# OPC UA Client Failover

**URL:** <https://forum.inductiveautomation.com/t/opc-ua-client-failover/43177>\
**Category:** Ignition\
**Created:** [February 9, 2021, 2:25pm UTC](https://forum.inductiveautomation.com/t/opc-ua-client-failover/43177 "2021-02-09T14:25:03Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![mohamad.tayara](https://avatars.discourse-cdn.com/v4/letter/m/977dab/32.png) [@mohamad.tayara](https://forum.inductiveautomation.com/u/mohamad.tayara)\
**Post date:** [February 9, 2021, 2:25pm UTC](https://forum.inductiveautomation.com/t/opc-ua-client-failover/43177/1 "2021-02-09T14:25:03Z")

</div>

What are the conditions for Ignition`s OPC client to switch to Failover OPC UA server: OPC Server Fault Only? and does it support OPC UA Server Redundancy Standard i.e, Does the ignition verify the Service Level system variable to determine the state of the OPC server?  
Thanks

---

<div class="post-metadata">

**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:** [February 9, 2021, 2:27pm UTC](https://forum.inductiveautomation.com/t/opc-ua-client-failover/43177/2 "2021-02-09T14:27:17Z")

</div>

It checks the connection state every 5 seconds and if the number of times it checked and found it wasn't connected exceeds the configured failover threshold it switches to the other server.

> [@mohamad.tayara](#):
>
> and does it support OPC UA Server Redundancy Standard i.e, Does the ignition verify the Service Level system variable to determine the state of the OPC server?

No, neither Ignition's OPC UA client nor server know anything about OPC UA redundancy.