Ok my first bug report, i have chatgtp rewrite my text, since well my spelling and grammer is not so good.

Steps to Reproduce:

1. Initial Setup:

• • Create a new host.
  • Ensure the Zabbix agent is installed on the target host and configured for active checks, reporting to the Zabbix server.
  • The target host should have a network service (e.g., SSH on port 22, or FTP on port 21 in essence it should be down) configured in such a way that it will not be reachable on its default Zabbix agent interface (e.g., agent interface is IPv6, but the service only listens on IPv4, or the service is stopped).

1. Link Minimal Working Active Template:

• • Link a minimal standard template designed for active agent monitoring, such as the "Zabbix agent active" template (which typically includes items like zabbix[host,active_agent,available], agent.ping (active), agent.hostname, agent.version).
  • Observation: At this point, after data collection starts, the ZBX agent availability icon for the host should turn green, indicating the agent is available. The zabbix[host,active_agent,available] item should report 1 (available), and agent.ping (active) should report 1 (Up).

1. Add Failing Simple Check Item:

• • Edit the same minimal "Zabbix agent active" template (or a copy of it).
  • Add a new item with the following characteristics:
    • Type: Simple check
    • Key: net.tcp.service[<service>,,<port>] (e.g., net.tcp.service[ssh,,22] or net.tcp.service[ftp,,21]). The <service> can be any service string like ssh, ftp, tcp, etc. The empty <ip> field ensures it uses the host's default agent interface. The <port> should correspond to the service.
    • Ensure this check will fail based on the setup in step 1 (i.e., the service is not reachable on the default agent interface at that port).
    • Ensure this new item is enabled.

1. Observe Behavior Change:

• • Wait for Zabbix to update item statuses and host availability. A hard refresh of the Zabbix UI may be necessary.

Observed Behavior: After adding the enabled (and failing) net.tcp.service[<service>,,<port>] Simple Check item, the ZBX agent availability icon for the host turns gray (or fails to remain/turn green). This happens despite:

• The zabbix[host,active_agent,available] internal item still reporting 1 (available) in "Latest data".
• The agent.ping (active) item still reporting 1 (Up) in "Latest data".

Disabling just the failing net.tcp.service item in the template immediately causes the ZBX agent availability icon to turn green again (assuming the agent is indeed available).

This behavior has been observed by the me on at least two different Zabbix installations and is reproducible with different services (e.g., ssh, ftp) in the net.tcp.service item key.

Expected Behavior: The ZBX agent availability icon should reflect the actual availability status of the Zabbix agent communication, primarily determined by agent-specific mechanisms like the zabbix[host,active_agent,available] internal item and/or successful active agent.ping checks. The status of an unrelated "Simple Check" item (which is performed by the Zabbix Server/Proxy, not the agent) should not directly override or cause the ZBX agent availability icon to show as gray/unknown if the agent itself is confirmed to be available. Each availability icon (ZBX, SNMP, JMX, IPMI) should reflect its respective channel.

Additional Information (Optional):

• The issue appears to be tied to the enabled and failing state of the net.tcp.service Simple Check item. If the Simple Check item is configured to target a service that is responsive (and thus the item reports 1), the ZBX icon appears to remain green but i should test this some more.