Aggregating Links In Static Mode - H3C SR8800 Configuration Manual

LACP priorities
2.
LACP priorities have the following types: system LACP priority and port aggregation priority, as
described in
Table 10 LACP priorities
Type
System LACP
priority
Port aggregation
priority
LACP timeout interval
3.
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 the short timeout interval (1 second) or the long timeout interval (30
seconds).
Link aggregation modes
Link aggregation has the following modes: dynamic and static. Dynamic link aggregation uses LACP
and static link aggregation does not.
Table 11 A comparison between static and dynamic aggregation modes
Aggregation
mode
Static
Dynamic
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 has 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. You must manually maintain the
aggregation state of the member ports.
Table 10.
Description
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.
Determines the likelihood of a member port to be selected on a system.
The higher port aggregation priority, the higher likelihood.
Table 1 1
LACP status on
Pros
member ports
Aggregation is stable. The
aggregation state of the member
Disabled
ports are not affected by the peer
ports.
The administrator does not need to
maintain link aggregations. The
Enabled peer systems maintain the
aggregation state of the member
ports automatically.
compares the two aggregation modes.
70
Remarks
The smaller the
priority value,
the higher the
priority.
Cons
The member ports do not adjust the
aggregation state according to
that of the peer ports. The
administrator must manually
maintain link aggregations.
Aggregation is unstable. The
aggregation state of member ports
is susceptible to network changes.