R3166-R3206-HP High-End Firewalls High Availability Configuration Guide-6PW101

101
Table 12 LACP priorities
T
yp
e Descri
p
tion 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 port state accordingly.
The smaller
the priority
value, the
higher the
priority.
Port aggregation
priority
Determines the likelihood of a member port to be selected on a system. The
higher port aggregation priority, the higher likelihood.
Link aggregation modes
There are two link aggregation modes: dynamic and static. Dynamic link aggregation uses LACP while
static link aggregation does not. A link aggregation group operating in static mode is called a static link
aggregation group, while a link aggregation group operating in dynamic mode is called a dynamic link
aggregation group. Table 9 c
ompares the two aggregation modes.
Table 13 A comparison between static and dynamic aggregation modes
Aggregation
mode
LACP status
on member
p
orts
Pros Cons
Static Disabled
Aggregation is stable. The
aggregation state of the member
ports is not affected by their peers.
The member ports cannot
change their aggregation state
in consistent with their peers.
The administrator needs to
manually maintain link
aggregations.
Dynamic Enabled
The administrator does not need to
maintain link aggregations. The peer
systems maintain the aggregation
state of the member ports
automatically.
The aggregation state of
member ports is easily affected
by the network environment,
which makes dynamic
aggregation instable.
In a dynamic link aggregation group:
• A selected port can receive and send LACPDUs.
• An unselected port can receive and send LACPDUs only if it is up and have the same class-two
configurations as the aggregate interface.
Aggregating Links in Static Mode
LACP is disabled on the member ports in a static aggregation group. The aggregation state of the
member ports must be maintained manually.
Static link aggregation comprises:
• Selecting a reference port
• Setting the aggregation state of each member port