Dell PowerConnect B-FCXs, Руководство по настройке

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PowerConnect B-Series FCX Configuration Guide 413
53-1002266-01
Dynamic link aggregation
12
FastIron Stackable devices
The following notes and feature limitations apply to the PowerConnect B-Series FCX devices.
•
The dynamic link aggregation (802.3ad) implementation allows any number of ports up to
eight to be aggregated into a link.
•
The default key assigned to an aggregate link is based on the port type (1 Gbps port or 10
Gbps port). The device assigns different keys to 10 Gbps ports than on 1 Gbps ports so that
ports with different physical capabilities will not be able to form a trunk.
NOTE
The trunks that will be formed by link aggregation will strictly adhere to the static trunking rules
on the Stackable devices. Be careful in selecting keys if you are manually configuring link
aggregation keys. Make sure that the possible trunks that you expect to be formed conform to
the static trunking rules.
•
When you enable link aggregation (LACP) on a group of Dell PowerConnect ports, you must also
assign a unique key (other than the default key) to all of the ports in the aggregate link.
•
10 Gbps links only support two port trunks.
FastIron Stackable devices in an IronStack
•
If a stack unit fails, or is removed from the stack, its LACP configuration becomes a reserved
configuration on the Active Controller. Any remaining ports of the dynamic trunk in the
IronStack continue to function.
•
Merging two IronStacks with a dynamic trunk configured between them results in self-looped
ports, which are detected and corrected by the Spanning Tree Protocol (STP). LACP
configuration on the winning Active Controller is not affected by the LACP configuration on the
losing Active Controller is lost after the merge.
•
When an IronStack with dynamic trunks partitions into multiple IronStacks, the protocol will
take care of splitting the dynamic trunk in the partner. No user intervention is required.
Adaptation to trunk disappearance
The Dell PowerConnect device will tear down an aggregate link if the device at the other end of the
link reboots or brings all the links down. Tearing the aggregate link down prevents a mismatch if the
other device has a different trunk configuration following the reboot or re-establishment of the
links. Once the other device recovers, 802.3 can renegotiate the link without a mismatch.
Flexible trunk eligibility
The criteria for trunk port eligibility in an aggregate link are flexible. A range of ports can contain
down ports and still be eligible to become an aggregate link.
The device places the ports into 2-port groups by default, consisting of an odd-numbered port and
the next even-numbered port. For example, ports 1/1 and 1/2 are a two-port group, as are ports
1/3 and 1/4, 9/1 and 9/2, and so on. If either of the ports in a two-port group is up, the device
considers both ports to be eligible to be in an aggregate link.