FCM9002 USER MANUAL
76-02-095 Rev.B
Page 132 of 145
For example, assume that the MAC address of the target FCM9002 has been
discovered and is 00:C0:81:00:1F:3C. This may be converted to a magic
address by setting bit 23, to become 00:C0:81:80:1F:3C. Test frames may now
be sent to the target with the destination set to 00:C0:81:80:1F:3C and they will
be looped back automatically.
4.7.2.2.4 User Port(s)
Any frame ingressing the selected User ports with a “magic” address will be
looped back regardless provided a flow, of which it is a member, is configured for
the port..
There are two “magic” addresses supported by the FCM9002 User ports
4.7.2.2.5 Well Known “Magic” Address
00:C0:81:FF:00:01
This is common to all Metrodata MetroConnect
devices that support DA/SA swap loopback
and as such may be used as the destination
address for loopback from any unit.
4.7.2.2.6 Device Specific Loopback Address
In some networks, the use of the common, well known target address may cause
problems due to the same address seeming to reside in many different locations
due to the DA/SA swapping function. If this is the case, then a device specific
loopback address may be used, however this requires knowledge of the MAC
address of the target unit. Once the target MAC address is discovered, then the
“magic” address is generated by setting bit 22 of the MAC. The example below
shows this in practice.
For example, assume that the MAC address of the target FCM9002 has been
discovered and is 00:C0:81:00:1F:3C. This may be converted to a magic
address by setting bit 22, to become 00:C0:81:40:1F:3C. Test frames may now
be sent to the target with the destination set to 00:C0:81:40:1F:3C and they will
be looped back automatically.
