If the connection from the host is denied by parameter 'Server' in zabbix_agentd.conf then the following error message is displayed:
Received empty response from Zabbix Agent at [127.0.0.1]. Assuming that agent dropped connection because of access permissions.

But in case of zabbix_agent2 the error message is inconsistent:
Get value from agent failed: ZBX_TCP_READ() failed: [104] Connection reset by peer

Probable reason for that difference is:

• zabbix_agent close connection by calling shutdown() and close() on socket, results in FIN+RST packets on TCP level
• zabbix_agent2 close connection by calling net.TCPConn.Close(), results in RST packet only

Steps to reproduce:

Set
Server=zabbix.example.com
in the configuration file of agent2 (zabbix_agent2.conf)

Result:
See screenshot zabbix_agent2.png
Expected:
See screenshot zabbix_agentd.png