Integrated Routing and Bridging (IRB) JN0-281 Practice Questions (Page 3)

Questions 11–14

1. 11expert · hard

   A data center has a pair of QFX5100 switches in a Virtual Chassis. The network team wants to provide Layer 3 routing for VLAN 100 and VLAN 200. They plan to configure IRB interfaces for both VLANs on the Virtual Chassis. Which statement about this configuration is correct?

   • AThe IRB interfaces must be configured on the same member switch to ensure routing works.
   • BThe IRB interfaces are configured on the Virtual Chassis and are active on all member switches.
   • CThe IRB interfaces will not work in a Virtual Chassis because IRB requires a standalone switch.
   • DThe IRB interfaces must be configured on the master switch only.
   Reveal Solution Discussion Select an answer first
2. 12application · medium

   You are configuring IRB on a Juniper EX4300. You have created VLAN 50 and assigned it to interface ge-0/0/10. You then configure 'set interfaces irb unit 50 family inet address 10.10.50.1/24'. However, the IRB interface does not appear as 'up' in the output of 'show interfaces terse'. What is the missing configuration?

   • Aset interfaces ge-0/0/10 unit 0 family ethernet-switching
   • Bset vlans v50 vlan-id 50
   • Cset vlans v50 l3-interface irb.50
   • Dset interfaces irb unit 50 family inet address 10.10.50.1/24
   Reveal Solution Discussion Select an answer first
4. 13application · medium

   A data center has two access switches each carrying VLAN 10 (web servers) and VLAN 20 (application servers). The two switches are connected with a trunk. The web servers on VLAN 10 need to communicate with the application servers on VLAN 20, and the network team wants to minimize the number of Layer 3 gateways to manage. What should you configure to meet this requirement?

   • AConfigure a single IRB interface and associate it with both VLAN 10 and VLAN 20.
   • BConfigure a single IRB interface for VLAN 10 on one switch and a single IRB interface for VLAN 20 on the other switch.
   • CConfigure a Layer 3 subinterface on the trunk link between the two switches for each VLAN.
   • DConfigure IRB interfaces for both VLAN 10 and VLAN 20 on the same switch, and use that switch as the Layer 3 gateway for both VLANs.
   Reveal Solution Discussion Select an answer first
5. 14application · medium

   A host on VLAN 10 sends a packet to a host on VLAN 20. Both VLANs have IRB interfaces configured on the same Juniper switch. How does the switch forward this packet?

   • AThe switch bridges the packet from VLAN 10 to VLAN 20 using the MAC address table.
   • BThe switch drops the packet because IRB interfaces cannot route between VLANs on the same device.
   • CThe switch floods the packet out all ports in VLAN 10 and VLAN 20.
   • DThe switch routes the packet from the IRB interface of VLAN 10 to the IRB interface of VLAN 20, decrementing the TTL.
   Reveal Solution Discussion Select an answer first