# Use OPC-UA to connect to factory DCS as a MODBUS server **URL:** \ **Category:** General Discussion\ **Created:** [July 15, 2015, 11:13pm UTC](https://forum.inductiveautomation.com/t/use-opc-ua-to-connect-to-factory-dcs-as-a-modbus-server/10230 "2015-07-15T23:13:58Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![steven.elam](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/steven.elam/32/4797_2.png) [@steven.elam](https://forum.inductiveautomation.com/u/steven.elam)\ **Post date:** [July 15, 2015, 11:13pm UTC](https://forum.inductiveautomation.com/t/use-opc-ua-to-connect-to-factory-dcs-as-a-modbus-server/10230/1 "2015-07-15T23:13:58Z")
We are developing an Ignition project that controls a piece of equipment and needs to connect to the factory’s DCS system as a MODBUS server (aka slave). We are trying to use OPC-UA, but as I understand it, it always wants to be the client (aka master). Am I wrong about this, and if so (hopefully), how do we configure OPC-UA to act as a server? ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [July 15, 2015, 11:57pm UTC](https://forum.inductiveautomation.com/t/use-opc-ua-to-connect-to-factory-dcs-as-a-modbus-server/10230/2 "2015-07-15T23:57:58Z")
There is no module or capability in Ignition that allows it to act as a Modbus slave. ---
**Author:** ![diat150](https://avatars.discourse-cdn.com/v4/letter/d/a587f6/32.png) [@diat150](https://forum.inductiveautomation.com/u/diat150)\ **Post date:** [July 16, 2015, 2:39am UTC](https://forum.inductiveautomation.com/t/use-opc-ua-to-connect-to-factory-dcs-as-a-modbus-server/10230/3 "2015-07-16T02:39:23Z")
you may be able to use kepware or matrikon modbus opc drivers setup as modbus slaves to solve your issue.