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In the topology edit mode, hover your mouse over a switch until you see a cross symbol.
Connect the switch with another switch. Then, you can see an Add Link pop-up window.
In the Ports section, input the connection ports for these two switches.
Click “+” on the right to add a new port connection, or click “-” to remove a port connection. If a selected port is already in use by another link, a warning is displayed.
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