Juniper JN0-400 Exam - CertifySky.com

Free JN0-400 Sample Questions:

Q: 1 Within a virtual chassis, which type of switch maintains the forwarding table?
A. line card
B. master switch
C. routing switch
D. forwarding switch
Answer: B

Q: 2 Which built-in security mechanism in the Link Layer Discovery Protocol (LLDP) can be used to encrypt advertisements?
A. There is no encryption in LLDP.
B. A plain-text password can be used.
C. MD5 hashing of the password can be used.
D. SHA-1 hashing of the password can be used.
Answer: A

Q: 3 What are three key features of virtual chassis? (Choose three.)
A. dedicated active and standby switch fabrics
B. dedicated master and backup routing engines
C. ability to configure vcp-0 and vcp-1 interfaces to run at various speeds
D. ability to upgrade all members of a virtual chassis from the master switch
E. ability to interconnect members of a virtual chassis using the 10-Gigabit Ethernet uplink ports
Answer: B, D, E

Q: 4 Which two actions are available when configuring the MAC limiting feature? (Choose two.)
A. Drop the traffic.
B. Change the forwarding-class of the traffic.
C. Redirect the traffic with changed loss-priority.
D. Shut down the interface so traffic will be blocked.
Answer: A, D

Q: 5 You are configuring the voice VLAN feature on an EX-series switch on interface ge-0/0/5.
Which configuration would you use?
A. ethernet-switching-options {
voice-vlan {
interface ge-0/0/5.0 {
vlan voice-over-ip;
forwarding-class expedited-forwarding;
}
B. ethernet-switching-options {
voip {
interface ge-0/0/5.0 {
member-vlan voice-over-ip;
forwarding-class expedited-forwarding;
}
C. ethernet-switching-options {
voip {
interface ge-0/0/5.0 {
vlan voice-over-ip;
forwarding-class expedited-forwarding;
}
D. ethernet-switching-options {
voice-vlan {
interface ge-0/0/5.0 {
member-vlan voice-over-ip;
forwarding-class expedited-forwarding;
}
Answer: C

Q: 6 You want to configure a static default route to the gateway 10.1.1.1. Which set command will accomplish this task?
A. set routes static route 0.0.0.0/0 gateway 10.1.1.1
B. set protocols static route 0.0.0.0/0 next-hop 10.1.1.1
C. set family inet static route 0.0.0.0/0 next-hop 10.1.1.1
D. set routing-options static route 0.0.0.0/0 next-hop 10.1.1.1
Answer: D

Q: 7 Which three are included in the factory-default configuration? (Choose three.)
A. RSTP
B. LLDP
C. SNMP
D. user authentication
E. family ethernet-switching for all ports
Answer: A, B, E

Q: 8 Which directory contains the rollback 4 configuration?
A. /config
B. /var/config
C. /var/db/rollback
D. /config/db/config
Answer: D

Q: 9 Which statement describes a benefit of Link Layer Discovery Protocol-Media Endpoint Discovery (LLDP-MED)?
A. Allows an LLDP-MED-enabled switch to deliver VLAN and Class of Service (CoS) settings to a
neighboring IP phone.
B. Allows an LLDP-MED-enabled switch to disable the interface when an invalid LLDP-MED advertisement is received from a neighboring IP phone.
C. Allows an LLDP-MED-enabled switch to forward the advertisements received from a neighboring IP phone on one LAN segment to another segment.
D. Allows an LLDP-MED-enabled switch to request an LLDP-MED advertisement from a neighboring IP phone when a periodic update is not received in a specific interval.
Answer: A

Q: 10 Which statement is correct about the single-secure mode of 802.1X?
A. It does not require any supplicant on the interface; no supplicant is able to gain access.
B. It allows any one supplicant on the interface to be authenticated; once authentication is successful, any other devices on the same interface will gain access.
C. It allows any number of supplicants on the interface to be authenticated; only supplicants with their own successful authentication are allowed access at the same time.
D. It allows any one supplicant on the interface to be authenticated; once authentication is successful, only the successfully authenticated supplicant is allowed access at one time.
Answer: D

Q: 11 What are two features of JUNOS software? (Choose two.)
A. JUNOS facilitates separate control and forwarding planes.
B. All processes use shared memory to make efficient use of available resources.
C. The functionality of JUNOS is made possible through multiple processes that are dependant on each other.
D. All processes run in their own protected memory space to prevent against complete system failure when a single process fails.
Answer: A, D

Q: 12 Which two statements are correct regarding the DHCP snooping feature on EX-series switches? (Choose two.)
A. DHCP snooping forwards DHCPACK messages from DHCP servers on untrusted interfaces.
B. DHCP snooping drops DHCPOFFER messages from DHCP servers on untrusted interfaces.
C. DHCP snooping drops DHCPDISCOVER messages from DHCP clients on trusted interfaces.
D. DHCP snooping treats access ports as untrusted interfaces and trunk ports as trusted interfaces by default.
Answer: B, D

Q: 13 Which statement is true regarding the EX-series file system?
A. The file system must be cleaned manually after every upgrade.
B. The file system must be cleaned manually before every upgrade.
C. Contents in the /var directory are automatically archived for future software rollbacks.
D. Contents in the /var directory are automatically removed upon a successful software upgrade.
Answer: D

Q: 14 When configuring a redundant trunk group (RTG) on an interface, which restriction would apply?
A. The interface cannot be configured as a Layer 2 trunk.
B. The gratuitous-ARP-reply must be disabled on the interface.
C. Spanning Tree Protocol (STP) cannot be configured on the interface.
D. The interface must be configured as a Layer 3 interface with an assigned IP address.
Answer: C

Q: 15 Which statement is true regarding J-Web access?
A. Only HTTP can be used to access J-Web.
B. J-Web access is available only through the me0 interface.
C. J-Web access uses the same authentication method as the CLI.
D. The web-management service is enabled in the factory-default configuration.
Answer: C

Q: 16 Which statement is correct about Dynamic ARP Inspection (DAI)?
A. DAI is configured on a per-port basis.
B. DAI is configured on a Layer 3 interface.
C. DAI requires DHCP snooping to be configured.
D. DAI disables the interface when an incorrect ARP packet is received.
Answer: C

Q: 17 Which command shows the VRRP status for all interfaces?
A. show vrrp
B. show route vrrp
C. show vrrp terse
D. show interfaces vrrp
Answer: A

Q: 18 Click the Exhibit button.

In the exhibit, to which hierarchy level will the user be directed based upon the last command issued?
A. [edit]
root#
B. [edit protocols]
root#
C. [edit protocols ospf]
root#
D. [edit protocols ospf area]
root#
Answer: C

Q: 19 Which two configuration options are valid methods for troubleshooting an EX-series switch? (Choose two.)
A. debug
B. syslog
C. monitor
D. traceoptions
Answer: B, D

Q: 20 Which two major components make up the control and forwarding planes for an EX-series switch? (Choose two.)
A. Routing Engine
B. Switching Engine
C. Switching Fabric Module
D. Packet Forwarding Engine
Answer: A, D

Q: 21 Which bridging mechanism is used to limit traffic to its appropriate VLAN?
A. filtering
B. flooding
C. blocking
D. restricting
Answer: A

Q: 22 Which operational mode command do you use to view the rescue configuration?
A. file list /config/rescue.conf
B. file show /config/rescue.conf
C. file list /config/rescue.conf.gz
D. file show /config/rescue.conf.gz
Answer: D

Q: 23 Which statement is correct when adding a new member switch running software version X to a virtual chassis where the current master switch is running software version Y?
A. Regardless of whether version X is newer than version Y, the new switch joins the virtual chassis running version X while the rest of the members of the virtual chassis run version Y.
B. If the version X is newer than version Y, the current master switch and existing members of the virtual chassis are automatically upgraded to version X and the new switch joins the virtual chassis.
C. Regardless of whether version X is newer than version Y, the new switch joins the virtual chassis
operationally only after its software is upgraded or downgraded to match that of the current master switch.
D. If the version X is newer than version Y, the new switch becomes the new master while the current master switch and existing members of the virtual chassis are automatically upgraded to version X and become the new backup and line card switches.
Answer: C

Q: 24 Which operational-mode command displays the status, physical properties, logical properties, usage statistics, and error statistics for ge-0/0/0?
A. show interfaces ge-0/0/0 brief
B. show interfaces ge-0/0/0 terse
C. show interfaces ge-0/0/0 detail
D. show interfaces ge-0/0/0 extensive
Answer: D

Q: 25 Which two methods are valid for performing a tcpdump on an EX-series interface? (Choose two.)
A. Use the monitor interface traffic command.
B. Use the monitor traffic interface command.
C. Use the packet capture utility under the J-Web Monitor tab.
D. Use the packet capture utility under the J-Web Troubleshoot tab.
Answer: B, D

Q: 26 Click the Exhibit button.

In the exhibit, what does the asterisk (*) indicate?
A. The interface is up and active.
B. The interface is configure for PoE.
C. The interface receives untagged frames.
D. The interface contains Layer 3 configuration.
Answer: A

Q: 27 Click the Exhibit button.

In the exhibit, in which configuration hierarchy would the block-stuff filter be defined?
A. [edit firewall family inet]
B. [edit firewall family vlan]
C. [edit firewall family ethernet]
D. [edit firewall family ethernet-switching]
Answer: D

Q: 28 On an EX-series switch, what information is gathered when building a bridge table? (Choose two.)
A. interface
B. IP address
C. MAC address
D. authentication information
Answer: A, C

Q: 29 What are two software considerations when configuring a link aggregation group? (Choose two.)
A. CPU control packets are sent over the lowest member link within the bundle.
B. Load balancing is enabled by default and does not require any special configuration.
C. If Link Aggregation Control Protocol is used, both devices must be configured for active mode.
D. Load balancing over a link aggregation group must be specifically enabled through configuration.
Answer: A, B

Q: 30 Which switching feature allows individual users to be grouped in a LAN segment based upon business needs?
A. VRRP
B. VLANs
C. 802.1X
D. redundant trunk groups (RTGs)
Answer: B