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 refer to the aggregation of multiple physical 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.
This chapter discusses the PortChannel feature provided in the switch and includes the following
A PortChannel has the following functionality:
OL-16184-01, Cisco MDS SAN-OS Release 3.x
About PortChannels, page 16-1
PortChannel Configuration, page 16-6
Interfaces in a PortChannel, page 16-10
PortChannel Protocol, page 16-13
PortChannel Configuration Verification, page 16-17
Default Settings, page 16-20
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
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 25-3
C H A P T E R
Cisco MDS 9000 Family CLI Configuration Guide