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Cisco Catalyst Blade Switch 3020 for HP Software Configuration Guide
OL-8915-03
Chapter 33 Configuring EtherChannels and Layer 2 Trunk Failover
Understanding Layer 2 Trunk Failover
Layer 2 Trunk Failover Configuration Guidelines
Follow these guidelines to avoid configuration problems:
•
Do not configure a cross-connect interface (gi0/23 or gi0/24) as a member of a link-state
group.
•
Do not configure an EtherChannel as a downstream interface.
•
Only interfaces gi0/1 through gi0/16 can be configured as downstream ports in a specific link-state
group.
•
Only interfaces gi0/17 through gi0/24 can be configured as upstream ports in a specific link-state
group.
•
An interface that is defined as an upstream interface cannot also be defined as a downstream
interface in the same or a different link-state group. The reverse is also true.
•
An interface cannot be a member of more than one link-state group.
•
You can configure only two link-state groups per switch.
Configuring Layer 2 Trunk Failover
Beginning in privileged EXEC mode, follow these steps to configure a link-state group and to assign an
interface to a group:
This example shows how to create a link-state group and configure the interfaces:
Switch#
configure terminal
Switch(config)#
link state track 1
Switch(config)#
interface range gigabitethernet0/21 - 22
Switch(config-if)#
link state group 1 upstream
Switch(config-if)#
interface gigabitethernet0/1
Switch(config-if)#
link state group 1 downstream
Switch(config-if)#
interface gigabitethernet0/3
Switch(config-if)#
link state group 1 downstream
Switch(config-if)#
interface gigabitethernet0/5
Switch(config-if)#
link state group 1 downstream
Switch(config-if)#
end
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
link state track
number
Create a link-state group, and enable link-state tracking. The
group number can be 1 or 2; the default is 1.
Step 3
interface
interface-id
Specify a physical interface or range of interfaces to configure,
and enter interface configuration mode.
Valid interfaces include physical ports in access or trunk mode
(IEEE 802.1q) or multiple physical ports bundled into an
EtherChannel interface (static or LACP), also in trunk mode.
Step 4
link state group
[
number
] {
upstream
|
downstream
}
Specify a link-state group, and configure the interface as either
an
upstream
or
downstream
interface in the group.
Step 5
end
Return to privileged EXEC mode.
Step 6
show running-config
Verify your entries.
Step 7
copy running-config startup-config
(Optional) Save your entries in the configuration file.
