To set up a local loopback, complete the following tasks:
- Define filters to capture traffic (required for Custom loopbacks only). See "Defining Filters".
- Create an OAM instance. See "Setting Up an OAM Instance".
- Create the loopback.
To set up a local loopback
-
Choose OAM ► Loopback.
The page displays a summary of the configured OAM instances.
-
Click the instance Name.
-
Enter values in the required fields (at the top of the page), and then click Apply.
Note: If you select Loopback enable or Drop opposite traffic, the system displays a confirmation message. Click OK to continue or Cancel to return to the previous screen.
For more information about specific parameters, see the following table.
Note: For a local loopback, only the fields listed in the following table are required. Leave all other fields at their default settings.
Loopback (Loopback ► Configuration)
| Parameter | Description |
|---|---|
| Name | OAM instance name, as defined on the OAM ►Configuration page. |
| Port | Port on which to create the loopback. |
| State | Current loopback state. An enabled loopback does not always loop traffic; behavior depends on the location setting. A remotely controlled loopback instance does not display in this field. |
| Lpbk Mode | When loopback control logic is enabled, this field displays the selected loopback mode for the port. This parameter is always set to Private. Private indicates that no 802.3ah loopback is active or that a private (proprietary) loopback is configured. In private loopback mode, you can select filters or preset OEM loopback types. This creates an in-service loopback that allows other traffic to pass through. |
| Location | Indicates whether the loopback is controlled locally or remotely. When enabled, a local loopback applies immediately, based on the configured settings. When enabled, a remote loopback instructs the unit to send a loopback request to its OAM partner. |
| Loopback enable | Select to activate a locally controlled loopback, and then select a Type. Note: Do not select this check box to activate a remote loopback. To configure a remote loopback, use Remote loopback enable. |
| Type | Loopback type:
|
| Persistent | Enables the loopback at system startup. Note: This option applies only to locally controlled loopbacks with no timeout. |
| Filter type | Filter type for loopback traffic:
|
| L2 filter | L2 filter to apply to loopback traffic when Filter type is L2 filter. |
| IPv4 filter | IPv4 filter to apply to loopback traffic when Filter type is IPv4 filter. |
| IPv6 filter | IPv6 filter to apply to loopback traffic when Filter type is IPv6 filter. |
| Actions | One or more actions:
|
| Drop opposite traffic | Enables or disables dropping of opposite traffic. Warning: Drop-opposite traffic will drop all the traffic entering the device on the opposite port. |
| Loopback timeout (minutes) | Number of minutes that the loopback remains enabled. When the timeout expires, the unit terminates the loopback automatically. |
Remote loopback enable
| Parameter | Description |
|---|---|
| JDSU/Acterna™ | Select to indicate that the remote loopback is controlled by a JDSU/Acterna™ device. |
| Enable discovery loop commands | Select to accept JDSU/Acterna™ discovery loopback commands. |
| Sunrise™ | Select to indicate that the remote loopback is controlled by a Sunrise™ device. The unit supports Layer 2 and Layer 3 tests. |
| VeEX™ | Select to indicate that the remote loopback is controlled by a VeEX™ device. The unit supports Layer 2, Layer 3, and Layer 4 tests. |
| OAM 802.3ah | Select to indicate that the remote loopback is controlled by a device that supports the OAM 802.3ah protocol. |
| Accept tagged loopback commands | Select to accept tagged loopback commands. This option is valid only for untagged OAM instances. Tagged OAM instances accept loopback commands only from a specific VLAN. |
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