VRF Flashcards
Virtual Routing and Forwarding
VRF stands for:
Virtual Routing and Forwarding
What is VRF used for
Dividing a single router into multiple virtual routers, similar to VLANs divide a switch into multiple virtual switches
By default, all router interfaces are in the same _____
Routing domain
VRF works by allowing the router to build:
Multiple seperate routing tables
T/F: Only router interfaces, SVIs, and routed ports on multilayer switches can be configured in a VRF
T
T/F: Traffic in one VRF can’t be forwarded out of an interface in another VRF
T
With one exception, VRF leaking can be configured to allow traffic to pass between VRFs. Beyond CCNA scope
What is a primary use of VRF?
Used by service providers to allow one device to carry traffic from multiple customers, and keeping each customer’s traffic isolated from the others
T/F: VRF allows for overlapping IP subnets/IP addresses to all use the same routing appliance
T
T/F: VRF doesn’t allow for overlapping IP subnets/IP addresses to use the same routing appliance
F
This is a primary benefit of VRF
T/F: Without the use of VRF, two interfaces on the same router cannot be in the same subnet
T
What is the command to create a VRF
ip vrf vrf-name
What is the command to show all VRFs on a router
sh ip vrf
What is the command to assign a router interface to a VRF
ip vrf forwarding vrf-name
T/F: If an interface has an IP address configured, the IP address will be removed when the interface is assigned to a VRF
T
T/F: sh ip route displays the global routing table, so if all interfaces are in VRFs, the table will be empty
T
What is the command to view the routing table for a particular VRF
sh ip route vrf vrf-name
You issue the following commands on R1’s g0/0 interface:
~~~
R1(config)# int g0/0
R1(config-if)# ip addr 192.168.1.1 255.255.255.252
R1(config-if)# ip vrf forwarding VRF1
~~~
However, after issuing sh ip int brief you notice g0/0 doesn’t have an IP address. Why?
a) You must use the command ip address 192.168.1.1 255.255.255.252 vrf VRF1
b) The IP address was removed by the ip vrf forwarding VRF1 command
c) You must use sh ip route vrf VRF1 to view the IP address
d) VRF1 doesn’t exist yet
b) The IP address was removed by the ip vrf forwarding VRF1 command
Which of the following statements about VLANs and VRFs are true? (pick 3)
a) VRFs divide routers up by creating separate broadcast domains
b) VLANs divide switches up by creating separate MAC address tables
c) VRFs divide routers up by creating separate routing tables
d) VLANs divide switches up by creating separate broadcast domains
e) VRFs can only be configured on routers
f) Router interfaces in different VRF can have the same IP address
C, D, F
