Extreme Networks ExtremeWare 7.3.0, Command Reference Manual

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360 ExtremeWare Software 7.3.0 Command Reference Guide
FDB Commands
create fdbentry vlan blackhole
create fdbentry <mac_address> vlan <vlan name> blackhole {source-mac |
dest-mac | both}
Description
Creates a blackhole FDB entry.
Syntax Description
Default
N/A.
Usage Guidelines
Blackhole entries are useful as a security measure or in special circumstances where packets with a
specific source or destination address must be discarded.
A blackhole entry configures the switch to discard packets with the specified MAC address. You can
specify whether the MAC address should match the source (ingress) MAC address, or the destination
(egress) MAC address, or both.
Blackhole entries are treated like permanent entries in the event of a switch reset or power off/on cycle.
Blackhole entries are never aged-out of the database. In the output from a
show fdb
command, entries
will have “p” flag (permanent) set, as well as the “b” (for ingress blackhole) and/or “B” (for egress
blackhole) flags set.
Example
The following example adds a blackhole entry to the FDB for MAC address is 00 E0 2B 12 34 56, in
VLAN
marketing on port 4:
create fdbentry 00:E0:2B:12:34:56 vlan marketing both
History
This command was available in ExtremeWare 2.0.
Support for specifying source or destination MAC address was added in ExtremeWare 6.2.
mac_address Specifies a device MAC address, using colon-separated bytes.
vlan name Specifies a VLAN name associated with a MAC address.
blackhole Configures the MAC address as a blackhole entry.
source-mac Specifies that the blackhole MAC address matches the ingress source MAC
address. Support for this parameter was added in ExtremeWare 6.2.
dest-mac Specifies that the blackhole MAC address matches the egress destination
MAC address. Support for this parameter was added in ExtremeWare 6.2.
both Specifies that the blackhole MAC address matches the ingress source MAC
address or the egress destination MAC address. Support for this parameter
was added in ExtremeWare 6.2.