C H A P T E R 23 Configuring Portchannels; About E Portchannels - Cisco AP775A - Nexus Converged Network Switch 5010 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 physical Ethernet interfaces 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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Note See the
scenarios.
Cisco MDS 9000 Family Fabric Manager Configuration Guide
23-2
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 23-2
About F and TF PortChannels, page 23-3
About PortChanneling and Trunking, page 23-3
About Load Balancing, page 23-4
About PortChannel Modes, page 23-6
Configuration Guidelines and Restrictions, page 23-7
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.
"Fail-Over Scenarios for PortChannels and FSPF Links" section on page 32-3
Chapter 23 Configuring PortChannels
Figure 23-1
for failover
OL-17256-03, Cisco MDS NX-OS Release 4.x