3Com 5104M-FL1 installation and operation guide Remote Failure Signaling

Remote Failure Signaling

In any redundant link path, you can designate (that is, activate) only one end as a redundant port pair (1-2 or 3-4). You must enable remote failure signaling (RFS) if ports are connected to fiber with redundancy enabled at the other end. If you enable ports at both ends as redundant, or if you do not enable remote failure signaling at the distant end, improper operation of the redundant switchover mechanism occurs (see Figure 2-11).

If the primary link experiences a local or remote fault, the backup link activates and the primary ports disconnect (that is, they do not pass data to and from the concentrator). Once the switchover to backup occurs, the redundancy status indicators blink at the redundant module end. However, primary port diagnostics continue to operate. If the fault clears, the primary port is re-enabled.

Each redundancy status LED (located beneath the Activity LEDs):

❑Is off - If you disable redundancy.

❑Is on - If you enable redundancy and both ports are operational.

❑Blinks - If a switchover occurs due to a link failure.

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