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
16-15
Cisco MDS 9000 Family CLI Configuration Guide
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Chapter 16 Configuring PortChannels
PortChannel Protocol
Figure 16-8
Autocreating Channel Groups
The channel group numbers are selected dynamically, and as such, the administrative configuration of
the ports forming the channel group at either end are applicable to the newly created channel group. The
channel group number being chosen dynamically may be different across reboots for the same set of
PortChannels based on the order of ports that are initialized in the switch.
Table 16-2
identifies the differences between user-configured and auto-configured channel groups.
About Autocreation
The autocreation protocol has the following functionality:
1
po10
po20
2
3
4
1
2
3
4
Cisco MDS
Switch A
Cisco MDS
Switch B
Channel Group 10
Channel Group 20
120489
Table 16-2
Channel Group Configuration Differences
User-Configured Channel Group
Autocreated Channel Group
Manually configured by the user.
Created automatically when compatible links come
up between two compatible switches, if channel
group autocreation is enabled in all ports at both
ends.
Member ports cannot participate in autocreation
of channel groups. The autocreation feature
cannot be configured.
None of these ports are members of a
user-configured channel group.
You can form the PortChannel with a subset of the
ports in the channel group. Incompatible ports
remain in a suspended or isolated state depending
on the ON or ACTIVE mode configuration.
All ports included in the channel group participate
in the PortChannel—no member port becomes
isolated or suspended; instead, the member port is
removed from the channel group when the link is
found to be incompatible.
Any administrative configuration made to the
PortChannel is applied to all ports in the channel
group, and you can save the configuration for the
PortChannel interface.
Any administrative configuration made to the
PortChannel is applied to all ports in the channel
group, but the configurations are saved for the
member ports; no configuration is saved for the
PortChannel interface. You can explicitly convert
this channel group, if required.
You can remove any channel group and add
members to a channel group.
You cannot remove a channel group, or add/remove
any of its members. The channel group is removed
when no member ports exist.