B&B Electronics 856-19717--57 - Manual - Manual (Page 11)

8
Loopback Testing
The IE-MiniFiberLinX-II includes Loopback testing functionality. 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 or through
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
• No learning on fiber or Data ports
The menu of choices in iView² includes:
• Off
• ON
• On- Address Swap
• On-Address swap + Clear MC
Loopback Testing on Remote or Standalone
No loopback, normal traffic mode
The standard mode in which the units function, either as stand-alone or
Host/Remote.
Loopback Enabled
Loopback mode without address swap
Loopback, 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.)
Loopback, 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.
Loopback Testing in a Host/Remote configuration