Error message
In the morning, my colleague in the data group told me that there were several programs reporting errors. After checking the log, the error message was found:

paramiko.ssh_exception.SSHException: Error reading SSH protocol banner

After a search, it was revealed that the error was caused by the banner_TIMEOUT default setting being too short, only 15s.
Error analysis
See the transport code under Paramiko library. Py:

class Transport(threading.Thread, ClosingContextManager):
        self.banner_timeout = 15
        # how long (seconds) to wait for the handshake to finish after SSH

Reset the banner_TIMEOUT property value
Most of the methods on the Internet is to modify the source code, reinstall, feel a little trouble. I’m going to reset the properties in the code.

transport = paramiko.Transport((self.host, self.port))
print(transport.banner_timeout)
transport.banner_timeout = 30
print(transport.banner_timeout)

After testing, the two printed property values are different, indicating that the property is set successfully and the problem is solved.

Reproduced in: https://www.cnblogs.com/everfight/p/paramiko_ssh_exception.html