FireBrick FB6402, Руководство пользователя

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MAC Addresses usage
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B.2.5. Running out of MACs
The allocations are recorded in persistent data, so if an object is removed from the config and later put back
it should get the same MAC address. If however there are not enough MAC addresses when loading a config,
then previous assignments are re-used. If there are too many interface, subnet and ppp objects within the config
to allocate MAC addresses (even reusing old allocations) then an error is given and the config cannot be loaded.
Tip
Using restrict-mac on an interfaces restricts that interface (port group/VLAN) to only use one
MAC and not one per subnet.
B.3. MAC address on label
The label attached to the bottom of the FB6000 shows what MAC address range that unit uses, using a compact
notation, as highlighted in Figure B.1 :-
Figure B.1. Product label showing MAC address range
In this example, the range is specified as :-
000397:147C-F
this is interpreted as :-
• All addresses in the range start with
00:03:97:14:7
• the next digit then ranges from "C" through to "F"
• the first address in the range has zero for the remaining digits (
C:00
)
• the last address in the range has F for the remaining digits (
F:FF
)
Therefore this range spans
00:03:97:14:7C:00
to
00:03:97:14:7F:FF
inclusive (1024 addresses).
If you trying to identify an IP address allocation, note that the exact address used within this range depends
on a number of factors ; generally you should look for an IP address allocation against any of the addresses
in the range.
Alternatively, if the range specification doesn't include a hyphen, it specifies that all addresses in the range start
with this 'prefix' - the first address in the range will have zero for all the remaining digits, and the last address
in the range will have F for all the remaining digits. For example :-
000397:147C
is interpreted as :
• All addresses in the range start with 00:03:97:14:7C