Daisy-Chaining Network Switches
If a single switch doesn’t have enough ports for your entire network, you can connect switches together by daisy-chaining them. On older switches, you sometimes had to use special cables (called crossover cables) or designated ports (called uplink ports) to daisy-chain switches together. Modern switches don’t require this extra consideration. Instead, you can daisy-chain two switches simply by connecting any port on the first switch to any port on the second switch.
Note that you should not chain more than three switches together. You can get around this rule by using stackable switches. Stackable switches have a special type of cable connector that connects two or more switches in a way that lets them function as if they were a single switch. Stackable switches are a must for large networks.
When you daisy-chain switches, be careful to avoid creating a loop. For example, suppose you have three switches, called SW1, SW2, and SW3. If you daisy-chain SW1 to SW2, and then daisy-chain SW2 to SW3, and then finally daisy-chain SW3 to SW1, you will have created a loop. When that happens, all insanity will break loose and your network will grind to a halt.
(A good reason to use managed switches instead of inexpensive consumer-grade switches is that managed switches can detect such loops and quickly shut them down.)