Link Aggregation Example; Link Aggregation Control Protocol Recommendations - IBM 87302RU Planning And Installation Manual

Link aggregation example: As shown in Figure 46, the two LAGs from a
BladeCenter T unit are connected to separate Layer 2 or Layer 3 switches. This
provides a redundant path in case of a link or switch failure.
Typically, the BladeCenter Ethernet switch module ports are attached to one of the
following types of switch:
v A Layer 2 stack switch (1-Gbps ports with a high-speed (10-Gbps) link to a Layer
3 router.
v A Layer 2 or 3 chassis switch with integrated Layer 3 switching or routing. Ports
can be grouped through VLANs.
v A Layer 3 to 7 router or load-balancing switch.
MAC
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MAC
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Figure 46. Recommended network topology with multiport link aggregation groups

Link Aggregation Control Protocol recommendations

LACP exchanges information between a pair of stations on a point-to-point LAG to
ensure proper operation. A communication path is not established unless both
stations are configured correctly and the port-to-port cables are installed on a
subset of configured ports, or on all of the configured ports. For the purpose of this
discussion, the stations are defined as the BladeCenter Ethernet switch ports and
an adjoining Layer 3 external switch. These parameters must be correctly defined
for both stations:
v Define the ports for the LAG and define the group ID.
v Assign the same administrative key to each port within a group.
v Assign a priority to each port within a group (priority can be the same for all
ports).
Multiport aggregation group
1 Gbps or 100 Mbps links
Switch A
L2 Switch
Mgmt
Mod
10/100 Mbps
management
links
Switch B
L2+ Switch
Switch A
Dual
external
switches
Mgmt
Mod
Switch B L2+ Switch
Switch A
Mgmt
Mod
Switch B
Chapter 5. Configuration considerations
IBM Director
- Chassis management
- Application deployment
- Internal switches
Establishment
backbone
Network administrator
- Infrastructure
management
- Network hardware
and software
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