Cisco 300-115 Online Practice Questions and Exam Preparation

Cisco 300-115 Online Questions & Answers

• Question 771:

  After the recent upgrade of the switching infrastructure, the network engineer notices that the port roles that were once "blocking" are now defined as "alternate" and "backup." What is the reason for this change?

  A. The new switches are using RSTP instead of legacy IEEE 802.1D STP.
  B. IEEE 802.1D STP and PortFast have been configured by default on all newly implemented Cisco Catalyst switches.
  C. The administrator has defined the switch as the root in the STP domain.
  D. The port roles have been adjusted based on the interface bandwidth and timers of the new Cisco Catalyst switches.
  A. The new switches are using RSTP instead of legacy IEEE 802.1D STP.

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  RSTP works by adding an alternative port and a backup port compared to STP. These ports are allowed to immediately enter the forwarding state rather than passively wait for the network to converge. RSTP bridge port roles: Root port A forwarding port that is the closest to the root bridge in terms of path cost Designated port A forwarding port for every LAN segment Alternate port A best alternate path to the root bridge. This path is different than using the root port. The alternative port moves to the forwarding state if there is a failure on the designated port for the segment. Backup port A backup/redundant path to a segment where another bridge port already connects. The backup port applies only when a single switch has two links to the same segment (collision domain). To have two links to the same collision domain, the switch must be attached to a hub. Disabled port Not strictly part of STP, a network administrator can manually disable a port Reference: http://www.cisco.com/c/en/us/support/docs/lan-switching/ spanning-tree- protocol/24062-146.html

• Question 772:

  Where can you disable MAC address learning on the switch?

  A. On the VLAN interface.
  B. Per switch port.
  C. A VLAN filter template is necessary.
  D. With the global command mac-address disable.
  A. On the VLAN interface.

• Question 773:

  Which two commands enable loop guard on a Cisco switch? (Choose two.)

  A. switch(config-if)# spanning-tree guard loop
  B. switch(config-if)# spanning-tree loop guard default
  C. switch(config)# spanning-tree loop guard default
  D. switch(config-if)# spanning-tree loopguard
  E. switch(config)# spanning-tree loopguard default
  A. switch(config-if)# spanning-tree guard loop
  E. switch(config)# spanning-tree loopguard default

• Question 774:

  If a switch that is configured globally with DHCP snooping receives a packet that has DHCP Option-82 set to 192 168.1.254, how does the switch handle the packet?

  A. It replaces the source MAC address of the packet with its own MAC address and forwards the packet
  B. It forwards the packet normally
  C. It sends a proxy ARP request for the MAC address of 192 168.1 254
  D. It drops the packet
  E. It removes the Option-82 information from the packet and forwards the packet
  F. It replaces the source IP address of the packet with its own management IP address and forwards the packet
  B. It forwards the packet normally

• Question 775:

  Which two prerequisites for HSRP to become active on an interface are true ?(Choose two)

  A. Cisco Express Forwarding must be disabled globally.
  B. The VIP must be in the same subnet as the primary IP address.
  C. A Virtual-MAC address must be configured on the interface.
  D. An IP address must be configured on the interface.
  E. PIM routing must be disabled on the interface.
  B. The VIP must be in the same subnet as the primary IP address.
  D. An IP address must be configured on the interface.

• Question 776:

  A switch is added into the production network to increase port capacity. A network engineer is configuring the switch for DHCP snooping and IP Source Guard, but is unable to configure ip verify source under several of the interfaces. Which option is the cause of the problem?

  A. The local DHCP server is disabled prior to enabling IP Source Guard.
  B. The interfaces are configured as Layer 3 using the no switchport command.
  C. No VLANs exist on the switch and/or the switch is configured in VTP transparent mode.
  D. The switch is configured for sdm prefer routing as the switched database management template.
  E. The configured SVIs on the switch have been removed for the associated interfaces.
  B. The interfaces are configured as Layer 3 using the no switchport command.

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  IP source guard is a security feature that restricts IP traffic on nonrouted, Layer 2 interfaces by filtering traffic based on the DHCP snooping binding database and on manually configured IP source bindings. You can use IP source guard to prevent traffic attacks caused when a host tries to use the IP address of its neighbor. You can enable IP source guard when DHCP snooping is enabled on an untrusted interface. After IP source guard is enabled on an interface, the switch blocks all IP traffic received on the interface, except for DHCP packets allowed by DHCP snooping. A port access control list (ACL) is applied to the interface. The port ACL allows only IP traffic with a source IP address in the IP source binding table and denies all other traffic. The IP source binding table has bindings that are learned by DHCP snooping or are manually configured (static IP source bindings). An entry in this table has an IP address, its associated MAC address, and its associated VLAN number. The switch uses the IP source binding table only when IP source guard is enabled. IP source guard is supported only on Layer 2 ports, including access and trunk ports. You can configure IP source guard with source IP address filtering or with source IP and MAC address filtering. Reference: http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3550/software/release/12- 2_25_see/configuration/guide/3550SCG/ swdhcp82.html#wp1069615

• Question 777:

  Which two pieces of information are carried in a Cisco Discovery Protocol advertisement?

  A. Processor Type
  B. VTP domain name
  C. Routing protocol
  D. Memory usage
  E. Spanning-Tree mode
  F. native VLAN-ID
  B. VTP domain name
  F. native VLAN-ID

• Question 778:

  What are the two ways to configure loop guard?

  A. config)# spanning-tree loopguard default
  B. config-if)# spanning-tree guard loop
  C. NA
  D. NA
  A. config)# spanning-tree loopguard default
  B. config-if)# spanning-tree guard loop

• Question 779:

  Which two statements about StackWise are true? (Choose two.)

  A. It groups multiple switch ports as a single EtherChannel
  B. It uses a single IP address to communicate with the network.
  C. It monitors multiple switches from a central console
  D. It enables multiple switch ports to share a single master configuration
  E. It allows multiple switches to operate as a single switch.
  B. It uses a single IP address to communicate with the network.
  E. It allows multiple switches to operate as a single switch.

• Question 780:

  Which two statements about errdisable recovery are true? (Choose two.)

  A. You can use the show errdisable recovery command to view the reason a port was error-disabled.
  B. Errdisable detection is enabled by default on ports with port security enabled
  C. You can use the show errdisable detect command to view the reason a port was error-disabled.
  D. Errdisabled autorecovery is enabled by default.
  E. Errdisabled detection is disabled by default on ports with port security enabled
  A. You can use the show errdisable recovery command to view the reason a port was error-disabled.
  B. Errdisable detection is enabled by default on ports with port security enabled