Configuring F4 OAM

The ATM interface does not support sending F4 segment loopback cells, but it does respond to F4 segment loopback cells that it receives.

F4 OAM flows need their own channel, and they are identified by the VCI on which they are sent or received. The following VCIs are reserved for F4 OAM flows for each virtual path, and you cannot open PVCs on them:

• VCI 3—For segment F4 flows
• VCI 4—For end-to-end F4 flows

  Note: You cannot enable both loopback cells and CC cells at the same time.

To set up F4 OAM:

1. Enable F4 OAM on an interface or VP. The router enables F4 OAM at the interface level unless you specify a VPI. This example opens both segment and end-to-end F4 OAM circuits on VPI 10.

   host1(config-if)#atm oam 10

2. (Optional) Enable only segment or end-to-end loopback.

   host1(config-if)#atm oam 10 seg-loopback

   host1(config-if)#atm oam 10 end-loopback

3. (Optional) To cause the interface to generate end-to-end loopback cells in addition to receiving and responding to them, set the loopback timer.

   host1(config-if)#atm oam 10 end-loopback loopback-timer 20

4. (Optional) Enable CC cell flows.

   host1(config-if)#atm oam 10 seg-loopback cc source

atm oam

• Use to configure F4 OAM on an interface or circuit. F4 OAM is configured at the interface level unless you specify a VPI.
• To open F4 OAM on either a segment or end-to-end basis, use the following keywords:
  • seg-loopback—Enables F4 segment OAM
  • end-loopback—Enables F4 end-to-end OAM

    Note: If you do not specify either segment or end-to-end loopback, the command applies to both end-to-end and segment F4 OAM circuits.

• To configure CC cell flow on the PVC, use the following keywords:
  • both—Enables the PVC as both the source and the sink endpoints.
  • sink—Enables the PVC as the sink endpoint.
  • source—Enables the PVC as the source endpoint.
  • loopback-timer—When F4 OAM is enabled, the interface or circuit accepts and responds to F4 OAM cells. However, to generate F4 loopback cells, you must configure the loopback timer in the range 1–600 seconds. This timer represents the frequency with which F4 loopback cells are transmitted. You can set the loopback timer only for end-to-end loopback.
• Example 1—Opens both F4 end-to-end and segment OAM circuits for VPI 8

  host1(config-if)#atm oam 8

• Example 2—Opens the F4 end-to-end OAM circuit for VPI 10 and enables sending F4 end-to-end loopback cells on the circuit at a frequency of 20 seconds

  host1(config-if)#atm oam 10 end-loopback loopback-timer 20

• Example 3—Opens both F4 end-to-end and segment OAM circuits on all VPs on this interface

  host1(config-if)#atm oam

• Example 4—Opens F4 segment OAM circuits on all VPs on this interface

  host1(config-if)#atm oam seg-loopback

• Example 5—Opens F4 end-to-end loopback on VPI 12

  host1(config-if)#atm oam 12 end-loopback

• Example 6—Opens an F4 segment OAM circuit for VPI 8 and enables CC cell generation on the segment

  host1(config-if)#atm oam 8 seg-loopback cc source

• Use the no version to delete F4 OAM circuits. Using the options, you can delete all F4 OAM circuits on the interface, segment or end-to-end F4 OAM circuits, or F4 OAM circuits on a specific VPI.
  • Example 1—Deletes all F4 OAM circuits on the interface

    host1(config-if)#no atm oam

  • Example 2—Deletes all F4 segment OAM circuits on the interface

    host1(config-if)#no atm oam segment

  • Example 3—Deletes the F4 end-to-end OAM circuit on VPI 8

    host1(config-if)#no atm oam 8 end-loopback

• See atm oam.

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