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This section describes how to configure and use user-defined loopback interfaces on the switch.
NOTE: The interface loopback command is not support by HP Switch 2530 (J9772A–J9783A) products. |
Imagine you have 10 3750X switches, you can connect the out of band port from each switch to another switch and give the out of band port an IP address. So: example: switch-1 10.10.10.1/24. Switch-2 10.10.10.2/24. Switch-10 10.10.10.10/24. On the collection switch you create vlan 50. Ip add 10.10.10.100/24. Loopback interfaces do not have internal VLAN IDs or MAC addresses. With Layer 2 Cisco switches like the 3500XL or 2950, a loopback interface is not needed since these switches are not capable of.
Important: If you’re new to LoopBack, use the current release, LoopBack 4.0. To ask questions and discuss how you are using LoopBack, check out the LoopBack Developer Forum. Note: IBM API Connect is an end-to-end API management solution that uses LoopBack to create APIs, and provides integrated build and deployment tools. To move your app from LoopBack 2.x to 3.x, edit the package.json file, then install dependencies from npm. Edit package.json. Make the following changes to your app’s package.json file: Change the dependency on loopback to specify version 3.0. Remove loopback-datasource-juggler from dependencies, since it is now a regular dependency. 3.5k votes, 275 comments. 459k members in the techsupportgore community. Your school should enable loopback detection on the switches.
By default, each switch has an internal loopback interface (
lo0
) with the IP address 127.0.0.1. This IP address is used only for internal traffic transmitted within the switch and is not used in packet headers in egress traffic sent to network devices.You can configure up to seven other loopback interfaces (
lo1
, lo2
, lo3
, and so on) on the switch to use to transmit network across the network. Each loopback interface can have multiple IP addresses. Routing protocols, such as RIP and OSPF, advertise the configured loopback addresses throughout a network or autonomous system.User-defined loopback addresses provide the following benefits:
- A loopback interface is a virtual interface that is always up and reachable as long as at least one of the IP interfaces on the switch is operational. As a result, a loopback interface is useful for debugging tasks since its IP address can always be pinged if any other switch interface is up.
- You can use a loopback interface to establish a Telnet session, ping the switch, and access the switch through SNMP, SSH, and HTTP (WebAgent).
- A loopback IP address can be used by routing protocols. For example, you can configure the loopback IP address as the router ID used to identify the switch in an OSPF area. Because the loopback interface is always up, you ensure that the switch's router ID remains constant and that the OSPF network is protected from changes caused by downed interfaces.
NOTE: OSPF does not require that you use an IP address as the router ID. OSPF only requires the router ID to be a unique value within the autonomous system (AS). However, if you configure the loopback IP address as the router ID, OSPF can reach the switch if any switch interface is up. (Normally, OSPF automatically configures the router ID with the IP address of a switch interface. The disadvantage is that if the interface goes down, OSPF can no longer ping the switch using the router ID even if other interfaces are operational.) For more information about how to configure a loopback IP address to participate in an OSPF broadcast area, See the section titled '(Optional) Assigning Loopback Addresses to an Area' in the Multicast and Routing Guide. |
Vlc media player 3 0 8 portable. NOTE: The interface loopback command is not support by HP Switch 2530 (J9772A–J9783A) products. |
To configure a loopback interface, enter the interface loopback command at the global configuration level of the CLI:
Syntax
Creates a loopback interface, where<number> is a value from 1 to 7. Use thenoform 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.
NOTE:
|
To display the list of loopback interfaces which have been assigned IP addresses, enter the show ip command.
In the show ip command output, information about configured loopback interfaces is displayed below other IP configuration parameters, such as packet TTL and ARP age-out values, and VLAN IP configurations. The following example displays the IP addresses configured for two user-defined loopback interfaces (lo1) and (lo2).
The show ip command output
NOTE: The default loopback interface ( lo0 ) with IP address 127.0.0.1 is not displayed in the show ip command output because it is permanently configured on the switch. To display the default loopback address, enter theshow ip route command as shown in the example below. |
To display the loopback interfaces configured on the switch in a list of IP routing entries displayed according to destination IP address, enter the show ip route command.
Mplayerx – alternative media player. The following example displays the configuration of the default loopback interface (lo0) and one user-defined loopback interface (lo2).
Loopback 2 1 3 Switch Wiring
2 1/3 Fraction
The show ip route command output