HP A3100-16 v2 EI, Configuration Manual

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1.
LACP functions
The IEEE 802.3ad LACP offers basic LACP functions and extended LACP functions, as described in Table
3 .
Table 3 Basic and extended LACP functions
Category Description
Basic LACP functions
Implemented through the basic LACPDU fields, including the system LACP priority,
system MAC address, port LACP priority, port number, and operational key.
Each member port in a LACP-enabled aggregation group exchanges the preceding
information with its peer. When a member port receives an LACPDU, it compares
the received information with the information received on the other member ports. In
this way, the two systems reach an agreement on which ports should be placed in
the Selected state.
Extended LACP
functions
Implemented by extending the LACPDU with new Type/Length/Value (TLV) fields.
This is how the LACP multi-active detection (MAD) mechanism of the Intelligent
Resilient Framework (IRF) feature is implemented. An A3100 v2 switch series can
participate in LACP MAD as either an intermediate device.
2.
LACP priorities
LACP priorities have two types: system LACP priority and port LACP priority.
Table 4 LACP priorities
Type Description Remarks
System LACP
priority
Used by two peer devices (or systems) to determine which one is
superior in link aggregation.
In dynamic link aggregation, the system that has higher system LACP
priority sets the Selected state of member ports on its side first, and then
the system that has lower priority sets the port state accordingly.
Port LACP priority
Determines the likelihood of a member port to be selected on a system.
The higher the port LACP priority, the higher the likelihood.
The smaller the
priority value,
the higher the
priority.
3.
LACP timeout interval
The LACP timeout interval specifies how long a member port waits to receive LACPDUs from the peer port.
If a local member port fails to receive LACPDUs from the peer within three times the LACP timeout interval,
the member port assumes that the peer port has failed. You can configure the LACP timeout interval as
either the short timeout interval (1 second) or the long timeout interval (30 seconds).
Link aggregation modes
Link aggregation has two modes: dynamic and static. Dynamic link aggregation uses LACP and static
link aggregation does not. Table 5 compares the two aggregation modes.
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