Test your basic knowledge |

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 common spanning tree (CST)?
Single instance of STP for all VLANs. BDPUs are sent over trunks using the native VLAN with untagged frames. Dot1q based
Hosts associated with a secondary VLAN can communicate with ports on the primary but not with another secondary VLAN
Discarding - learning - forwarding
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

2. What is the bridge priority range?
Disabled - blocking - listening - learning - forwarding
The redundant SUP is booted and sup and route engine is init'd. No L2 or L3 functions are started. Allows switchports to retain state
Used to switch packets that can't be forwarded normallly due to an encapsulation failure - unresolved address - unsupported protocol - etc.
0-65535 (def 32768) lower=better

3. What is GLBP weight?
Create 2 hsrp groups - each with the active router being different switches - then have clients point to each
If a unidirectional link is detected - the port continues normally - but the port is marked as undetermined and a syslog is generated
Gets assistance from other NSF-aware neighbors. NSF features need to be built into the routing protocols on router needing and providing assistance
By default weight is 100. Can be made dynamic per interface

4. what should you do if you expect a PAgP capable switch at the other end vs. a server or host?
Checks the destination MAC in the header against the target MAC in the ARP reply
Multicasts to 224.0.0.18 (VRRP)
Configure non-silent submode
Each frame transmits its expected duration time

5. What is a vlan?
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.
A single broadcast domain
5 (0-4 with 4 being the highest)
Causes switch to actively determine whether alternative paths exist to root bridge in case ther eis an indirect failure

6. What are the characteristics of the access layer?
An ac adaptor that plugs into a wall outlet.
Port stays up - packets from violating MACs dropped - no logging
Low cost - high density ports - multiple scalable uplinks - vlans - traffic and protocol filtering and QoS
Prevents the dhcp binding DB from being checked.

7. RSTP learning state
Incoming frames dropped - but MACs learned
Gets assistance from other NSF-aware neighbors. NSF features need to be built into the routing protocols on router needing and providing assistance
Arp for local subnet - if on different subnet - will arp for dgw
A VLAN that spans the entire fabric

8. What are the two private vlan association modes?
Makes use of the DHCP snooping database and static ip source binding entries. If enabled - switch will test addresses
Promiscuous and host
Turn on port security
Sends a voltage across the receive pairs to detect a 25k ohm resistance

9. What is DSCP codepoint AF41(34)?
The wireless clients communicate directly with no other means of connectivity such as a WAP
Flash override (class 4)
Tracks of BDPUs on nondesignated ports. When those BDPUs stop coming - the port is put into loop-inconsistent state and blocks
Effectively stops STP on filtered ports

10. Where should STP timers be configured and why?
A group of wireless devices that share a common SSID
The configureable UDLD interval must be less than max age plus two intervals of forward delay
Round robin - weighted - or host-dependent
On root - because the root bridge propagates timers with config BDPU

11. At what layer does EAPOL run?
Sets the switchport mode to access - enables portfast - and turns off channel grouping for the port
Connects to a router - firewall - or gateway. Can communicate with anything else connected to the primary or any secondary. Ignores pvlan config
Single instance of STP for all VLANs. BDPUs are sent over trunks using the native VLAN with untagged frames. Dot1q based
L2

12. What is a microcell?
When the size of a cell is intentionally reduced
CEF is distributed completely among multiple L3 forwarding engines.
Only the standby monitors the hello messages from the active router
Switch(config-if)# glbp xx where xx = group number

13. How is DHCP snooping enabled (scope)?
A TCN BDPU is sent out of the switch's root port. The switch will continue sending TCN's every hello interval until ack'd by upstream neighbor. The root bridge will send a Config BDPU to all switches
The topology is pre-populated by downloading the topology DB into the FIB and dynamically updated. Called Cisco Express Forwarding
The number of times the entry has been updated since the table was generated
Globally

14. What is RPVST+?
They shorten their bridge table aging times from default (300sec) to the fowarding delay (15 sec)
Frames that barely exceed 1518B or 1622B due to headers
The L3 forwarding engine can't forward the packet in hardware because there is no L2 next-hop address - so the packet is sent to the L3 engine to generate the ARP response
An instance of RSTP running for each VLAN on the switch. Changing from PVST to RPVST+ is disruptive

15. How does backbonefast determine whether alternative paths exist?
1- inferior BDPU on blocked-considered alternative - 2-inferior on root-all blocked ports considered alternate - 3-if inferior arrives on root and no blocked ports - assumes loss of connectivity to root
The link status stays up - but something between them has failed or is filtering traffic
1500B
Half-duplex

16. If a wireless station needs to transmit and no other device is transmitting - what happens?
Distribution layer
The station can transmit immediately and wait for an ack
Cisco ILP and 802.3af
The frame tag contains a 3 but portion tagged from 0 (low) to 7 (high)

17. RSTP forwarding state
The number of STP instances needed ot support the desired topologies and whether to map a set of VLANs to each instance
They should be an unconditional Etherchannel because the WLC can't negotiate a channel.
Frames are forwarded
LWAPP (Cisco proprietary) and CAP-WAP (standards based)

18. What is the acceptible range of VLANS?
Both layer 2 switching and IVR
1-1005 (1 and 1002-1005 are reserved)
2
The standby becomes active and stays active by default. Preemption can be configured

19. How are VACLs configured?
The port is forced to always authorize any connected client with no authentication necessary (default)
As a VLAN access map
Differentiated services
0000.0c07.acxx where xx is the group number as a 2-digit hex value

20. What is the portr ID?
Real-time functions such as beacons and probes - encryption and interactions with the client at L2
Bridge priority and MAC
16 bits (8b port priority - 8b port number)
Gets assistance from other NSF-aware neighbors. NSF features need to be built into the routing protocols on router needing and providing assistance

21. What if RSTP BDPUs aren't received?
If three are missed in a row - the neighbor is considered down and the data for that neighbor is aged
Cisco proprietary. 1 instance of STP/VLAN. Requires ISL instead of dot1q
Connects with SONET or SDH
Configure and enable DHCP snooping

22. Whan is a 10GE WAN PHY?
Configure non-silent submode
Roughly 2000
Connects with SONET or SDH
The MST instance (MSTI) runs alongside the IST and represents an STP instance

23. What are the caveats for HSRP port tracking?
Packets are discarded due to an ACL or policy action
Another router must have a higher HSRP priority and have preemt set up
Global config (vlan - vtp mode - and vtp domain) and VLAN DB mode commands. Global config is preferred because VLAN DB mode commands are legacy
Silent

24. What is a drop adjacency?

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

25. Can MSTP interoperate with 802.1q and/or PVST+?
Yes to both
Stateful switchover - redundant sup is fully booted and init'd. Both start and run config are synched as is L2 information - and switchinterfaces.
224.0.0.2 (all routers)
The ASIC

26. Can two switches in the auto(PAgP) or passive (LACP) mode create a channel? Why?
No because they only participate if asked
Used when ACLs specify port ranges...used by TCAM
For hosts that doesn't understand routing - the DGW is configured to reply with its own mac
Weak key rotation

27. What does MSTP consist of?
Port is forced to never authorize any connected client
All ports where root isn't expected
Between interfaces that are assigned to L2 VLANs or L2 trunks
Regions and instances

28. 802.11b
By an ARP access list that defines the permitted bindings
Full duplex
The redundant SUP is booted and sup and route engine is init'd. No L2 or L3 functions are started. Allows switchports to retain state
1 -2 -5.5 and 11 Mbps - Channels 1/6/11 - 2.4Ghz

29. What types of links can be trunked?
All non-edge ports are discarding. After the root bridge is identified - the port with superior BDPU becomes root
A VLAN that spans the entire fabric
FE - GE - and aggregated FE/GE Etherchannels
Untrusted

30. What happens when an ARP reply is received on an untrusted port?

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

31. How can you load-balance with HSRP?
Only for trusted Cisco gear - especially phones
0007.b4xx.xxyy where xx.xx is six 0 bits followed by a 10-bit GLBP group numberr. Yyyy is the virtual forwarder number
Source IP and MAC must match those addresses learned by DHCP snooping or a static entry
Create 2 hsrp groups - each with the active router being different switches - then have clients point to each

32. How does loop guard block ports?
Low cost - high density ports - multiple scalable uplinks - vlans - traffic and protocol filtering and QoS
Only for the offending VLAN on the port
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
Nonstop forwarding is an interactive method focusing on rebuilding the RIB after SUP switchover

33. What is the format of the VRRP virtual MAC?
0000.5e00.01xx
802.1x with EAP over LAN (EAPOL)
The time that a port spends in both listening and learning states . Default 15 seconds
Round robin - weighted - or host-dependent

34. Does a WLC and a LAP need to be on the same subnet?
1 second. Backup routers can learn the interval from the master
No
They are locally significant on an interface. HSRP1 on one VLAN is different from HSRP1 on another
Aggregation - high L3 throughput - security and policy based connectivity functions through access lists and packet filters - QoS - scalable high-speed links

35. What is DSCP codepoint AF11(10)?
Receives the first packet of a traffic flow and routes it
Automatically by duplex mode in use. Full duplex are point ot point. Half duplex ports use traditional 802.1D convergence is used.
Matching SSID - compatible data rate - authentication credentials
Priority (class 1)

36. What are the 3 trunk encap modes?
Collision domain
LACP port priority
Isl - dot1q - negotiate (default)
Promiscuous and host

37. How are multiple VLANs mapped to multiple SSIDs?
Group (0-1023) priority (1-255 higher better def 100)
By using a trunk link
Switch(config-if)# vrrp xx where xx= group number
Completed dhcp bindings - mac addresses - IP addresses - etc.

38. WPA encryption
Interim solution - uses same hardware as WEP - but uses TKIP encryption
Determines when the AVG will stop using the old VMAC in ARP replies
Etherchannel ports have inconsistent config
By brining up a tunnel between them to carry 802.11 related messages and client data.

39. What is DSCP?
Differentiated services code point
0-255
Change in trunk encap
FE - GE - and aggregated FE/GE Etherchannels

40. can root guard and udld be used together?
Using digital certificates
Using a mobility exchange message
Yes
Regions and instances

41. When DHCP snooping is turned on - by default - it considers all ports ______
Root - designated - blocking - alternate - forwarding (host)
Untrusted
Real-time functions such as beacons and probes - encryption and interactions with the client at L2
Tracks of BDPUs on nondesignated ports. When those BDPUs stop coming - the port is put into loop-inconsistent state and blocks

42. What is RPR?
A single broadcast domain
Route processor redundancy - redundant sup is partially booted and initialized and must reload module in the switch and init all sup functions
Control functions
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

43. How should backbonefast be configured?
1- inferior BDPU on blocked-considered alternative - 2-inferior on root-all blocked ports considered alternate - 3-if inferior arrives on root and no blocked ports - assumes loss of connectivity to root
On all switches in network to enable RLQ request and reply
No because they only participate if asked
If the switch or the powered device doesn't suport power class discovery

44. How are frames forwarded across a specific link?
1-client sends DHCP discover as broadcast - 2-DHCP server sends DHCP offer - client sends DHCP Request - DHCP server sends DHCP ack
Missed beacons - dropped packets (max retry) - weak signal (data rate switches down) - an AP periodicallytries to find a stronger signal
Hashing algorithm
By configuring every switch port to have an expected and controlled behavior

45. What are the 6 HSRP states?
802.1w
Can send and receive BDPUs
Disabled - init - listen - speak - standby - active
Used to switch packets destined for the null interface

46. How does a Cisco IP phone connect upstream?
Between any type of interface as long as the interface can have an L3 address assigned
Via an 802.1Q trunk or a single VLAN access port
Manages addition - deletion and renaming VLANs across the network
Forces the router to wait for a period of time after the switch is reloaded before attempting to overthrow

47. What is the RSTP default hello interval?
Variation in delay
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
1 second. Backup routers can learn the interval from the master
2 seconds

48. What is the PVLAN promiscuous mode?
Hashing algorithm
They must be carried over a voice VLAN (VVID) or over a regular data VLAN (ie. The native VLAN or the PVID)
Connects to a router - firewall - or gateway. Can communicate with anything else connected to the primary or any secondary. Ignores pvlan config
Only when a nonedge port transitions to forwarding

49. What is PVST plus (PVST+)?
The link status stays up - but something between them has failed or is filtering traffic
VTP server for domain null with no password or secure mode
Allows devices to interoperate with PVST and CST. Can use both dot1q and ISL
Only for trusted Cisco gear - especially phones

50. What is a service set?
A group of wireless devices that share a common SSID
BGP - EIGRP - OSPF - and IS-IS.
After forwarding delay - port can learn new MAC addresses
The campus network's backbone