-256 encryption between agents and managers. GET BULK is a supported feature of SNMPv3, and this version also uses TCP

Front 82

A management information base (MIB) is a collection of information that’s organized hierarchically that can be accessed by protocols like SNMP

Back 82

Organizational IDs (OIDs) are laid out as a tree with different levels assigned by different organizations. Top-level MIB OIDs belong to various standards organizations

Front 83

To obtain information from the MIB on the SNMP agent, you can use several different operations:

Back 83

GET

SET used to get information to the MIB from an SNMP agent

WALK list information from successive MIB objects

TRAP send a triggered piece of information to the SNMP manager

INFORM same as trap but with an ack

Front 84

Syntax to enable SNMPv1?

Back 84

(config)#

snmp-server community (name) ro/rw

Front 85

Syntax to add an ACL to the SNMP-server community?

Back 85

(config)#

snmp-server community (name) (ACL name)

snmp-server community (name) ro/rw (ACL name)

Front 86

Syntax to enable SNMPv2c traps?

Back 86

(config)#

snmp-server host x.x.x.x version 2c (name community string)

Front 87

What are four popular ways to gather system logs from cisco devices?

Back 87

Logging buffer (on by default)

Console line (on by default)

Terminal lines (using the terminal monitor command)

Syslog server

Front 88

Syntax to transmit syslog message to a server?

Back 88

(config)# syslog host x.x.x.x

this command can be used without the 'host' and will work the same: syslog x.x.x.x

logging informational

Front 89

What is the syntax to limit the severity level of syslog messages?

Back 89

(config)#logging trap x (level) 0-7

Front 90

What is the system message format?

Back 90

Sequence number

Facility

Severity level

Mnemonic

Description

Front 91

What does SSH stand for?

Back 91

Secure Shell

Front 92

The show cdp neighbors command provides the following information: device ID, local interface, holdtime, capability, platform, and port ID (remote interface).

Back 92

NTP and SYSLOG supplement each other:

(config)#service timestamps log datetime msec (config)#ntp server 172.16.10.1 version 4

Front 93

What is the default syslog facility level?

Back 93

By default, syslog servers receive informational messages (level 6).

Front 94

What are the four primary threats to network security?

Back 94

Unstructured Threats

Structured Threats

External Threats

Internal Threats

Front 95

What are the three primary network attacks?

Back 95

Reconnaissance attacks

Access attacks

Denial Of Service (DoS) attack

Front 96

What are four classes of malware?

Back 96

Virus

Worm

Trojan Horse

Spyware

Front 97

What configuration can you implement for additional layer two security?

Back 97

Dynamic Arp Inspection

DHCP Snooping

Port Security

Front 98

The IEEE 802.1x standard permits the implementation of identity-based networking on wired and wireless hosts by using client-server access control.

Back 98

Client: is software that runs on a client, which is 802.1x compliant .

Authenticator: (network device) is a proxy between the client and the authentication server

Authentication server (RADIUS): Server that authenticates each client before making any services available

Front 99

AAA enables systematic access security both locally and remotely.

Back 99

Authentication requires users to prove that they are who they say they are.

-validates users

Front 100

Authorization provides the needed resources specifically allowed to a certain user and permits the operations that specific user is allowed to perform.

-sets user privileges

Back 100

Accounting records what the user actually did on the network as well as which resources they accessed. It also keeps track of how much time they spent using network resources.

-logs user action

Front 101

What is the four step process for AAA authenticaion?

Back 101

1. Request authentication (client desktop)

2. Query AAA server (network device)

3. AAA server response

4. Access granted/rejected

Front 102

What are the three security server protocols supported by CISCO devices?

Back 102

RADIUS (uses UPD)

Remote Authentication Dial-in User Service

TACACS+

Terminal Access Controller Access Control System

Kerberos

Front 103

It’s important to remember that RADIUS encrypts only the password in the access-request packet, from the client to the server. The remainder of the packet is unencrypted.

Back 103

The aaa new-model command immediately applies local authentication to all lines and interfaces—except line con 0

Front 104

Syntax to configure RADIUS

Back 104

(config)# aaa new-model

(config)# radius-server host x.x.x.x key 0/7 (password)

aaa group server radius MyRadiusGroup

(config-sg-radius) server x.x.x.x

aaa authentication login default group MyRadiusGroup local

*local device login will be used if the AAA server cannot be reached.

Front 105

TACACS+ is a Cisco proprietary security server that uses TCP

Back 105

TACACS+ is configured the same way. Substitute radius-server with tacacs-server

Front 106

What does PKI refer to?

Back 106

Public Key Infrastructure (PKI) is a system that links users to public keys and verifies a user’s identity by using a certificate authority (CA).

Front 107

Syntax to configure enable password to authenticate with AAA?

Back 107

(config)#enable use-tacacs Use TACACS to check enable passwords

(config)#enable last-resort Define enable action if no TACACS servers

Front 108

What are the three roles associated with IEEE 802.1x identity-based networking?

Back 108

Client (host device)

Authenticator (network device)

Authentication Server (AAA server)

Front 109

What does FHRP refer to?

Back 109

First hop redundancy protocols (FHRPs) work by giving you a way to configure more than one physical router to appear as if they were only a single logical one.

Front 110

What are the different flavours of FHRP?

Back 110

Hot Standby Router Protocol (HSRP) Cis Pro

Virtual Router Redundancy Protocol (VRRP) Op S

Gateway Load Balancing Protocol (GLBP) Cis Pro

Front 111

Does HSRP load balance?

Back 111

No, it does not load balance. HSRP is a Cisco proprietary protocol that provides a redundant gateway for hosts on a local subnet. HSRP allows you to configure two or more routers into a standby group that shares an IP and MAC address and provides a default gateway.

Front 112

Does VRRP load balance?

Back 112

VRRP (open source) also provides a redundant gateway for hosts on a local subnet, but again, not a load-balanced one.

Front 113

What are the HSRP standby group routers?

Back 113

Active router

Standby router

Virtual router

Other router

Front 114

What should HSRP MAC addresses look like for version1 and 2?

Back 114

V1: 0000.0c07.acxx (xx=HSRP group number in hex) 0-255

V2: 0000.0c9F.Fxxx (xxx=HSRP group number in hex) 0-4095

Front 115

What does the HSRP timer include?

Back 115

The HSRP timers include hello, hold, active, and standby.

Front 116

Explain the purpose of the Hello Timer?

Back 116

The hello timer is the defined interval during which each of the routers send out Hello messages. Their default interval is 3 seconds, and they identify the state that each router is in

Front 117

Explain the purpose of the Active Timer?

Back 117

The active timer monitors the state of the active router. The timer resets each time a router in the standby group receives a Hello packet from the active router.

Front 118

Explain the purpose of the Standby Timer?

Back 118

The standby timer is used to monitor the state of the standby router. The timer resets anytime a router in the standby group receives a Hello packet from the standby router and expires based on the hold time value that’s set in the respective Hello packet.

Front 119

Syntax to modify the hello timer interval?

Back 119

(config-if)#

Standby 1 timers msec 200 msec 700

Front 120

Define the role of Other router in HSRP?

Back 120

An HSRP group can include additional routers (up to 255 per group), which are members of the group but that don’t take the primary roles of either active or standby states. These routers send “speak” messages based on the hello timer interval that informs other routers of their position in an election.

Front 121

What is the state of an 'other' HSRP router?

Back 121

Listen

Front 122

Syntax to confirm HSRP config?

Back 122

#show standby

#show standby brief

Front 123

What are the HSRP states?

Back 123

Initial (INIT)

Learn

Listen

Speak

Stanby

Active

Front 124

What are the multicast addresses for HSRP?

Back 124

HSRP V1: 224.0.0.2 UDP 1985

HSRP V2: 224.0.0.102 UDP 1985

Front 125

Define a VPN?

Back 125

VPNs are used daily to give remote users and disparate networks connectivity over a public medium like the Internet instead of using more expensive, permanent means.

Front 126

What are the benefits of VPNs?

Back 126

Security (IPsec and SSL fall into this category)

Cost saving

Scalability

Compatibility with broadband technology

Front 127

What are the three different types of enterprise managed VPNs?

Back 127

Remote access VPN

Site-to-site VPN (AKA Intranet VPN)

Extranet VPN

Front 128

What are the two categories of provider-VPNs?

Back 128

MPLS VPN:

Layer 2 MPLS VPN are a type of virtual private network (VPN) that uses MPLS labels to transport data

Layer 3 MPLS VPN provides a Layer 3 service across the backbone and a different IP subnet connects each site

Front 129

What are the two typical technologies for layer 2 MPLS?

Back 129

Virtual private wire service (VPWS) is the simplest form for enabling Ethernet services over MPLS.

Virtual private LAN switching service (VPLS)  This is an end-to-end service and is virtual because multiple instances of this service share the same Ethernet broadcast domain virtually.

Front 130

What Does MPLS Stand For?

Back 130

Multiprotocol Label Switching (MPLS) is a term commonly heard when discussing telecommunications protocols.

Front 131

What are two methods for VPN creation?

Back 131

The first approach uses IPsec to build authentication and encryption services between endpoints on an IP network. The second way is via tunneling protocols

Front 132

What are the four most common tunnelling protocols in use today?

Back 132

Layer 2 Forwarding (L2F)

Point-to-Point Tunneling Protocol (PPTP)

Layer 2 Tunneling Protocol (L2TP)

Generic Routing Encapsulation (GRE)

Front 133

because by itself, IPsec can’t be used to encrypt non-IP traffic

Back 133

if you run into a situation where you have to encrypt non-IP traffic, you’ll need to create a Generic Routing Encapsulation (GRE) tunnel for it and then use IPsec to encrypt that tunnel!

Front 134

What are the two primary security protocols used by IPsec?

Back 134

Authentication Header (AH)

Encapsulating Security Payload (ESP)

Front 135

IPsec uses various types of protocols to perform encryption. What are types of encryption algorithms used today?

Back 135

Symmetric encryption: This type of encryption requires a shared secret to encrypt and decrypt.

Asymmetric encryption: Devices that use asymmetric encryption use different keys for encryption than they do for decryption. These keys are called private and public keys

Front 136

Examples of symmetric key encryption?

Back 136

Data Encryption Standard (DES)

Triple DES (3DES)

Advanced Encryption Standard (AES)

Front 137

What is an example of an asymmetric encryption?

Back 137

Rivest, Shamir, and Adleman (RSA).

Front 138

Does GRE encrypt packets by default?

Back 138

by itself, GRE offers no security—no form of payload confidentiality or encryption whatsoever.

Front 139

What does GRE stand for?

Back 139

Generic Routing Encapsulation

Front 140

IPSEC by itself doesn’t support IP broadcast or IP multicast, preventing the use of protocols that need them like routing protocols.

Back 140

Using GRE tunnels with IPsec allows you to run a routing protocol, IP multicast, as well as multiprotocol traffic across your network.

Front 141

Define QoS?

Back 141

QoS is used to manage contention for network resources for a better end-user experience

Front 142

QoS methods focus on one of five problems that can affect data as it traverses network cable, which are?

Back 142

Delay

Jitter

Dropped packets

error

out-of-order delivery

Front 143

Define the trusts areas.

Back 143

Untrusted domain network you’re not actively managing populated by PCs, printers, etc

Trusted domain network with only administrator-managed devices like switches, routers, etc

Trusted boundary Where packets are classified and marked

Front 144

What are the QoS mechanisms?

Back 144

Classification and marking tools

Policing, shaping, and re-marking tools

Congestion management or scheduling tools

Link-specific tools

Front 145

Classification and Marking types?

Back 145

Class of Service (CoS) (wired)

Type of Service (ToS)

Differentiated Services Code Point (DSCP or DiffServ)

Class Selector 

Traffic Identifier (TID) (wireless)

Front 146

What are the classification marking tools?

Back 146

Markings

Addressing

Application signatures

Front 147

How does QoS manage network traffic?

Back 147

Policers and shapers identify traffic violations in a similar way, but they differ in their responses

Front 148

What are tools for managing congestion?

Back 148

Queuing (or buffering)

Scheduling

- Strict priority scheduling

- Round-robin scheduling 

- Weighted fair scheduling 

Front 149

List other legacy queuing methods?

Back 149

First In First Out (FIFO) 

Priority Queuing

Custom Queuing

Weighted fair Queuing

Front 150

Two newer queuing mechanisms recommended for today’s rich-media networks?

Back 150

Class Based Weighted Fair Queuing (CBWFQ)

Low Latency Queuing (LLQ):

Front 151

Cisco uses something called weighted random early detection, (WRED), a queuing method that ensures high-precedence traffic has lower loss rates than other traffic during times of congestion.

Back 151

Queuing algorithms manage the front of the queue, and congestion mechanisms manage the back of the queue.

Front 152

IPv6 Addresses?

Back 152

Global Unicast: 2000::/3 - 3FFF::/3

Link-local: FE80::/10 (equiv to 169.254.x.x) APIPA

Unique local: FC00::/7 (private LAN)

Multicast FF00::/8

Front 153

When you run IPv4 and IPv6 on a router, you have what is called “dual-stack.”

Back 153

EUI-64 (extended unique identifier) format allows the device to use its MAC address and pad it to make the interface ID for the IPv6 address.

Front 154

Syntax to enable IPv6 routing on a router?

Back 154

(config)#ipv6 unicast-routing

Front 155

(config-if)#

ipv6 address 2001:db8:3c4d:1::/64 eui-64

Back 155

To configure a router so that it uses only link-local addresses, use the ipv6 enable interface configuration command:

(config-if)#ipv6 enable

Front 156

Neighbor Discovery (NDP)ICMPv6 also takes over the task of finding the address of other devices on the local link.

Back 156

Neighbor discovery enables:

Determining the MAC address of neighbors

Router solicitation (RS) FF02::2 type code 133

Router advertisements (RA) FF02::1 type code 134

Neighbor solicitation (NS) Type code 135

Neighbor advertisement (NA) Type code 136

Duplicate address detection (DAD)

Front 157

The part of the IPv6 address designated by the 24 bits farthest to the right is added to the end of the multicast address FF02:0:0:0:0:1:FF/104 prefix and is referred to as the solicited-node address.

Back 157

This IGMP function (ipv4) has been replaced by ICMPv6, and the process has been renamed multicast listener discovery.

Front 158

What does SPAN stand for?

Back 158

Switched Port Analyser

Front 159

How does SPAN assist with troubleshooting?

Back 159

SPAN is used to analyse network traffic passing through the port by sending a copy of the traffic to another port on the switch that’s been connected to a network analyser or other monitoring device. SPAN copies the traffic that the device receives and/or sends on source ports to a destination port for analysis.

Front 160

Syntax to enable SPAN?

Back 160

Step 1: Associate a SPAN session number with the source port of what you want to monitor. (config)#monitor session 1 source interface f0/1

Step 2: Associate a SPAN session number of the sniffer with the destination interface. (config)#monitor session 1 dest interface f0/2

Front 161

Syntax to verify SPAN is configured?

Back 161

#show monitor

Front 162

What are VLAN troubleshooting commands?

Back 162

Show vlan

Show vlan brief

Show mac address-table

Show interfaces interface switchport

switchport access vlan vlan

Front 163

Trunk troubleshooting commands:

#Show interfaces trunk

#Show vlan

#Show interfaces interface trunk

#Show interfaces interface switchport

#Show dtp interface interface

Back 163

(config-if)

#switchport mode switchport mode dynamic #switchport trunk native vlan vlan

Front 164

What does CUWN stand for?

Back 164

Cisco Unified Wireless Networks

Front 165

Define the stand alone WAP?

Back 165

Not just any kind of AP can operate in the stand-alone model—only the autonomous variety of APs can do this. You configure them individually, and there’s no centralized administration point.

Front 166

Define the lightweight AP?

Back 166

APs are controlled and monitored by the WLC. All clients and APs transmit information back to the WLC, including stats about coverage, interference and even client data.

Front 167

What encapsulation protocol is used to transmit data between the AP and WLC?

Back 167

All transmitted data is sent between the APs and the WLCs via a mouthful of an encapsulation protocol called Control And Provisioning of Wireless Access Point (CAPWAP)

Front 168

What methods are used to join an AP to a WLC?

Back 168

Manual Method

DNS Method

DHCP Method

Front 169

What is the syntax to join an AP manually to a WLC?

Back 169

Use the following if AP has an IP assigned from a DHCP:

>capwap ap controller ip address x.x.x.x

If no IP has been assigned, also use:

AP#capwap ap ip address 10.30.20.101 255.255.255.0

AP#capwap ap ip default-gateway 10.30.20.1

Front 170

Explain how the DSN method works:

Back 170

To use the DNS method, create a DNS entry on a DNS server for CISCO-CAPWAP-CONTROLLER that points to my WLC AP-Manager IP

Front 171

Explain how the DHCP method works:

Back 171

The DHCP method uses hex to configure the feature. To get this done, build the hex string, which starts with F1 followed by 04 (4 x 1) if I have only one WLC in the list. It would be 08 (4 x 2) if I had two WLCs.

Front 172

The hex address = convert the WLC IP. If WLC IP is 10.10.10.10 the conversion is:

10 = 0A

10 = 0A

10 = 0A

10 = 0A

hex address: F1040A0A0A0A

Back 172

If using two WLCs and the second WLC was 30.30.30.30, the conversion would be:

30 = 1E

30 = 1E

30 = 1E

30 = 1E

hex address: F10800A0A0A0A1E1E1E1E

Front 173

Which option do you use in DHCP to add the hex value for the WLC?

Back 173

option 43:

(config)#ip dhcp pool (name)

(dhcp-config)#option 43 hex f104.0A0A.0A0A

Front 174

What is the WLC virtual interface IP by default?

Back 174

192.0.2.1

Front 175

What is the syntax to configure a LAG/EtherChannel port to a WLC?

Back 175

(config-if)#channel-group X mode on

note* must use mode 'on' as WLCs do not support LACP or PAGP autoconfigure.

Front 176

What are the AP modes?

Back 176

Local (default mode, client traffic to WLC)

Monitor (NIL client traffic)

Flexconnect (Can locally switch client traffic)

Sniffer (troubleshoot)

Rouge detector (tracks rouge APs in network)

Front 177

AP Modes Cont.

Bridge (allows AP to AP connection)

Bridge + Flex (Connects flex to mesh network)

Back 177

AP Modes Cont.

SE-Connect (AP to SPEC-AN)

Sensor used for: DNA Center’s Assurance feature

Front 178

What are the WLC and AP connections for access management?

Back 178

CDP

Telnet

SSH

HTTP

HTTPS

Console

RADIUS

Front 179

Does wireless support QoS?

Back 179

Yes. It will use the Best-Effort que by default.

-Silver

Front 180

What are the QoS profiles available for wireless?

Back 180

Bronze (background queue)

Silver (best-effort)

Gold (video queue)

Platinum (VOIP - voice queue)

Front 181

What transport layer protocol and port number does TACACS+ use for communication between network devices and AAA server?

Back 181

TCP - port 49

Front 182

What transport layer protocol and port number does RADIUS use for communication between network devices and AAA server?

Back 182

UDP 1812 (for legacy servers)

>2012: in addition, TCP port 1812 can also be used; this will service modern servers.

Front 183

What are virtualisation components?

Back 183

Hypervisor

Virtualisation guest

Virtual appliance

Virtual switch

Shared storage

Virtual storage

Front 184

Define hypervisor?

Back 184

It is the server that hosts all of the virtual servers.

Front 185

Define virtualisation guest?

Back 185

A virtual server that runs on hypervisor (a host machine)

Front 186

Define a virtual appliance?

Back 186

a virtual solution provided by a vendor i.e. a virtual version of Cisco’s ASA firewall.

Front 187

Define a virtual switch?

Back 187

All virtualisation solutions/hosts have a virtual switch (vSwitch) that it utilised for internal frame switching.

Front 188

Does a hypervisor virtual switch run STP?

Back 188

No.

Front 189

Define shared storage?

Back 189

SAN or NAS through iSCSI or Fibre Channel. This will permit all hosts in your network to access common storage.

Front 190

Define virtual storage?

Back 190

Hypervisor/hosts will use its local storage to create a logical SAN across the network which all the virtual hosts can use as virtual machines.

Front 191

Name some virtual storage solutions?

Back 191

Cisco hyperflex

VMWare virtual SAN

Microsoft storage spaces

Front 192

What does JSON stand for?

Back 192

JavaScript Object Notation

JSON structures data into key/value pairs separated with a colon inside of curly braces.

Front 193

What does YAML stand for?

Back 193

YAML Ain’t Markup Language (YAML)

Front 194

What are the main components of YAML?

Back 194

Mappings

Lists

Scalars

Front 195

What does API stand for?

Back 195

Application Programming Interfaces

Front 196

What is a common way to access APIs?

Back 196

Through Representational State Transfer (REST). REST is a resource-based API.

Front 197

What components are required to qualify as a Restful API?

Back 197

Client-Server

Stateless

Cacheable

Uniform Interface

Layered System

Code on demand

Front 198

What framework is RESTful API built on?

Back 198

HTTP

Front 199

Restful architecture uses HTTP verbs to map to something called CRUD. What does CRUD stand for?

Back 199

Create

Read

Update

Delete

Front 200

What are the HTTP verbs associated with API actions?

Back 200

HTTP VERB / API Action

Post - Create

Get - Read

Put - Update/Retrieve

Patch - Update/Modify

Delete - Delete

Front 201

What are the virtualisation types?

Back 201

Type 1 metal hypervisor—when the entire server and OS is dedicated to virtualization

Type 2 also called desktop virtualization. Virtualization solution runs on top of your desktop OS

Front 202

What does JSON stand for?

Back 202

JavaScript Object Notation (JSON)

JSON structures data into key/value pairs separated with a colon inside of curly braces

Front 203

What does YAML stand for?

Back 203

Yet another markup language:

data serialisation language which is used by growing number of tools such as Ansible.

Front 204

What are the three main components that make up YAML?

Back 204

Mappings

Lists

Scalars

Front 205

Define REST api?

Back 205

Application Programming Interfaces (APIs) allow you to quickly access an application resource without you having to manually map out the application and reverse engineer your own functionality. A RESTful API uses common HTTP requests to GET, PUT, POST, and DELETE data from a server or device.

Front 206

What is the syntax to configure port SPAN / mirroring?

Back 206

(config)#

1. monitor session (number) source interface gi1

2. monitor session (number) destination int gi2

#Show monitor session (number)

Front 207

What is the purpose of spanning tree?

Back 207

To stop layer 2 loops in the broadcast domain.

Front 208

What are the different versions of spanning tree?

Back 208

IEEE 802.1D - legacy (CST)

IEEE 802.1W - rapid spanning tree (CST)

IEEE 802.1S - MSPT (has two instances)

PVST+ (1 instance per VLAN)

rapid PVST (1 instance per VLAN)

CST = Common Spanning Tree (1 instance)

Front 209

What are BPDUs?

Back 209

Bridge Protocol Data Units. They are frames that contain information about the spanning tree protocol (STP)

Front 210

By default, how often are BPDUs sent by the switch?

Back 210

Every two seconds

Front 211

What is contained within a BPDU?

Back 211

1. Bridge ID (priority + MAC) = 8 byte value

- 2 byte priority

- 6 byte system ID

Front 212

What is the default STP priority value?

Back 212

32768; hex= 8000

+ system-id-ext (x) = vlan number. This value is added to the default priority. STP on VLAN 1 with a default STP priority. This equals 32769

STP pri = (priority + system-id-ext)

Front 213

What is the destination multicast address that BPDUs are sent to?

Back 213

MAC: (1:80:c2:00:00:00)

or for PVST: (01:00:0C:CC:CC:CD)

Front 214

What are the different types of BPDUs?

Back 214

Configuration BPDU

Topology change BPDU

Acknowledgement BPDU

Front 215

What is the 802.1D port cycle?

Back 215

1. Blocking (max-age) 20 sec

2. Listening (fwd-delay) 15 sec - BPDUs sent

3. Learning (15 sec) - BPDUs sent (MAC address -table updated)

4. Forwarding

Front 216

If the switch port link is up, which 802.1D state does the port commence at?

Back 216

Listening

Front 217

How is the STP root port selected?

Back 217

1. Lowest path cost

2. Lowest neighbor bridge ID (if path equal cost)

3. Lowest port priority (128 by default)

4. Lowest port ID

Front 218

What is the syntax to utilise the newer version of STP path cost?

Back 218

(config)# spanning-tree pathcost method long

Front 219

What are the port states for rapid-spanning tree 802.1W?

Back 219

1. learning

2. forwarding

3. discarding

Front 220

Which 802.1D port states have been merged into the discarding state for 802.1W/rapid-pvst?

Back 220

1. disabled

2. blocking

3. listening

Front 221

What are the 802.1D port roles?

Back 221

1. Root port

2. Designated port

3. Blocking

Front 222

What are the 802.1W port roles?

Back 222

1. Root port

2. Alternate port (root backup)

3. Designated port (per network segment)

4. Backup port (designated backup)

Front 223

Why would STP block a port, knowing that it is to prevent loops, on a switch?

Back 223

Because the port was not assigned the root or designated port role. It will be assigned as either an alternate or backup port.

Front 224

What is the default interface port priority for STP?

Back 224

128

Front 225

What are the types of STP links?

Back 225

1. Shared

2. Point-to-point

3. Edge

Front 226

What is the syntax to configure a point-to-point link?

Back 226

(config)#spanning-tree link-type point-to-point

Front 227

A port operating at full duplex will be assigned a ______ link state as default.

Back 227

point-to-point

Front 228

A port operating at half duplex will be assigned a ______ link state as default.

Back 228

shared

Front 229

What does RSTP use to achieve fast convergence?

Back 229

proposal/agreement handshake sequence

Front 230

What is BPDU

Back 230

Bridge Protocol Data Unit.

Front 231

What is BPDU guard?

Back 231

A security mechanism which will disable a port if any BPDUs are received on that port.

Front 232

What is the syntax to globally enable BPDU guard?

Back 232

(config)# spanning-tree portfast edge bpduguard

Note: This affects all ports on the switch that have portfast enabled. This is disabled by default.

Front 233

What is the syntax to enable BPDU guard on an interface?

Back 233

(config-if)# spanning-tree bpduguard enable

Note: Only affects the this specific port. Portfast does not have to be enabled on this port. The bpduguard will disable the port if a BPDU is received on this port.