---
title: "loopback"
slug: "cli-sc-loopback"
updated: 2025-06-30T10:50:48Z
published: 2025-09-03T14:12:28Z
canonical: "docs.crossworkassurance.cisco.com/cli-sc-loopback"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crossworkassurance.cisco.com/llms.txt
> Use this file to discover all available pages before exploring further.

# loopback

## loopback add

loopback add - Add a new loopback configuration

**Description:** loopback add allows you to create a new loopback configurations on remote devices and applicable on both ports. When port name is used, only the port selected supports loopback.

**Syntax:**

```
  loopback add <device-name|port-name> <instance-name> type <jdsu | custom> {
                    { state {enable | disable}} |
                    { loop-up-exp-timeout <decimal}} |
                    { accept-disc-cmd {enable | disable}} |
                    { drop-opposite {enable | disable}} |
                    { filter {l2 | ipv4 | ipv6} <filter-name>} |
                    { port {uni | nni | both}} |
                    { swap_mac {enable | disable}}  |
                    { swap-ip {enable | disable}} |
                    { swap-port {enable | disable}} }+

  <device-name|port-name>       = <string>
  <instance-name>               = <string>
```

**Parameters:**

| Parameter | Description |
| --- | --- |
| device-name | Remote device's name on which loopback is to be added. |
| port-name | Port's name on which loopback is to be added. |
| instance-name | Name of the loopback instance. |
| type | Set loopback type to JDSU or CUSTOM on remote devices. |
| state | Enable or disable the loopback instance. |

**JDSU-Specific Parameters:** (Not valid when PORT NAME is used, JDSU is applicable only when device name is used, cannot be applied on only one port at a time.)

| Parameter | Description |
| --- | --- |
| loop-up-exp-timeout | JDSU Loop Up command expiration timeout period in number of seconds (default value is 60 minutes). |
| accept-disc-cmd | Enable or disable the JDSU discovery command processing on the device. |

**CUSTOM-Specific Parameters:**

| Parameter | Description |
| --- | --- |
| drop-opposite-traffic | Enable or disable dropping of opposite traffic. |
| filter | Specify an associated filter type and name. |
| port | Loopback is tied to port UNI, NNI or both. **Note:** Not applicable when PORT NAME is used. |
| swap-ip | Enable or disable IP address swapping. |
| swap-mac | Enable or disable MAC address swapping. |
| swap-port | Enable or disable port swapping. |

## loopback delete

loopback delete - Delete an existing loopback instance

**Description:** Delete an existing loopback instance.

**Syntax:**

```
  Loopback delete <instance-name>

  <instance-name>          = <string>
```

**Parameters:**

| Parameter | Description |
| --- | --- |
| instance-name | Instance name of the loopback to be deleted. |

## loopback edit

loopback edit - Edit a loopback configuration

**Description:** loopback edit allows you to edit loopback configurations on remote devices.

**Syntax:**

```
  loopback edit <instance-name> {
              { state {enable | disable}} |
              { loop-up-exp-timeout <decimal}} |
              { accept-disc-cmd {enable | disable}} |
              { drop-opposite {enable | disable}} |
              { filter {l2 | ipv4 | ipv6} <filter-name>} |
              { port {uni | nni | both}} |
              { swap_mac {enable | disable}}  |
              { swap-ip {enable | disable}} |
              { swap-port {enable | disable}}}+

  <instance-name>     = <string>
```

**Parameters:**

| Parameter | Description |
| --- | --- |
| instance-name | Name of the loopback instance. |
| state | Enable or disable the loopback instance. |

**JDSU-Specific Parameters:**

| Parameter | Description |
| --- | --- |
| loop-up-exp-timeout | JDSU Loop Up command expiration timeout period in number of seconds (default value is 60 minutes). |
| accept-disc-cmd | Enable or disable the JDSU discovery command processing on the device. |

**CUSTOM-Specific Parameters:**

| Parameter | Description |
| --- | --- |
| drop-opposite-traffic | Enable or disable dropping of opposite traffic. |
| filter | Specify an associated filter type and name. |
| port | Loopback is tied to port UNI, NNI or both. |
| swap-ip | Enable or disable IP address swapping. |
| swap-mac | Enable or disable MAC address swapping. |
| swap-port | Enable or disable port swapping. |

## loopback show

loopback show - Show a loopback configuration

**Description:** loopback show allows you to see the configuration of the loopback.

**Syntax:**

```
  loopback show [<instance-name>]

  <instance-name>          = <string>
```

**Parameters:**

| Parameter | Description |
| --- | --- |
| instance-name | Instance name of loopback to be shown. |

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