Loopback Interfaces; Using Loopback Interfaces For Source Ip Addresses - Lenovo RackSwitch G8264CS Application Manual

4. At the prompt, enter y to enable the IP interface, or n to leave it disabled:
5. The system prompts you to configure another interface:

Loopback Interfaces

Using Loopback Interfaces for Source IP Addresses

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Enable IP interface? [y/n]
Enter interface number: (1-126)
Repeat the steps in this section until all IP interfaces have been configured. When
all interfaces have been configured, press <Enter> without specifying any interface
number.
A loopback interface provides an IP address, but is not otherwise associated with a
physical port or network entity. Essentially, it is a virtual interface that is perceived
as being "always available" for higher‐layer protocols to use and advertise to the
network, regardless of other connectivity.
Loopback interfaces improve switch access, increase reliability, security, and
provide greater flexibility in Layer 3 network designs. They can be used for many
different purposes, but are most commonly for management IP addresses, router
IDs for various protocols, and persistent peer IDs for neighbor relationships.
In Enterprise NOS 8.4, loopback interfaces have been expanded for use with
routing protocols such as OSPF, PIM, and BGP. Loopback interfaces can also be
specified as the source IP address for syslog, SNMP, RADIUS, TACACS+, NTP, and
router IDs.
Loopback interfaces must be configured before they can be used in other features.
Up to five loopback interfaces are currently supported. They can be configured
using the following commands:
RS 8264CS(config)# interface loopback <1‐5>
RS 8264CS(config-ip-loopback)# [no] ip address <IPv4 address> <mask> enable
RS 8264CS(config-ip-loopback)# exit
The switch can use loopback interfaces to set the source IP addresses for a variety
of protocols. This assists in server security, as the server for each protocol can be
configured to accept protocol packets only from the expected loopback address
block. It may also make is easier to locate or process protocol information, since
packets have the source IP address of the loopback interface, rather than numerous
egress interfaces.
Configured loopback interfaces can be applied to the following protocols:
 Syslogs
RS 8264CS(config)# logging source-interface loopback <1‐5>
SNMP traps

RS 8264CS(config)# snmp-server trap-source loopback <1‐5>
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Chapter 2: Initial Setup