Cisco Catalyst 3750-E - Page 972

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Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-08
Chapter 38 Configuring EtherChannels and Link-State Tracking
Configuring Link-State Tracking
Default Link-State Tracking Configuration
There are no link-state groups defined, and link-state tracking is not enabled for any group.
Link-State Tracking Configuration Guidelines
• 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.
• Do not enable link-state tracking on individual interfaces that will be part of a downstream
Etherchannel interface.
• You can configure only two link-state groups per Catalyst 3560-E switch.
• You can configure only ten link-state groups per Catalyst 3750-E switch.
Configuring Link-State Tracking
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 to configure the interfaces:
Switch# configure terminal
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. For
Catalyst 3560-E switches, the group number can be 1 to 2. For
Catalyst 3750-E switches, the group number can be 1 to 10. 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 switch ports in access or trunk mode
(
IEEE 802.1q), routed ports, or multiple ports bundled into an
upstream EtherChannel interface (static, PAgP, or LACP), also in
trunk mode.
Note Do not enable link-state tracking on individual interfaces
that will be part of a downstream Etherchannel interface.
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.For Catalyst
3560-E switches, the group number can be 1 to 2. For Catalyst
3750-E switches, the group number can be 1 to 10. The default is
1.
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.