Why cannot an asynchronous client stay alive for a long time after being disconnected？

[DR5DWLliangyu]

Once I had successfully established a connection using the synchronous client and proceeded with the normal publishing and subscribing work, I disconnected the network cable from the broker. A week later, when I plugged back in and called reconnect (), I was still able to connect to the broker。
But when I do the same with an asynchronous client, I always end up with a connection failure error.

[fpagliughi]

Weird. The Synchronous client is just a very thin layer around the asynchronous client. So really they’re the same as far as the communication layer goes.

[DR5DWLliangyu]

This is the message that failed to be reconnected using an asynchronous client