About E Portchannels - Cisco MDS 9000 Series Configuration Manual

About PortChannels
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
PortChannels on Cisco MDS 9000 Family switches allow flexibility in configuration.
illustrates three possible PortChannel configurations:
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This section contains the following topics:
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About E PortChannels

An E PortChannel refers to the aggregation of multiple E ports into one logical interface to provide higher
aggregated bandwidth, load balancing, and link redundancy. PortChannels can connect to interfaces across
switching modules, so a failure of a switching module cannot bring down the PortChannel link.
A PortChannel has the following features and restrictions:
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See the Cisco MDS 9000 Family NX-OS Fabric Configuration Guide for information about failover
Note
scenarios for PortChannels and FSPF links.
Cisco MDS 9000 Family NX-OS Interfaces Configuration Guide
6-2
PortChannel A aggregates two links on two interfaces on the same switching module at each end of
a connection.
PortChannel B also aggregates two links, but each link is connected to a different switching module.
If the switching module goes down, traffic is not affected.
PortChannel C aggregates three links. Two links are on the same switching module at each end,
while one is connected to a different switching module on switch 2.
About E PortChannels, page 6-2
About F and TF PortChannels, page 6-3
About PortChanneling and Trunking, page 6-3
About Load Balancing, page 6-4
About PortChannel Modes, page 6-6
Configuration Guidelines and Restrictions, page 6-7
Provides a point-to-point connection over ISL (E ports) or EISL (TE ports). Multiple links can be
combined into a PortChannel.
Increases the aggregate bandwidth on an ISL by distributing traffic among all functional links in the
channel.
Load balances across multiple links and maintains optimum bandwidth utilization. Load balancing
is based on the source ID, destination ID, and exchange ID (OX ID).
Provides high availability on an ISL. If one link fails, traffic previously carried on this link is switched
to the remaining links. If a link goes down in a PortChannel, the upper protocol is not aware of it. To
the upper protocol, the link is still there, although the bandwidth is diminished. The routing tables
are not affected by link failure. PortChannels may contain up to 16 physical links and may span
multiple modules for added high availability.
Chapter 6 Configuring PortChannels
Figure 6-1
OL-19445-02, Cisco MDS NX-OS Release 4.2(x)