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 the LACP priority range?
Receives the first packet of a traffic flow and routes it
Globally or per-port
Used to switch packets that can't be forwarded normallly due to an encapsulation failure - unresolved address - unsupported protocol - etc.
1-65535 (def 32768) lower priority - higher probability

2. What are the 5 steps to manualy configure STP?
1-ID link path costs - 2-ID roodt bridge - 3-select root port (1/switch) - 4-select designated port (1/segment) - 5-ID blocking port
2-8 FE - GE - or 10GE are bundled.
On the left as you face the connector
Switch(config-if)# vrrp xx where xx= group number

3. Define VRRP
0007.b4xx.xxyy where xx.xx is six 0 bits followed by a 10-bit GLBP group numberr. Yyyy is the virtual forwarder number
Port with best root path cost
It can't
Virtual Router Redundancy Protocol - pretty much the same as HSRP

4. What do you need to determine to use MSTP?
Embeds the tag within the frame
The number of STP instances needed ot support the desired topologies and whether to map a set of VLANs to each instance
All nondesignated ports - but ok for all ports
If any BDUP is received on a port - it puts the port into the errdisable state

5. What is BDPU Guard?
Up to 54Mbps - not cross-compatible - 12 to 23 clean channels - 5.8 Ghz
If any BDUP is received on a port - it puts the port into the errdisable state
Show standby
Trusted or untrusted

6. Define GLBP
A router keeps a routing table and an ARP table. The FIB combines them for every next-hop entry
A single broadcast domain
Port
Gateway load balancing protocol - cisco proprietary

7. What is 802.1x force-unauthorized?
Etherchannel ports have inconsistent config
Trunk - dynamic auto - dynamic desireable (default)
Incoming frames dropped - but MACs learned
Port is forced to never authorize any connected client

8. Whan is a 10GE WAN PHY?
Tracks of BDPUs on nondesignated ports. When those BDPUs stop coming - the port is put into loop-inconsistent state and blocks
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
When each AP stands alone within the larger network.
Connects with SONET or SDH

9. What is the STP listening state?
Use sh interface on the interface and look for error counts > 10
Can send and receive BDPUs
Hashing algorithm
Port is forced to never authorize any connected client

10. How is a QoS trust bondary configured?
Every switch and router in a network must be configured with appropriate QoS features and policies
Global config (vlan - vtp mode - and vtp domain) and VLAN DB mode commands. Global config is preferred because VLAN DB mode commands are legacy
Makes use of the DHCP snooping database and static ip source binding entries. If enabled - switch will test addresses
Distribution layer

11. What criteria are used to size a switch block?
Transmits keystrokes from phone and commands from CCM
Traffic types and patterns - amount of L3 switching cap. At dist. Layer - # users at access layer - geography - size of spanning tree domains
Used to switch packets destined for the null interface
A port can only forward or relay BDPUs - but can't receive them - disabled by default - enabled per-port - blocks port when superior BDPUs are received

12. What does MSTP do?
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
Used when there are 1 or more VLANs mapped to a single STP instance
Reboots and searches for a new WLC
When a client roams between Aps in different subnets

13. What are the RSTP port states?
Arp for local subnet - if on different subnet - will arp for dgw
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
5 (0-4 with 4 being the highest)
Discarding - learning - forwarding

14. What are the characteristics of the distribution layer?
Aggregation - high L3 throughput - security and policy based connectivity functions through access lists and packet filters - QoS - scalable high-speed links
Hosts within a secondary can communicate with each other and with the primary - but not with another secondary vlan
No
2

15. RSTP forwarding state
Frames are forwarded
On (all ports channel) - auto (channels when asked) - and desirable(actively asks to form a channel)
Packets are discarded due to an ACL or policy action
Globally

16. What is unique about HSRP group numbers?
Compatible with 802.11b - up to 54Mbps in 12 data rates - 3 channels - 2.4Ghz
Using a mobility exchange message
They are locally significant on an interface. HSRP1 on one VLAN is different from HSRP1 on another
If the client maintains the same IP address as it roams between Aps. All must have same VLAN - SSID - and subnet

17. How do you configure LACP standby links?
No
Both layer 2 switching and IVR
LACP port priority
All ARP packets that arrive on untrusted ports are inspected.

18. What is latency?
Each physical interface has a different IP address. All physical interfaces point to a virtual interface called the standby address or VIP
1 per segment
The total delay from start to finish
All ARP packets that arrive on untrusted ports are inspected.

19. What is dynamic auto?
0007.b4xx.xxyy where xx.xx is six 0 bits followed by a 10-bit GLBP group numberr. Yyyy is the virtual forwarder number
Notifies upstream neighbors by sending multicasts on behalf of hosts at the interval of the max update rate parameter.
Will trunk if asked
Regions and instances

20. How does ILP do power discovery?
Roughly 50%
Sends a test tone on the transmit pair. If a device is detected - CDP is used to narrow down the power class.
900 MHz - 2.4Ghz - and 5-6GHz
On root - because the root bridge propagates timers with config BDPU

21. If one end of an Etherchannel (either type) is set to on and the channel doesn't form - what should you check?

22. How are BDPUs spread?
Enables portfast - sets the port to access and disables PAgP
Multicast to 01-80-c2-00-00-00
1-65535 (def 32768) lower priority - higher probability
Hold time is 3xhello. A skew time of 256ms-routerpriority)/256ms is added

23. What is the port priority range?
Using a single WAP to centralize access and control over a group of wireless devices.
If the client maintains the same IP address as it roams between Aps. All must have same VLAN - SSID - and subnet
0-255 (lower is better)
Determines when the AVG will stop using the old VMAC in ARP replies

24. What are the 2 types of secondary VLAN?
Configure the timer on the AVG and let it propagate
Switched Virtual Interface - an L3 address can be assigned to a logical interface that represents an entire VLAN - which becomes the DGW for that VLAN
Isolated and community
One that can be detected on a switch interface (ie. Up/down)

25. What types of ports autonegotiate?
Full duplex
Real-time functions such as beacons and probes - encryption and interactions with the client at L2
FE and GE
Isolated and community

26. How are errdisable triggers tuned?
Connects to a router - firewall - or gateway. Can communicate with anything else connected to the primary or any secondary. Ignores pvlan config
No
Globally
Switch(config-if)# standby xx where x= group number

27. How does IPT behave when the voice VLAN is in vlan-id mode?
Only for the offending VLAN on the port
Can hear only BDPUs
Data goes over native vlan - voice goes over specified VLAN - voice QOS is 802.1p
The total delay from start to finish

28. What does the switchport host macro do?
Single instance of STP for all VLANs. BDPUs are sent over trunks using the native VLAN with untagged frames. Dot1q based
When the size of a cell is intentionally reduced
Both ends should be on because on modes doesn't send PAgP or LACP packets
Enables portfast - sets the port to access and disables PAgP

29. What are the PAgP negotiation modes
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
On (all ports channel) - auto (channels when asked) - and desirable(actively asks to form a channel)
1 to 64
Per-port or globally for all fiber-optic ports. Can be enabled globally - but will only affect fiber ports

30. CAM table entries are purged when....
0007.b4xx.xxyy where xx.xx is six 0 bits followed by a 10-bit GLBP group numberr. Yyyy is the virtual forwarder number
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
A MAC is seen on a different port
Packets are discarded due to an ACL or policy action

31. What is step 1 of enabling IP source guard?
FE and GE
900 MHz - 2.4Ghz - and 5-6GHz
Configure and enable DHCP snooping
Per VLAN

32. What are TCAM entries composed of?
When the AP uplinks to an Ethernet network.
Value - mask - and result (VMR) combinations
Each peer sends and receives hellos. Def hello is 3 sec - def hold is 10 sec
Nonstop forwarding is an interactive method focusing on rebuilding the RIB after SUP switchover

33. What is best effort delivery QOS?
The active router. All other routers are in backup state
BGP - EIGRP - OSPF - and IS-IS.
Switches make an effort to move packets as quickly as possible
A private VLAN can be logically associated with a special secondary vlan

34. What is an isolated secondary VLAN?

35. If a wireless station needs to transmit and another device is transmitting - what happens?
By encapsulating each frame in a header and trailer
The station must wait until the frame in progress has completed - then wait a random amount of time before transmitting
After forwarding delay - port can learn new MAC addresses
Used to switch packets that can't be forwarded normallly due to an encapsulation failure - unresolved address - unsupported protocol - etc.

36. How does HSRP gateway addressing work
Protects STP when a physical malfunction only allows traffic in 1 direction - even though the link shows as up (cisco proprietary)
If the switch or the powered device doesn't suport power class discovery
Each physical interface has a different IP address. All physical interfaces point to a virtual interface called the standby address or VIP
Hashing algorithm

37. What is the GLBP AVG?
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
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
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
No because they only participate if asked

38. What are the 5 STP port roles?
Admin down
A port can only forward or relay BDPUs - but can't receive them - disabled by default - enabled per-port - blocks port when superior BDPUs are received
Root - designated - blocking - alternate - forwarding (host)
900 MHz - 2.4Ghz - and 5-6GHz

39. Which 4 things must be agreeable to trunk?
5 (0-4 with 4 being the highest)
1- trunking mode - 2-trunk encapsulation - 3-native VLAN - 4-allowed VLAN
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
Up to 4 can be used in a group. Called active virtual forwarders (AVF)

40. What is an indirect topology change?
TCAM
Differentiated services
The link status stays up - but something between them has failed or is filtering traffic
By creating a static IP binding

41. How does a LAP and a WLC authenticate between each other?
Lowest cumulative cost to root
Regions and instances
Used when there are 1 or more VLANs mapped to a single STP instance
Using digital certificates

42. What pins does FE use?
Trusted or untrusted
Yes
1/2 and 3/6
Differentiated services

43. What is the size of ISL encapsulation?
26-byte header - 4-byte trailer with CRC
Arp for local subnet - if on different subnet - will arp for dgw
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
802.1x with EAP over LAN (EAPOL)

44. What is the default FE duplex?
Each network device handles packets individually with no advance reservations
LACP port priority
Tracks of BDPUs on nondesignated ports. When those BDPUs stop coming - the port is put into loop-inconsistent state and blocks
Full duplex

45. What is the PVLAN host mode?
Allows devices to interoperate with PVST and CST. Can use both dot1q and ISL
Connects to a host on an isolated or community vlan. Communicates only with promiscuous port or ports on same community vlan
On by default
That they aren't using the same frequencies.

46. What does the switchport host macro do?
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
Virtual Router Redundancy Protocol - pretty much the same as HSRP
Sets the switchport mode to access - enables portfast - and turns off channel grouping for the port
Option 43

47. What does the static keyword do when applying an arp ACL?
Prevents the dhcp binding DB from being checked.
Packets must be sent to the L3 engine for further processing
Multicast to 01-80-c2-00-00-00
FE - GE - and aggregated FE/GE Etherchannels

48. What routing protocols support NSF?
Using digital certificates
Time between BDPUs sent by root bridge. Default of 2 seconds
Only when a nonedge port transitions to forwarding
BGP - EIGRP - OSPF - and IS-IS.

49. How is 802.1x configured for port security?
Root - designated - blocking - alternate - forwarding (host)
Local only
RADIUS
Using digital certificates

50. Where is root guard enabled?