AT-9108, AT-8518, AT-8525, and AT-8550 User's Guide
The Blackhole QoS Profile
In the description of various options for configuring Policy-Based
QoS, there is an option to specify blackhole in place of a named
QoS profile. As its name implies, a traffic grouping assigned to the
"blackhole" goes nowhere, and is not forwarded by the switch. There
are noted exceptions. For example, any QoS profile including
blackhole cannot apply to traffic that is normally handled by the
switch management processor, including all ICMP traffic and packets
associated with routing protocols (such as OSPF, RIP, DVMRP, and so
on). The blackhole profile can be used as a flexible security or
performance measure to effectively terminate a particular traffic
grouping.
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