Which port and protocol is commonly used by Redis data store?

• A. 27017 TCP
• B. 1883 TCP
• C. 445 TCP
• D. 6379 TCP

Answer: (D)

Redis is accessed over TCP, and by default it listens on port 6379. That means clients connect to the server using TCP to port 6379, which is why this pairing is the standard match for Redis. The other ports point to different services—27017 is commonly used by MongoDB, 1883 by MQTT, and 445 by SMB—so they aren’t the typical Redis combination. In practice, Redis runs its traffic over TCP on that default port, with the data format carried over the TCP connection using Redis’ own RESP, but the essential match here is the default port 6379 on TCP.