B&B Electronics 856-14500-01 - Manual User Manual

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Regardless if there is a break in segment 1, 2 or 3, the link will drop on the switches
at both ends.

The link fault is passed through the media conversion and is observed at each end. It
acts just like it would if the devices were directly connected.

NOTE

FiberAlert can also be added to the remote side of the pair to further assist in locating a
fault.

Last Gasp

The iMcV-FiberLinX-II includes a Last Gasp feature, which sends a trap Flinx Unit
Down for the Host unit or a Flinx Remote Unit Down for the Remote unit (as seen in
iView²) when the power to the module fails.

Loopback Testing

The following functions are available during loopback testing. During loopback
testing, management traffic entering the uplink port is still capable of managing the
device. This is selectable form the UNIT screen in a serial/Telnet session. There are
no LoopBack test options in iView²

The menu of choices in the CLI includes:

• No loopback, normal traffic mode
• Loopback Enabled
• Loopback, Source/Destination address swap
• Loopback, address swap and clear Multicast bit

Loopback Testing on Remote or Standalone

Source/Destination Address Swap
A Layer 2 Ethernet switch will discard all received packets with the same MAC
address as sent packets. To avoid this issue the Loopback feature can swap the source
and destination MAC addresses on the looped data. (This selection can cause a frame
with a multicast source address to be created, which violates the IEEE standard.)

Address Swap and Clear Multicast Bit
In addition to swapping the source and destination MAC addresses on the looped
data, the Loopback feature can also be set to clear the multicast bit. This allows the
looped data to avoid being blocked by any multicast settings.