Subinterfaces

Question about subinterfaces.

when configuring subinterfaces, the following commands are used.

int fa0/0
no ip address
no shut

int fa0/0.1
ip address 172.16.10.1 255.255.255.0

int fa0/0.2
ip address 172.16.20.1 255.255.255.0

Is there a way to shutdown (1) subinterface with out shutting down the entire Fa0/0 port? For example: i want to shut down fa0/0.2, but keep fa0/0.1 up.

Thank you,

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Comments

mikearama

and

<config>#int fa0/0.2
<config-int>#shut

didn't work?

datchcha

don't know, not at my lab right now...working on a Navision sql backup and passing my time.

Mikdilly

How do you remove multipoint from a sub-interface?

R2#show run
Building configuration...

Current configuration : 1028 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname R2
!
!
!
interface Serial1/0
no ip address
encapsulation frame-relay
serial restart-delay 0
frame-relay lmi-type ansi
!
interface Serial1/0.1 multipoint
!
interface Serial1/1
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/2
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/3
no ip address
shutdown
serial restart-delay 0
!
router ospf 65
log-adjacency-changes
network 140.1.0.0 0.0.255.255 area 0
--More--

Tried changing to: int s1/0.1 point-to-point
and get: % Warning: cannot change link type

mikej412

I don't think you can change it without a reload.

Use the "no" version of the command to get rid if the current sub-interface -- then reload. Then configure the point-to-point version of that sub-interface.

keenon

datchcha wrote:

Question about subinterfaces.

when configuring subinterfaces, the following commands are used.

int fa0/0
no ip address
no shut

int fa0/0.1
ip address 172.16.10.1 255.255.255.0

int fa0/0.2
ip address 172.16.20.1 255.255.255.0

Is there a way to shutdown (1) subinterface with out shutting down the entire Fa0/0 port? For example: i want to shut down fa0/0.2, but keep fa0/0.1 up.

Thank you,

per this posting..

you will need to choose an encapsulation under the subinterfaces and its very good to set the speed and duplex on both sides of the trunk link.

per your other question about shutting down a certain subinterface without taking down another .. yes you can