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 are the 5 STP port roles?
Root - designated - blocking - alternate - forwarding (host)
Incoming frames dropped - but MACs learned
On by default
Distribution layer


2. What does MSTP consist of?
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.
The station can transmit immediately and wait for an ack
10-15%
Regions and instances


3. CAM table entries are purged when....
The port is forced to always authorize any connected client with no authentication necessary (default)
A MAC is seen on a different port
Root - designated - alternate - and backup
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


4. How do you configure DAI for statically configured IP addresses?
1 -2 -5.5 and 11 Mbps - Channels 1/6/11 - 2.4Ghz
They shorten their bridge table aging times from default (300sec) to the fowarding delay (15 sec)
Critical...used most often for IPT
By an ARP access list that defines the permitted bindings


5. What is errdisable pagp-flap?
Only the standby monitors the hello messages from the active router
Etherchannel ports have inconsistent config
MAC of the end device
All fiber-optic links between switches (must be enabled on both ends)


6. 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


7. How does PAgP form etherchannels?
Only on ports that have same static VLANs or trunking. It also modifies parameters of the channel if one of the ports is modified
A point to point port type
Embeds the tag within the frame
Must be same type - speed - VLAN(s) - native vlan - pass the same set of vlans -duplex - and spanning tree settings


8. What is an IST instance?
They must be carried over a voice VLAN (VVID) or over a regular data VLAN (ie. The native VLAN or the PVID)
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
Discarding - learning - forwarding
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.


9. What does the switchport host macro do?
Effectively stops STP on filtered ports
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
Enables portfast - sets the port to access and disables PAgP
All ports where root isn't expected


10. What is the range of HSRP group numbers?
0-255
One that can be detected on a switch interface (ie. Up/down)
Variation in delay
If the switch or the powered device doesn't suport power class discovery


11. What does the minimum keyword do in HSRP?
Port with best root path cost
Half-duplex
Those that connect to other switches
Forces the router to wait for a period of time before attempting overthrow


12. What is the STP listening state?
Regions and instances
The priority is a 2 byte value followed by the MAC that decides which ports are actively participating in Etherchannel (lower=higher priority)
The active router. All other routers are in backup state
Can send and receive BDPUs


13. How do you renable an err-disable port by default?
Manually
PAgP (Cisco proprietary) and LACP (standards-based)
With portfast
Control functions


14. What are the 2 choices for VLANs with IPT?
They must be carried over a voice VLAN (VVID) or over a regular data VLAN (ie. The native VLAN or the PVID)
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 active router. All other routers are in backup state
The number of times the entry has been updated since the table was generated


15. RSTP uses which standard?
A host port goes up or down
802.1w
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
If any BDUP is received on a port - it puts the port into the errdisable state


16. What is a VRRP group?
The same as a standby group in HSRP
5 classes with 3 drop precedences
Data and voice over native vlan - no QOS but still uses 802.1p trunk
Route processor redundancy - redundant sup is partially booted and initialized and must reload module in the switch and init all sup functions


17. How many tunnels exist between the LAP and WLC?
The ASIC
Source IP and MAC must match those addresses learned by DHCP snooping or a static entry
2 - one for control messages and one for data
Sends a test tone on the transmit pair. If a device is detected - CDP is used to narrow down the power class.


18. Where should STP timers be configured and why?
Globally
The DCF interframe space- the random backoff time before a wireless set can transmit
On root - because the root bridge propagates timers with config BDPU
They disguise the origin of an attack


19. RSTP alternate port
One that can be detected on a switch interface (ie. Up/down)
Disabled - blocking - listening - learning - forwarding
Port with alternative path to root less desirable than root
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


20. How many links can be used in an EtherChannel?
2-8 FE - GE - or 10GE are bundled.
To the virtual port-channel interface
5 classes with 3 drop precedences
Regions and instances


21. RSTP forwarding state
All non-edge ports are discarding. After the root bridge is identified - the port with superior BDPU becomes root
Frames are forwarded
Half because transmitting and receiving stations use the same frequency
1-1005 (1 and 1002-1005 are reserved)


22. What is a QoS trust boundary?
Bridge priority and MAC
Any dhcp reply coming from an untrusted port is discarded and the offending port is put in errdisable
That they aren't using the same frequencies.
The point at which a switch decides to trust incoming Qos. Usually at boundary with ISP


23. What is the cost of a 10Gbps link?
By sending a gratuitous ARP
2
The standby becomes active and stays active by default. Preemption can be configured
The ASIC


24. what do multilayer switches do?
Both layer 2 switching and IVR
Each peer sends and receives hellos. Def hello is 3 sec - def hold is 10 sec
80% of the user traffic should stay in the VLAN
Differentiated services code point


25. What is a microcell?
Effectively stops STP on filtered ports
When the size of a cell is intentionally reduced
Only for trusted Cisco gear - especially phones
RPR - RPR+ - and SSO


26. What are the gotchas for uplinkfast?

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


27. What is best effort delivery QOS?
Switches make an effort to move packets as quickly as possible
LACP port priority
Change in trunk encap
1- trunking mode - 2-trunk encapsulation - 3-native VLAN - 4-allowed VLAN


28. What is an isolated secondary VLAN?

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


29. 802.11g
Compatible with 802.11b - up to 54Mbps in 12 data rates - 3 channels - 2.4Ghz
Very high L3 throughput - no access lists or port filtering - redundancy and resilience - advanced QoS
Real-time Transport Protocol
Half because transmitting and receiving stations use the same frequency


30. What is layer 2 roaming?
Dynamic WEP keys that change periodically
The station must wait until the frame in progress has completed - then wait a random amount of time before transmitting
If the client maintains the same IP address as it roams between Aps. All must have same VLAN - SSID - and subnet
Those that connect to other switches


31. What are the RSTP port roles?
1 per segment
Root - designated - alternate - and backup
Src-dst-ip
L2


32. How does a DHCP server send WLC addresses?
Create 2 hsrp groups - each with the active router being different switches - then have clients point to each
They must be carried over a voice VLAN (VVID) or over a regular data VLAN (ie. The native VLAN or the PVID)
Option 43
Priority (class 1)


33. What are the RSTP port states?
802.11
The link status stays up - but something between them has failed or is filtering traffic
Discarding - learning - forwarding
The distribution layer should have only L3 links


34. What is RPR?
Route processor redundancy - redundant sup is partially booted and initialized and must reload module in the switch and init all sup functions
Source IP and MAC must match those addresses learned by DHCP snooping or a static entry
PAgP (Cisco proprietary) and LACP (standards-based)
When a wireless station transmits a frame - the receiving one must send an ack


35. By default - what layer do catalyst switchports operate on?
No
L2
Checks the source MAC in the header against the sender MAC in the ARP reply
Gateway load balancing protocol - cisco proprietary


36. What is the core block?

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


37. the static port to vlan membership is handled in _____
Embeds the tag within the frame
The ASIC
BGP - EIGRP - OSPF - and IS-IS.
Trusted ports


38. RSTP learning state
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
Distribution
Cisco recommends only on the root bridge
Incoming frames dropped - but MACs learned


39. If a port is configured for errdisable auto recovery - how long does it stay down?
300 sec by default
No
Any dhcp reply coming from an untrusted port is discarded and the offending port is put in errdisable
Group (0-255) - priority (1-254 254 is highest - 100 default)


40. EAP encryption
Dynamic WEP keys that change periodically
Incoming frames are dropped (combination of disabled - blocking - and listening)
224.0.0.2 (all routers)
Yes


41. What is a baby giant frame?
Per-port or globally for all fiber-optic ports. Can be enabled globally - but will only affect fiber ports
1-enable AAA on switch - 2-define RADIUS servers - 3-define authentication method - 4-enable 802.1x on switch - 5-conf. 802.1x ports - 6-allow hosts
Critical...used most often for IPT
Frames that barely exceed 1518B or 1622B due to headers


42. What are the 2 UDLD modes?
When the AP uplinks to an Ethernet network.
By using a trunk link
Normal and aggressive
A VLAN that spans the entire fabric


43. How does DAI work?
By sending a gratuitous ARP
Hashing algorithm
All ARP packets that arrive on untrusted ports are inspected.
When each AP stands alone within the larger network.


44. What is a CEF punt?

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


45. What is the VRRP master router?
After forwarding delay - port can learn new MAC addresses
The active router. All other routers are in backup state
Transmits keystrokes from phone and commands from CCM
Multicasts to 224.0.0.18 (VRRP)


46. What is the adjacency table?
The topology is pre-populated by downloading the topology DB into the FIB and dynamically updated. Called Cisco Express Forwarding
A router keeps a routing table and an ARP table. The FIB combines them for every next-hop entry
A point to point port type but the neighboring device runs traditional 802.1D STP
When a port moves into forwarding or from fowarding or learning to blocking.


47. What does port-security restrict do?
They should be an unconditional Etherchannel because the WLC can't negotiate a channel.
The frame tag includes a 3 bit COS value from 0 (low) to 7 (high). Native vlans are untagged so no COS
Matching SSID - compatible data rate - authentication credentials
Port stays up - but packets from violating MACs are dropped. Switch logs violating packets


48. Does VTP pass private VLAN configuration?
1 second. Backup routers can learn the interval from the master
Between any type of interface as long as the interface can have an L3 address assigned
No
A key string of up to 8 characters is sent. Default is cisco.


49. What is GLBP weight?
By default weight is 100. Can be made dynamic per interface
63 kbps
From the DHCP snooping database or from static entries
Via an 802.1Q trunk or a single VLAN access port


50. How does RSTP converge?
Backbonefast uses RLQ to determine if upstream switches have stable connections to root bridge
If a proposal is received - the recipient isolates - all nonedge ports blocked until proposal sent causing neighbors to synch - which propagates out in waves
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
Hosts associated with a secondary VLAN can communicate with ports on the primary but not with another secondary VLAN