Displaying loopback interface configurations

Do one of the following:

  • Use the show ip command to display a list of the loopback interfaces, which are sorted according to the loopback number.

    The list of loopback interfaces is displayed below other IP configuration parameters, such as packet TTL and ARP age-out values, and VLAN IP configurations. The default loopback interface (

  • Use the show ip route command to display the loopback interfaces in a list of IP routing entries. The list is sorted according to the destination IP address.

Examples

The following example displays the IP addresses configured for two user-defined loopback interfaces(lo1 and lo2). 


switch# show ip

 IP Routing : Enabled

   Default Gateway : 15.255.128.1
   Default TTL     : 64
   Arp Age         : 20
   Domain Suffix   :
   DNS server      : 

                    |                                           Proxy ARP
   VLAN             | IP Config  IP Address      Subnet Mask    Std Local
   ---------------- + ---------- --------------- -------------- ----------
   DEFAULT_VLAN     | Manual     10.0.8.121     255.255.0.0     No   No
   VLAN2              Manual     192.168.12.1   255.255.255.0   No   No
   VLAN3              Disabled


                           Loopback Addresses
   Loopback   IP Config    IP Address           Subnet Mask
   --------   ----------   ------------------   ---------------
   lol        Manual       172.16.110.2         255.255.255.255 
   lo2        Manual       172.16.112.2         255.255.255.255 
   lo2        Manual       172.16.114.1         255.255.255.255
The following example displays the configuration of the default loopback interface (lo0) and one user-defined loopback interface (lo2). 

switch# show ip route

                                IP Route Entries

Destination        Gateway         VLAN Type      Sub-Type   Metric    Dist.
------------------ --------------- ---- --------- ---------- --------- ----
10.0.0.0/16        DEFAULT_VLAN    1    connected             1         0
127.0.0.0/8        reject               static                0         0
127.0.0.1/32       lo0                  connected             1         0
172.16.10.121/32   lo2                  static                1         0
172.16.100.0/24    10.0.8.11       1    ospf       IntraArea  1         1
172.16.102.0/24    VLAN2           2    connected             1         0