Wendell odom

show ip route
^
% Invalid input detected at '^' marker.
SW3# 
configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
SW3(config)# 
ip routing
^
% Invalid input detected at '^' marker.
9780135792735_book.indb 404
9780135792735_book.indb 404
7/25/19 2:45 PM
7/25/19 2:45 PM

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17
Chapter 17: IP Routing in the LAN 405
The second big area to investigate when troubleshooting SVIs relates to the SVI state, a state 
that ties to the state of the associated VLANs. Each VLAN interface has a matching VLAN 
of the same number, and the VLAN interface’s state is tied to the state of the VLAN in cer-
tain ways. In particular, for a VLAN interface to be in an up/up state:
Step 1.
The VLAN must be defined on the local switch (either explicitly or learned 
with VTP).
Step 2.
The switch must have at least one up/up interface using the VLAN, either/both:
A.
An up/up access interface assigned to that VLAN
B.
A trunk interface for which the VLAN is in the allowed list, is STP forward-
ing, and is not VTP pruned
Step 3.
The VLAN (not the VLAN interface) must be administratively enabled (that is, 
not 
shutdown
).
Step 4.
The VLAN interface (not the VLAN) must be administratively enabled (that is, 
not 
shutdown
).
When working through the steps in the list, keep in mind that the VLAN and the VLAN 
interface are related but separate ideas, and the configuration items are separate in the CLI. 
The VLAN interface is a switch’s Layer 3 interface connected to the VLAN. If you want to 
route packets for the subnets on VLANs 11, 12, and 13, the matching VLAN interfaces must 
be numbered 11, 12, and 13. And both the VLANs and the VLAN interfaces can be disabled 
and enabled with the