Cisco Catalyst 3560-X Series, Software Configuration Manual

Page: 1038 / 1538

1-24
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-25303-03
Chapter 1 Configuring EtherChannels and Link-State Tracking
Understanding Link-State Tracking
Figure 1-6 Typical Link-State Tracking Configuration
The configuration in Figure 1-6 ensures that the network traffic flow is balanced as follows:
• For links to switches and other network devices
–
Server 1 and server 2 use switch A for primary links and switch B for secondary links.
– Server 3 and server 4 use switch B for primary links and switch A for secondary links.
•
Link-state group 1 on switch A
– Switch A provides primary links to server 1 and server 2 through link-state group 1. Port 1 is
connected to server 1, and port 2 is connected to server 2. Port 1 and port 2 are the downstream
interfaces in link-state group 1.
–
Port 5 and port 6 are connected to distribution switch 1 through link-state group 1. Port 5 and
port 6 are the upstream interfaces in link-state group 1.
141680
Network
Layer 3 link
Server 1 Server 2 Server 3 Server 4
Distribution
switch 1
Distribution
switch 2
Switch A Switch B
Port
1
Port
5
Port
4 Port
3 Port
2 Port
2
Port
3
Port
4
Port
8
Port
7
Port
6
Port
5
Port
1
Port
6
Port
7
Port
8
Link-
state
group 2
Link-state
group 1
Link-state
group 1
Link-state
group 2
Link-state
group 2
Link-
state
group 1
Link-
state
group 1
Primary link
Secondary link
Link-
state
group 2