Loopback Interface

Loopbacks are essentially internal virtual interfaces. Loopback interfaces are not bound to a physical port and are used for device management and routing protocols.

Configuration Commands

switch(config)# interface loopback LOOPBACK
switch(config-loopback-if)# ip address IP-ADDR/<SUBNET|PREFIX>

Example Output

switch(config)# interface loopback 1
switch(config-loopback-if)# ip address 99.99.99.1/32
switch(config-loopback-if)# end
show run interface loopback1
interface loopback1
   no shutdown
   ip address 99.99.99.1/32
   exit
show ip interface loopback1
Interface loopback1 is up
 Admin state is up
 Hardware: Loopback
 IPv4 address 99.99.99.1/32

Expected Results

  1. Administrators can create a loopback interface
  2. Administrators can give a loopback interface an IP address
  3. Administrators can validate the configuration using the show commands.

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