Configuring IP Addressing

Loopback Interfaces

For more information about how to configure a loopback IP address to participate in an OSPF broadcast area, refer to the section titled “(Optional) Assigning Loopback Addresses to an Area” in the Multicast and Routing Guide.

Configuring a Loopback Interface

To configure a loopback interface, enter the interface loopback command at the global configuration level of the CLI:

Syntax: [no] interface loopback <number>

Creates a loopback interface, where <number> is a value from 1 to 7. Use the no form of the command to remove the loopback interface.

Note: You cannot remove the default loopback interface (number 0) with IP address 127.0.0.1.

 

 

You can configure up to thirty-two IP addresses on a loopback interface. To

 

 

configure an IP address for the loopback interface, enter the ip address < ip­

 

 

address > command at the loopback interface configuration level as shown in

 

 

the following example.

 

 

Note that when you configure an IP address for a loopback interface, you do

 

 

not specify a network mask. The default subnet mask 255.255.255.255 is used.

 

 

 

 

 

ProCurve(config)# interface loopback 1

 

 

ProCurve (lo1)# ip address 10.1.1.1

 

 

Figure 8-6. Example of a Loopback Interface Configuration

 

 

 

N o t e s

 

You can configure a loopback interface only from the CLI; you cannot

 

 

configure a loopback interface from the web management or Menu inter­

 

 

face.

 

 

Loopback interfaces share the same IP address space with VLAN config­

 

 

urations. The maximum number of IP addresses supported on a switch is

 

 

2048, which includes all IP addresses configured for both VLANs and

 

 

loopback interfaces (except for the default loopback IP address

 

127.0.0.1).

 

 

Each IP address that you configure on a loopback interface must be

 

 

unique in the switch. This means that the address cannot be used by a

 

 

VLAN interface or another loopback interface.

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