CCNP Switch Deck

Instructions:

• Answer 50 questions in 15 minutes.
• If you are not ready to take this test, you can study here.
• Match each statement with the correct term.
• Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What is a null adjacency?
Access
Used to switch packets destined for the null interface
Turn on port security
If three are missed in a row - the neighbor is considered down and the data for that neighbor is aged


2. If a wireless station needs to transmit and no other device is transmitting - what happens?
The time that a port spends in both listening and learning states . Default 15 seconds
Should be used on access switches - can't be used on root - keeps enabled switch from becoming root by raising priority of switch and all ports - making them undesirable
The station can transmit immediately and wait for an ack
Controls where candidate root bridges can be connected and found on a network


3. WPA encryption
Every switch and router in a network must be configured with appropriate QoS features and policies
MAC addresses are learned from the source MAC of incoming frames. If the destination address is unknown - the frame is flooded out all except the receiving port.
Virtual Router Redundancy Protocol - pretty much the same as HSRP
Interim solution - uses same hardware as WEP - but uses TKIP encryption


4. What is a baby giant frame?
FIB
The port asks the other end to trunk
The MST instance (MSTI) runs alongside the IST and represents an STP instance
Frames that barely exceed 1518B or 1622B due to headers


5. Which fiber is the receive?
All L2 connectivity should be contained within the access layer.
During the time that the FIB entry is in CEF glean waiting for ARP entries - subsequent packet to that host are dropped to keep input queues from filling
If a unidirectional link is detected - the switch doesn't try to reestablish the link. ULD msgs are sent once/sec for 8 seconds - then the port is err-disabled
On the left as you face the connector


6. What types of link can an etherchannel be?
Plain text or md5
Access or trunk
Automatically by duplex mode in use. Full duplex are point ot point. Half duplex ports use traditional 802.1D convergence is used.
No because they only participate if asked


7. How does adding option-82 to DHCP snooping affect things?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


8. What is latency?
When the AP uplinks to an Ethernet network.
The total delay from start to finish
When a wireless station transmits a frame - the receiving one must send an ack
MAC addresses are learned from the source MAC of incoming frames. If the destination address is unknown - the frame is flooded out all except the receiving port.


9. How do you configure DAI for statically configured IP addresses?
Flash (class 3)
By an ARP access list that defines the permitted bindings
Will trunk if asked
0-255


10. How are errdisable triggers tuned?
300 sec by default
To a VLAN and not to a VLAN interface (SVI)
The RP listens to a flow's 1st packet for the dest. The SE listens to the packet and dest and puts a shortcut in the MSL cache. Netflow switching - route once - switch many
Globally


11. what must be done on an SVI before it is activated?
No shut
300 sec
Both ends should be on because on modes doesn't send PAgP or LACP packets
Using digital certificates


12. If a port is configured for errdisable auto recovery - how long does it stay down?
1-(opt) configure load balancing - 2-select the interface(s) - 3-assign the protocol - 4-select the mode and submode
300 sec by default
From the DHCP snooping database or from static entries
Prevents the dhcp binding DB from being checked.


13. How does RSTP identify a topology change?
Data goes over native vlan - voice goes over specified VLAN - voice QOS is 802.1p
The time interval that a switch stores a DBPU before discarding it. Default 20 seconds
Only when a nonedge port transitions to forwarding
Each network device handles packets individually with no advance reservations


14. Can loop guard and udld be used together?
1- enable qos - 2-define qos parameters to be trusted - 3-make trust conditional - 4-instruct IP phone how to extnd boundary
Group (0-1023) priority (1-255 higher better def 100)
Yes
Real-time Transport Protocol


15. What is the STP blocking state?
Roughly 2000
Can hear only BDPUs
Two distribution switches that aggregate one or more access switches
Another router must have a higher HSRP priority and have preemt set up


16. What is RPR+?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


17. What is the STP forward delay timer?
The port will operate under 802.1D rules. If they are received on the same port - it will run 802.1D until the migration delay expires
The time that a port spends in both listening and learning states . Default 15 seconds
Within a single MST region - an IST instances runs to work out a loop free topology between links where CST meets the region boundary and all switches in the region. It runs at the boundary.
802.1w


18. What must you be sure of if AP cells overlap?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


19. What is a drop adjacency?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


20. What is the GLBP AVG?
One router is the active virtual gateway - has highest priority or IP in group - answers all ARP requests and gives MAC based on load balancing
Sets the switchport mode to access - enables portfast - and turns off channel grouping for the port
Within a single MST region - an IST instances runs to work out a loop free topology between links where CST meets the region boundary and all switches in the region. It runs at the boundary.
Create 2 hsrp groups - each with the active router being different switches - then have clients point to each


21. What is DSCP codepoint AF21(18)?
Causes switch to actively determine whether alternative paths exist to root bridge in case ther eis an indirect failure
0-255
Immediate (class 2)
1-(opt) configure load balancing - 2-select the interface(s) - 3-assign the protocol - 4-select the mode and submode


22. How is root port decided upon?
Between interfaces that are assigned to L2 VLANs or L2 trunks
Used when ACLs specify port ranges...used by TCAM
0-255 (lower is better)
Lowest cumulative cost to root


23. How does VRRP do tracking?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


24. How many 802.3af power classes are there?
With portfast
With the skinny protocol
5 (0-4 with 4 being the highest)
Source IP and MAC must match those addresses learned by DHCP snooping or a static entry


25. What are the steps to configure MST?
The point at which a switch decides to trust incoming Qos. Usually at boundary with ISP
1- enable MST - 2-enter MST config mode - 3-assign region name and region configuration rev - 4-map vlans to an MSTI - 5-show pending changes - 6- commit by exiting
Used to switch packets that can't be forwarded normallly due to an encapsulation failure - unresolved address - unsupported protocol - etc.
The priority is a 2 byte value followed by the MAC that decides which ports are actively participating in Etherchannel (lower=higher priority)


26. How does DAI work?
They should be an unconditional Etherchannel because the WLC can't negotiate a channel.
All ARP packets that arrive on untrusted ports are inspected.
2 - one for control messages and one for data
Port stays up - packets from violating MACs dropped - no logging


27. At what layer does EAPOL run?
L2
On the left as you face the connector
A host port goes up or down
Limits the number if dhcp requests on a port


28. What is RPVST+?
1- enable MST - 2-enter MST config mode - 3-assign region name and region configuration rev - 4-map vlans to an MSTI - 5-show pending changes - 6- commit by exiting
Source IP and MAC must match those addresses learned by DHCP snooping or a static entry
An instance of RSTP running for each VLAN on the switch. Changing from PVST to RPVST+ is disruptive
Root - designated - alternate - and backup


29. How do you prevent VLAN hopping?
1-lowest root bridge ID - 2-lowest root path cost - 3-lowest bridgeID - 4-lowest port ID
Yes
Aggregation - high L3 throughput - security and policy based connectivity functions through access lists and packet filters - QoS - scalable high-speed links
Set the native VLAN of a trunk to a bogus or unused VLAN ID then prune the native VLAN off both ends of the trunk


30. What duplex setting does 802.11 use and why?
CEF is distributed across multiple L3 forwarding engines - typically on Catalyst 6500 line cards each having only a subset
Half because transmitting and receiving stations use the same frequency
The DCF interframe space- the random backoff time before a wireless set can transmit
Discarding - learning - forwarding


31. What are the steps to configure a LACP port channel?
1-(opt) set system priority - 2-select interface(s) - 3-assign the protocol - 4-set the mode - 5-(opt) set the port priority
Routers at the distribution layer become the bottlenecks or broadcast or multicast traffic slows the switches in the switch block
Prevents the dhcp binding DB from being checked.
On all switches in network to enable RLQ request and reply


32. If a wireless station needs to transmit and another device is transmitting - what happens?
Tracks of BDPUs on nondesignated ports. When those BDPUs stop coming - the port is put into loop-inconsistent state and blocks
Source IP - dest IP - combination of source and dest IP - source and dest MAC - or TCP/UDP port numbers
Yes
The station must wait until the frame in progress has completed - then wait a random amount of time before transmitting


33. What is a CEF glean?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


34. RSTP edge port
Only a single host connects . If one BDPU is received - it is no longer an edge port
The TOS field in the header is used. 2 methods 3 bits or 6 bits
Listens to the first packet going to router and away from the router. If it can switch in both directions - it learns a shortcut path so subsequent packets can be switched without the RP
4


35. What is backbonefast?
2 strand MMF with MT-RJ or SC connectors
Causes switch to actively determine whether alternative paths exist to root bridge in case ther eis an indirect failure
0007.b4xx.xxyy where xx.xx is six 0 bits followed by a 10-bit GLBP group numberr. Yyyy is the virtual forwarder number
Best effort delivery - integrated services model - and differentiated services model


36. Each switch port is a _____ ______
Each network device handles packets individually with no advance reservations
Collision domain
Critical...used most often for IPT
Configure the timer on the AVG and let it propagate


37. What are the caveats for HSRP port tracking?
Another router must have a higher HSRP priority and have preemt set up
Collision domain
Listens to the first packet going to router and away from the router. If it can switch in both directions - it learns a shortcut path so subsequent packets can be switched without the RP
TCAM


38. What is a QoS trust boundary?
The point at which a switch decides to trust incoming Qos. Usually at boundary with ISP
134 bits - consisting of source and destination addresses and protocol information from the packet or frame
Nonstop forwarding is an interactive method focusing on rebuilding the RIB after SUP switchover
Either desirable or auto mode


39. What is topology-basec caching?
The topology is pre-populated by downloading the topology DB into the FIB and dynamically updated. Called Cisco Express Forwarding
1- root bridge is elected - 2-the state of eery switch port in the STP domain must be brought from blocking state to the appropriate state
Configure non-silent submode
Transmits keystrokes from phone and commands from CCM


40. What is the STP learning state?
2-8 FE - GE - or 10GE are bundled.
Can send and receive BDPUs
16 - of which up to 8 are active. The others are in standby
After forwarding delay - port can learn new MAC addresses


41. What does Root Guard do?
Configuration and TCN
1-65535 (def 32768) lower priority - higher probability
Trunk
Controls where candidate root bridges can be connected and found on a network


42. What is DSCP codepoint EF(46)?
Root - designated - blocking - alternate - forwarding (host)
Yes
Control functions
Critical...used most often for IPT


43. What does port-security protect do?
The RP listens to a flow's 1st packet for the dest. The SE listens to the packet and dest and puts a shortcut in the MSL cache. Netflow switching - route once - switch many
Embeds the tag within the frame
Port stays up - packets from violating MACs dropped - no logging
Used to switch packets that can't be forwarded normallly due to an encapsulation failure - unresolved address - unsupported protocol - etc.


44. How does the standby handle ARP issues after it becomes active?
All L2 connectivity should be contained within the access layer.
By sending a gratuitous ARP
1/2 and 3/6
0-255


45. What method of QOS does voice traffic use most frequently?
When the AP uplinks to an Ethernet network.
Trunk
Differentiated services
2 strand MMF with MT-RJ or SC connectors


46. Which ports should you consider trusted for DAI?
0-255
Those that connect to other switches
Any ports associated with an isolated vlan can reach the primary - but not any other secondary. Hosts withn an isolated vlan can't reach each other
Switch(config-if)# vrrp xx where xx= group number


47. unknown unicast flooding
The number of STP instances needed ot support the desired topologies and whether to map a set of VLANs to each instance
MAC addresses are learned from the source MAC of incoming frames. If the destination address is unknown - the frame is flooded out all except the receiving port.
1 to 64
By short-circuiting the max age timer


48. How should the switch port to which a LAP be configured?
Data goes over native vlan - voice goes over specified VLAN - voice QOS is 802.1p
Backbonefast uses RLQ to determine if upstream switches have stable connections to root bridge
Access
Real-time functions such as beacons and probes - encryption and interactions with the client at L2


49. What is Per VLAN STP (PVST)?
Only the standby monitors the hello messages from the active router
Cisco proprietary. 1 instance of STP/VLAN. Requires ISL instead of dot1q
Every switch and router in a network must be configured with appropriate QoS features and policies
Local only


50. What is the VRRP skew time?
Per VLAN
Group (0-1023) priority (1-255 higher better def 100)
1 second. Backup routers can learn the interval from the master
Hold time is 3xhello. A skew time of 256ms-routerpriority)/256ms is added