|Re: [mosquitto-dev] MQTT client id length|
It is 65535 bytes. This is the same as the limit in mqtt v3.1.1.
According to MQTT V3.1 Protocol Specification, "The Client Identifier (Client ID) is between 1 and 23 characters long, and uniquely identifies the client to the server. It must be unique across all clients connecting to a single server, and is the key in handling Message IDs messages with QoS levels 1 and 2. If the Client ID contains more than 23 characters, the server responds to the CONNECT message with a CONNACK return code 2: Identifier Rejected."
But I have noticed that Mosquitto is OK with client identifiers longer than 23 characters. What is mosquitto's maximum client id length?
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