# Parameters

### General <a href="#h.iy2j3qpghg0m" id="h.iy2j3qpghg0m"></a>

* **Host:** contains target IP address or database server hostname.&#x20;
* **Port:** contains database server port (8086 by default).&#x20;
* **Database:** contains name of the database.&#x20;
* **Retention Policy:** contains retention policy.&#x20;

{% hint style="info" %}
Note that if retention policy doesn’t exist in the database server, writing will not be performed
{% endhint %}

* **Measurement:** contains measurement name.
* **Request Timeout:** contains time interval (in milliseconds) within which the response from the database server must be received. If the response is not received during the specified interval an error occurs.
* **Wait after Write:** contains timeout interval (in milliseconds) before the start of next data writing to the store.
* **Wait after Error**: contains timeout interval (in milliseconds) in case an error occurs during data writing or store preparation.
* **Inter-request Interval:** contains timeout interval (in milliseconds) before sending the next request. It is used if data doesn’t fit in one request.

### Security <a href="#h.mxh7apafhfs0" id="h.mxh7apafhfs0"></a>

* **Use Credentials:** specifies that it is necessary to use credentials (Base64 Auth in HTTP-header).
* **Username:** contains username.
* **Password:** contains password.
* **Use SSL:** specifies that it is necessary to verify database server SSL certificate.
* **SSL Verification:** contains verification mode of database server SSL certificate:
  * Accept any.
  * Verify chain of trust by using a store of certificates of the operating system.
  * Verify chain of trust by using custom certificate of certification authority.
* **Custom CA File:**  contains custom certificate of certification authority.

### Performance <a href="#h.32r40uqgjetb" id="h.32r40uqgjetb"></a>

* **Series per Request:** contains maximum number of time series that can be written per one request.
* **Samples per Request:** contains maximum number of samples for each time series that can be written per one request.
* **Max. Buffer Size:** contains maximum size of sample buffer for each time series that is accumulated in the server memory.

### Advanced <a href="#h.33nk75zg8yc1" id="h.33nk75zg8yc1"></a>

* **Add Server UID to Tag:** specifies that for all store associated time series server UID will be added as *su* tag value (record metadata).
* **Add Store UID to Tag:** specifies that for all store associated time series store UID will be added as *stu* tag value (record metadata).
* **Add Time Series UID to Tag:** specifies that for all store associated time series time series UID will be added as *tsu* tag value (record metadata).
* **Add Time Series Path to Tag:** specifies that for all store associated time series string path to time series will be added as *tsp* tag value (record metadata).
* **Add Time Series Comment to Tag**: specifies that for all store associated time series comment to time series will be added as *tsc* tag value (record metadata).
* **Use Server UID in ‘Hash’ Addresses:** specifies that unique server identifier should be used to generate *Hash* addresses.

Most of the parameters described above are available as OPC UA items. More information about editing server object properties via OPC UA is described [<mark style="color:blue;">here</mark>](https://docs.monokot.io/basics/opc-ua/access-to-object-settings).