Example for Establishing a Stack Through Service Port Connections Using Dedicated Stack Cables

Networking Requirements

An enterprise network needs to provide sufficient ports for access devices, and the network structure should be simple to facilitate configuration and management.

As shown in Figure 1, Switches A to C set up a stack in a ring topology and connect to SwitchD through an inter-chassis Eth-Trunk. To reduce the configuration, Switches A to C set up a stack using dedicated stack cables. In the stack, SwitchA needs to function as the master switch.

This example describes how to use S5720-LI switches to set up a stack.

Figure 1 Stack topology

Configuration Roadmap

Power off SwitchA, SwitchB, and SwitchC to ensure security.
Connect the switches using dedicated stack cables based on dedicated stack cable connection rules.
Power on SwitchA first to ensure that it becomes the master switch.
Save the stack configuration automatically generated for dedicated cable stacking to the flash memory. This ensures that the stack configuration still takes effect when these cables are removed or other cables are connected.
Configure an inter-chassis Eth-Trunk to increase reliability and uplink bandwidth.

Procedure

Power off SwitchA, SwitchB, and SwitchC.
Connect SwitchA, SwitchB, and SwitchC using dedicated stack cables as shown in Figure 2. Ensure that logical stack port 1 of the local switch is connected to logical stack port 2 of the adjacent switch. Otherwise, these switches cannot set up a stack.
Figure 2 Dedicated stack cable connection
Power on SwitchA, SwitchB, and SwitchC.
# Power on the switches in the following sequence to ensure that SwitchA becomes the master switch.
1. Power on SwitchA first.
2. Power on SwitchB after SwitchA starts.
3. Power on SwitchC after SwitchB starts.

Check whether a stack has been set up successfully.

<SwitchA> display stack
Stack mode: Service-port
Stack topology type : Ring
Stack system MAC: 0018-82d2-2e85
MAC switch delay time: 10 min
Stack reserved vlan : 4093
Slot of the active management port: -- 
Slot     Role        Mac address      Priority   Device type
-------------------------------------------------------------
    0     Master      0018-82d2-2e85   100        S5720-28P-LI-AC
    1     Standby     0018-82c6-1f44   100        S5720-28P-LI-AC
    2     Slave       0018-82c6-1f4c   100        S5720-28P-LI-AC

Save the stack configuration that is automatically generated for dedicated cable stacking to the flash memory.
# After checking that a stack has been set up, save the stack configuration that is automatically generated for dedicated cable stacking to the flash memory.
```
<SwitchA> system-view
[SwitchA] save stack configuration 
Warning: This operation will save all stack configurations to flash. Are you sure you want to continue? [Y/N]:y
```
Configure an inter-chassis Eth-Trunk.
# Configure an inter-chassis Eth-Trunk on uplink ports for the stack. For details, see Example for Configuring Stack Eth-Trunks.

Configuration Files

The stack configuration is written to the flash memory.