HP 12500 SERIES Configuration Manual page 33

LACP MAD handles collisions in a different way than BFD MAD and ARP MAD. To avoid conflicts, do
not enable LACP MAD together with BFD MAD or ARP MAD in an IRF fabric. However, you can use
BFD MAD and ARP MAD together.
Table 1 provides a reference for you to make a MAD mechanism selection decision.
Table 1 A comparison of the MAD mechanisms
MAD
mechanism
LACP MAD
BFD MAD
ARP MAD
Configuring LACP MAD
When you use LACP MAD, follow these guidelines:
The intermediate device must be an HP device that support extended LACP for MAD.
•
If the intermediate device is in an IRF fabric, assign this fabric a different domain ID than the
•
LACP MAD-enabled fabric to avoid false detection of IRF split.
Use dynamic link aggregation mode. MAD is LACP dependent. Even though LACP MAD can be
•
configured on both static and dynamic aggregate interfaces, it takes effect only on dynamic
aggregate interfaces.
Configure link aggregation settings also on the intermediate device.
•
Advantages
• Detection speed is fast.
• Requires no
MAD-dedicated physical
ports or interfaces.
• Detection speed is fast.
•
No intermediate device is
required.
•
Intermediate device, if
used, can come from any
vendor.
•
No intermediate device is
required.
•
Intermediate device, if
used, can come from any
vendor.
•
Requires no MAD
dedicated ports.
Disadvantages
Requires an intermediate
HP device that supports
extended LACP for MAD.
•
Requires MAD
dedicated physical ports
and Layer 3 interfaces,
which cannot be used
for transmitting user
traffic.
•
If no intermediate
device is used, the IRF
members must be fully
meshed.
•
If an intermediate
device is used, every IRF
member must connect
to the intermediate
device.
•
Detection speed is
slower than BFD MAD
and LACP MAD.
• The spanning tree
feature must be
enabled.
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Application scenario
Link aggregation is used
between the IRF fabric
and its upstream or
downstream device.
For information about
LACP, see Layer 2—LAN
Switching Configuration
Guide.
•
Suitable for various
network scenarios.
•
If no intermediate
device is used, this
mechanism is only
suitable for IRF
fabrics that have a
small number of
members that are
geographically close
to one another.
For information about
BFD, see High
Availability
Configuration Guide.
Spanning tree-enabled
non-link aggregation
IPv4 network scenario.
For information about
ARP, see Layer 3—IP
Services Configuration
Guide.