Cisco 350-401 Online Practice Questions and Exam Preparation

Cisco 350-401 Online Questions & Answers

• Question 1011:

  What are two common sources of interference for Wi-Fi networks? (Choose two.)

  A. LED lights
  B. radar
  C. fire alarm
  D. conventional oven
  E. rogue AP
  B. radar
  E. rogue AP

• Question 1012:

  An engineer is implementing MPLS OAM to monitor traffic within the MPLS domain. Which action must the engineer perform to prevent from being forwarded beyond the service provider domain when the LSP is down?

  A. Disable IP redirects only on outbound interfaces.
  B. Implement the destination address for the LSP echo request packet in the 127.x.y.z/8 network.
  C. Disable IP redirects on all ingress interfaces.
  D. Configure a private IP address as the destination address of the headend router of Cisco MPLS TE.
  C. Disable IP redirects on all ingress interfaces.

• Question 1013:

  

  Refer to the exhibit. The existing configuration must be updated to terminate all EXEC sessions after 120 minutes. Which command set should be applied?

  A. line vty 0 15session-limit 120
  B. line vty 0 15exec-timeout 120
  C. line vty 0 15absolute-timeout 120
  D. line vty 0 15session-timeout 120
  B. line vty 0 15exec-timeout 120

• Question 1014:

  Which three methods does Cisco DNA Centre use to discover devices? (Choose three)

  A. CDP
  B. SNMP
  C. LLDP
  D. ping
  E. NETCONF
  F. a specified range of IP addresses
  A. CDP
  C. LLDP
  F. a specified range of IP addresses

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  Explanation

  

• Question 1015:

  An engineer must configure a ACL that permits packets which include an ACK In the TCP header.

  Which entry must be Included In the ACL?

  A. access-list 110 permit tcp any any eq 21 tcp-ack
  B. access-list 10 permit ip any any eq 21 tcp-ack
  C. access-list 10 permit tcp any any eq 21 established
  D. access-list 110 permit tcp any any eq 21 established
  D. access-list 110 permit tcp any any eq 21 established

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  Explanation

  The established keyword is only applicable to TCP access list entries to match TCP segments that have the ACK and/or RST control bit set (regardless of the source and destination ports), which assumes that a TCP connection has already been established in one direction only. Let's see an example below:

  

  Suppose you only want to allow the hosts inside your company to telnet to an outside server but not vice versa, you can simply use an "established" access-list like this:

  access-list 100 permit tcp any any established access-list 101 permit tcp any any eq telnet !

  interface S0/0 ip access-group 100 in ip access-group 101 out

  Note: Suppose host A wants to start communicating with host B using TCP. Before they can send real data, a three-way handshake must be established first. Let`s see how this process takes place:

  

  1. First host A will send a SYN message (a TCP segment with SYN flag set to 1, SYN is short for SYNchronize) to indicate it wants to setup a connection with host B. This message includes a sequence (SEQ) number for tracking purpose.

  This sequence number can be any 32-bit number (range from 0 to 232) so we use "x" to represent it.

  2. After receiving SYN message from host A, host B replies with SYN-ACK message (some books may call it SYN/ACK or SYN, ACK message. ACK is short for ACKnowledge). This message includes a SYN sequence number and an ACK number:

  + SYN sequence number (let`s called it "y") is a random number and does not have any relationship with Host A`s SYN SEQ number. + ACK number is the next number of Host A`s SYN sequence number it received, so we represent it with "x +1. It means I received your part. Now send me the next part (x + 1)".

  The SYN-ACK message indicates host B accepts to talk to host A (via ACK part). And ask if host A still wants to talk to it as well (via SYN part).

  3. After Host A received the SYN-ACK message from host B, it sends an ACK message with ACK number "y+1" to host B. This confirms host A still wants to talk to host B.

• Question 1016:

  What are two reasons why broadcast radiation is caused in the virtual machine environment? (Choose two.)

  A. vSwitch must interrupt the server CPU to process the broadcast packet.
  B. The Layer 2 domain can be large in virtual machine environments.
  C. Virtual machines communicate primarily through broadcast mode.
  D. Communication between vSwitch and network switch is broadcast based.
  E. Communication between vSwitch and network switch is multicast based.
  A. vSwitch must interrupt the server CPU to process the broadcast packet.
  B. The Layer 2 domain can be large in virtual machine environments.

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  Explanation

  Broadcast radiation is the accumulation of broadcast and multicast traffic on a computer network. Extreme amounts of broadcast traffic constitute a broadcast storm. The amount of broadcast traffic you should see within a broadcast domain is directly proportional to the size of the broadcast domain. Therefore if the layer 2 domain in virtual machine environment is too large, broadcast radiation may occur - > VLANs should be used to reduce broadcast radiation.

  Also if virtual machines communicate via broadcast too much, broadcast radiation may occur.

  Another reason for broadcast radiation is using a trunk (to extend VLANs) from the network switch to the physical server.

  Note about the structure of virtualization in a hypervisor:

  Hypervisors provide virtual switch (vSwitch) that Virtual Machines (VMs) use to communicate with other VMs on the same host. The vSwitch may also be connected to the host's physical NIC to allow VMs to get layer 2 access to the outside world.

  Each VM is provided with a virtual NIC (vNIC) that is connected to the virtual switch. Multiple vNICs can connect to a single vSwitch, allowing VMs on a physical host to communicate with one another at layer 2 without having to go out to a physical switch.

  

  Although vSwitch does not run Spanning-tree protocol but vSwitch implements other loop prevention mechanisms. For example, a frame that enters from one VMNIC is not going to go out of the physical host from a different VMNIC card.

  https://www.cisco.com/c/en/us/solutions/collateral/data-center-virtualization/net_implementation_white_paper0900aecd806a9c05.html

• Question 1017:

  Refer to the exhibit.

  

  Based on the configuration in this WLAN security setting, which method can a client use to authenticate to the network?

  A. text string
  B. username and password
  C. certificate
  D. RADIUS token
  A. text string

• Question 1018:

  A network administrator has designed a network with two multilayer switches on the distribution layer, which act as default gateways for the end hosts. Which two technologies allow every end host in a VLAN to use both gateways? (Choose two)

  A. GLBP
  B. HSRP
  C. MHSRP
  D. VSS
  E. VRRP
  A. GLBP
  D. VSS

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  Explanation

  VSS combine two switches into one logical switch.

  both of them have their own control and data plane, both of their data plane will keep alive, once the master control plane is down, the other take charge.

  MHSRP mhsrp can't let all host use both gateway, 50% host use gateway1, another 50% host use gateway 2 (fromWINDSON)

• Question 1019:

  Which method displays text directly into the active console with a synchronous EEM applet policy?

  A. event manager applet boomevent syslog pattern 'UP'action 1.0 gets 'logging directly to console'
  B. event manager applet boomevent syslog pattern 'UP'action 1.0 syslog priority direct msg 'log directly to console'
  C. event manager applet boomevent syslog pattern 'UP'action 1.0 puts 'logging directly to console'
  D. event manager applet boomevent syslog pattern 'UP'action 1.0 string 'logging directly to console'
  C. event manager applet boomevent syslog pattern 'UP'action 1.0 puts 'logging directly to console'

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  Explanation

  "Writing Input to the Active Console When a synchronous policy is triggered, the related console is stored in the publish information specification. The policy director will query this information in an event_reqinfo call, and store the given console information for use by the action puts command.

  The action puts command will write the string to the active console. A new line will be displayed unless the nonewline keyword is specified. The output from the action puts command for a synchronous applet is displayed directly to the console, bypassing the system logger. The output of the action puts command for an asynchronous applet is directed to the system logger."

  https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/eem/configuration/xe-3s/eem-xe-3s-book/eem-policy-cli.html

• Question 1020:

  Refer to the exhibit.

  

  Extended access-list 100 is configured on interface GigabitEthernet 0/0 in an inbound direction, but it does not have the expected behavior of allowing only packets to or from 192 168 0.0/16

  Which command set properly configures the access list?

  A. R1(config)#no access-list 100 deny ip any any
  B. R1(config)#no access-list 100 seq 10R1(config)#access-list 100 seq 40 deny ip any any
  C. R1(config)#ip access-list extended 100R1(config-ext-nacl)#5 permit ip any any
  D. R1(config)#ip access-list extended 100R1(config-ext-nacl)#no 10
  D. R1(config)#ip access-list extended 100R1(config-ext-nacl)#no 10

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  Explanation

  The first ACL statement of "10 deny ip any any" will match and drop all traffic so we have to remove this statement.