How to Configure Stacking - DGS-3120-Series
This document is to achieve stacking of several units. Please note that the maximum units that can be stacked are 6 switches of the same family and the switch has two ports for stacking allowing it to use stack in ring topology.
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A chain stacking topology allows a maximum bandwidth of up to 20Gbps stacking, where as a closing the ring can reach up to maximum bandwidth of 40Gbps stacking.
Stacking:
Step 1 - Enter the configuration of the Switch through your browser by entering the IP address of the switch, default IP address is 10.90.90.90 so you will need to enter http://10.90.90.90
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The default password is:
User: admin
Password: admin
Step 2 - Once inside the switch configuration go to:
System Configuration > Stacking > Stacking Mode Settings
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Step 3 - Within the "Stacking Mode Settings" activate "Stacking Mode" setting the option to "Enabled" and clicking “Apply”.
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• After applying the configuration click the "Save" option in the top menu
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Save Configuration /Log
Type mark in the "ALL" option and click “Apply” to save the changes.
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Step 4 - Turn on the Stacking in each of the switches, each are assigned automatically an ID and the role of "Master", if you want to force the state of "Master" to a particular switch, check only on that switch the option "Force master role" and if you also want to specify a different stack ID for each unit, the lower priority will not change the ID only indicate the order in which the role of master performed if the master is removed.
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Remember once the settings are saved from the top menu as noted above.
Save Configuration /Log
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A chain stacking topology allows a maximum bandwidth of up to 20Gbps stacking, where as a closing the ring can reach up to maximum bandwidth of 40Gbps stacking.
Stacking:
Step 1 - Enter the configuration of the Switch through your browser by entering the IP address of the switch, default IP address is 10.90.90.90 so you will need to enter http://10.90.90.90

The default password is:
User: admin
Password: admin
Step 2 - Once inside the switch configuration go to:
System Configuration > Stacking > Stacking Mode Settings
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Step 3 - Within the "Stacking Mode Settings" activate "Stacking Mode" setting the option to "Enabled" and clicking “Apply”.
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• After applying the configuration click the "Save" option in the top menu
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Save Configuration /Log
Type mark in the "ALL" option and click “Apply” to save the changes.
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Step 4 - Turn on the Stacking in each of the switches, each are assigned automatically an ID and the role of "Master", if you want to force the state of "Master" to a particular switch, check only on that switch the option "Force master role" and if you also want to specify a different stack ID for each unit, the lower priority will not change the ID only indicate the order in which the role of master performed if the master is removed.
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Remember once the settings are saved from the top menu as noted above.
Save Configuration /Log
These may also help:
- Why doesn’t my DGS-3120 Series Stack work? Read Answer