202004 - Fortinet Connection Timed Out
Agent error code #202004 indicates that the agent attempted to connect to the Fortinet device but the connection timed out before a response was received. The agent waits up to 10 seconds for a response.
This error is distinct from connection failures (#202000), which cover immediate rejections or DNS resolution failures. Error #202004 specifically means the connection attempt was initiated but no response arrived within the timeout period.
Common causes include:
- A network firewall or access control list is silently dropping traffic to the management interface (no reject, just drop)
- The Fortinet device is under heavy load and unable to respond in time
- Network routing issues are causing packets to be lost between the agent and the device
- The configured hostname resolves to an IP address that is not the device's management interface
- The device's management interface is on a different port than expected
Steps to Resolve
Check Network Connectivity
- From the agent host, test connectivity to the Fortinet device's management port:
curl -v https://<hostname>:<port>(or usetelnet <hostname> <port>to test TCP connectivity)
- If the connection hangs without a response, there is likely a firewall silently dropping the traffic
- Verify that no intermediate firewalls, security groups, or network ACLs are blocking traffic between the agent and the Fortinet device
Verify the Hostname and Port
- Confirm the URL configured in Knocknoc is correct and points to the device's management interface
- The default management port for Fortinet devices is 443
- If the device uses a non-standard port, ensure the correct port is included in the URL (e.g.,
https://fw.example.com:8443)
Check Device Health
- Log into the Fortinet device from another location to confirm it is responsive
- If the device is under heavy load, check CPU and memory utilisation
- FortiManager devices may become slow under high API load — consider increasing API resource limits if applicable
Check for Asymmetric Routing
- Verify that the return path from the Fortinet device to the agent is functional
- Asymmetric routing (traffic arriving via one path but responses leaving via another) can cause timeouts if return traffic is blocked
Still Having Issues?
We can help you out, contact us at support@knocknoc.io.