Cisco Catalyst 4500 Series - Determining if no Form of Commands Appear in Configuration Files

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 83 Configuring Easy Virtual Network
About Easy Virtual Network
When the following commands are entered, the OSPF cost value is restored to 20, which is the cost
inherited from the trunk interface. (Note that 20 is not the default value of the ip ospf cost command.)
Device(config-if)# vnet name blue
Device(config-if-vnet)# default ip ospf cost
Determining if No Form of Commands Appear in Configuration Files
If a command switches a feature on or off, the no form of the command appears in the configuration file
when configured. Nonvolatile generation (NVGEN) overrides the setting from the EVN trunk, as shown
in the following example:
interface gigabitethernet 2/0/0
vnet trunk
vnet name red
no ip pim sparse-mode
no ip route-cache cef
vnet global
ip ospf cost 100
If a command takes an argument in its syntax, such as ip ospf cost cost , the no form of the command
will remove the configuration, but does not appear in the configuration file. That is, it will not be
NVGEN’ed because the user could enter ip ospf cost default-value to override the inherited value.
EVN Compatibility with VRF-Lite
EVN is wire compatible with VRF-Lite. In other words, on the outside, 802.1q, SNMP MIBs, and all the
EVN infrastructure will look exactly the same as VRF-Lite.
In the figure below, both devices have VRFs defined. The device on the left uses VRF-Lite, and the
device on the right uses an EVN trunk with tags. The two configurations follow the figure.
Example: VRF-Lite Subinterface Configuration EVN Trunk Configuration
interface TenGigabitEthernet1/1/1 interface TenGigabitEthernet 1/1/1
ip address 10.122.5.31 255.255.255.254 vnet trunk
ip pim query-interval 333 msec ip address 10.122.5.32 255.255.255.254
ip pim sparse-mode pim sparse-mode
logging event link-status logging event link-status
interface TenGigabitEthernet1/1/1.101 Global Configuration:
description Subinterface for Red VRF vrf definition red
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