# Writing to OPC-UA server memory JSON tag from OPC-UA Client

**URL:** <https://forum.inductiveautomation.com/t/writing-to-opc-ua-server-memory-json-tag-from-opc-ua-client/55950>\
**Category:** Ignition\
**Created:** [February 9, 2022, 8:43pm UTC](https://forum.inductiveautomation.com/t/writing-to-opc-ua-server-memory-json-tag-from-opc-ua-client/55950 "2022-02-09T20:43:58Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![edward.fowler](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/edward.fowler/32/24179_2.png) [@edward.fowler](https://forum.inductiveautomation.com/u/edward.fowler)\
**Post date:** [February 9, 2022, 8:43pm UTC](https://forum.inductiveautomation.com/t/writing-to-opc-ua-server-memory-json-tag-from-opc-ua-client/55950/1 "2022-02-09T20:43:58Z")

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I’ve successfully exposed my gateways tags to and external OPC-UA client. I can read everything. I can write values to memory Integer and String tags from the client. However, I can’t write to a memory JSON tag from the client. When I try writing the client gives me an error, `The access level does not allow writing to the node.` There is nothing different about my three test tags, just the data type.

Does Ignition not allow writing to a JSON tag from an OPC client or do I have to set up some kind of special permission or rule? Why would writing to a JSON tag be different to writing to an Integer or String.

Many thanks!  
Regards,  
Ted.

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**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, 2022, 9:28pm UTC](https://forum.inductiveautomation.com/t/writing-to-opc-ua-server-memory-json-tag-from-opc-ua-client/55950/2 "2022-02-09T21:28:14Z")

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It doesn’t look like it is supported right now.

There is no Document (JSON) OPC UA datatype, so we expose it as a Node with a String DataType. When an OPC UA client writes a String back it doesn’t appear that the exposed tags feature or Ignition’s tag system has any brains to try to turn String back into Document, so I think that’s why it fails.

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**Author:** ![edward.fowler](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/edward.fowler/32/24179_2.png) [@edward.fowler](https://forum.inductiveautomation.com/u/edward.fowler)\
**Post date:** [February 9, 2022, 9:36pm UTC](https://forum.inductiveautomation.com/t/writing-to-opc-ua-server-memory-json-tag-from-opc-ua-client/55950/3 "2022-02-09T21:36:13Z")

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Hi Kevin,  
Thanks for fast response!  
It’d be a nice feature in future releases 🙂  
Thanks again!  
Regards,  
Ted.