Cisco Systems DSC9148D8G48PK9 manual Channel Group Creation, Autocreating Channel Groups

Chapter 6 Configuring PortChannels

Information About PortChannels

The PortChannel protocol is enabled by default.

The PortChannel protocol expands the PortChannel functional model in Cisco MDS switches. It uses the exchange peer parameters (EPP) services to communicate across peer ports in an ISL. Each switch uses the information received from the peer ports along with its local configuration and operational values to decide if it should be part of a PortChannel. The protocol ensures that a set of ports are eligible to be part of the same PortChannel. They are only eligible to be part of the same PortChannel if all the ports have a compatible partner.

The PortChannel protocol uses two subprotocols:

•Bringup protocol—Automatically detects misconfigurations so you can correct them. This protocol synchronizes the PortChannel at both ends so that all frames for a given flow (as identified by the source FC ID, destination FC ID and OX_ID) are carried over the same physical link in both directions. This helps make applications such as write acceleration, work for PortChannels over FCIP links.

•Autocreation protocol—Automatically aggregates compatible ports into a PortChannel.

This section describes how to configure the PortChannel protocol and includes the following sections:

•Channel Group Creation, page 6-10

•Autocreation, page 6-11

•Manually Configured Channel Groups, page 6-12

Channel Group Creation

Note Channel groups are not supported on internal ports in the Cisco Fabric Switch for HP c-Class BladeSystem and the Cisco Fabric Switch for IBM BladeSystem.

Assuming link A1-B1 comes up first (see Figure 6-6), that link is operational as an individual link.When the next link comes up, for example, A2-B2, the PortChannel protocol identifies if this link is compatible with link A1-B1 and automatically creates channel groups 10 and 20 in the respective switches. If link A3-B3 can join the channel groups (the PortChannels), the respective ports have compatible configurations. If link A4-B4 operates as an individual link, it is because of the incompatible configuration of the two end ports with the other member ports in this channel group.

Figure 6-6 Autocreating Channel Groups

Channel Group 10 Channel Group 20

Cisco MDS

Switch A

1 po10 po20

2

3

4

1

2

Cisco MDS 3 Switch B

4 120489

	Cisco MDS 9000 Family NX-OS Interfaces Configuration Guide
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