> For the complete documentation index, see [llms.txt](https://docs.enlyze.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enlyze.com/en/connect/ot-connectivity/supported-industrial-protocols/fins/known-issues.md).

# Tips & practical notes

This page collects tips and practical notes for operating the FINS connector with Omron controllers via the [FINS protocol](/en/connect/ot-connectivity/supported-industrial-protocols/fins.md).

## Find a controller with an unknown address

### Situation

Sometimes neither the IP address nor the FINS node of a controller is documented. Without these values, you cannot create a data source.

### Approach

FINS over Ethernet accepts connections on TCP port `9600`. Instead of guessing addresses, scan the machine network from a computer with access to that network using a port scanner, looking specifically for devices with port `9600` open:

* Scan the relevant subnet with a port scanner. Suitable tools include [Nmap](https://nmap.org/) (e.g. `nmap -p 9600 --open 192.168.0.0/24`), [masscan](https://github.com/robertdavidgraham/masscan) for large address ranges, or [Angry IP Scanner](https://angryip.org/) with a graphical interface.
* Each hit is a candidate for a FINS-capable controller. From the discovered IP address you can then derive the FINS address.

{% hint style="info" %}
Narrow the scan range as much as possible beforehand and scan the known subnet specifically (e.g. a `/24` range). Blindly scanning the entire address space is possible but takes a very long time.
{% endhint %}

### Derive the address

Once the IP address is known, derive the FINS address as follows:

* **Node**: often the last octet of the IP address (e.g. IP `192.168.0.220` → node `220`).
* **Network**: usually `0`.
* **Unit**: `0` for the CPU.

For a full example, see [Local and remote address](/en/connect/ot-connectivity/supported-industrial-protocols/fins.md#local-and-remote-address).

## No connection despite a correct IP

If the controller does not respond even though the IP address is reachable, check the following:

* **Network address**: in most setups `0` is correct. In rare cases, for example when additional modules are occupied on the rack, `1` is required. Try both values.
* **Unique local address**: the FINS address of the Edge Device must be unique on the network and must not collide with the node of the controller or other devices.
* **IP-to-node table**: for controllers with a fixed IP-to-node mapping, the Edge Device node must be entered in the controller configuration for communication to succeed.

If you have any questions, feel free to contact us at <support@enlyze.com>.