# Not able to connect to Ignition OPC server from another application

**URL:** <https://forum.inductiveautomation.com/t/not-able-to-connect-to-ignition-opc-server-from-another-application/113212>\
**Category:** Ignition\
**Tags:** ignition81\
**Created:** [January 12, 2026, 2:31pm UTC](https://forum.inductiveautomation.com/t/not-able-to-connect-to-ignition-opc-server-from-another-application/113212 "2026-01-12T14:31:08Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Nageshwar\_Nagula](https://avatars.discourse-cdn.com/v4/letter/n/e9c0ed/32.png) [@Nageshwar\_Nagula](https://forum.inductiveautomation.com/u/Nageshwar_Nagula)\
**Post date:** [January 12, 2026, 2:31pm UTC](https://forum.inductiveautomation.com/t/not-able-to-connect-to-ignition-opc-server-from-another-application/113212/1 "2026-01-12T14:31:08Z")

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I am trying to connect ignition opc server in 3rd party application, it is giving internal server error and getting time out.

```python

OPC_UA_ENDPOINT = "opc.tcp://:62541"
async def get_client():
client = Client(url=OPC_UA_ENDPOINT )
client.set_user("opcuauser")
client.set_password("password")
client.set_security_string(
"Basic256Sha256,SignAndEncrypt,client_cert.pem,client_key.pem"
)

client = await get_client()
try:
node = client.get_node(node_id)
value = await node.read_value()
return {"node_id": node_id, "value": value}
except Exception as e:
raise HTTPException(status_code=500, detail=str(e))
finally:
await client.disconnect()

```

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<div class="post-metadata">

**Author:** ![tgarrison](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/tgarrison/32/80965_2.png) [@tgarrison](https://forum.inductiveautomation.com/u/tgarrison)\
**Post date:** [January 12, 2026, 3:44pm UTC](https://forum.inductiveautomation.com/t/not-able-to-connect-to-ignition-opc-server-from-another-application/113212/2 "2026-01-12T15:44:13Z")

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By default the OPC-UA server only allows connections from the localhost I believe. And no anonymous connections. Check and adjust settings as needed to suit your situation.

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**Author:** ![michael.flagler](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/michael.flagler/32/26272_2.png) [@michael.flagler](https://forum.inductiveautomation.com/u/michael.flagler)\
**Post date:** [January 12, 2026, 3:57pm UTC](https://forum.inductiveautomation.com/t/not-able-to-connect-to-ignition-opc-server-from-another-application/113212/3 "2026-01-12T15:57:14Z")

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Your OPC-UA endpoint doesn't look like a valid URL to me. Shouldn't it be `opc.tcp://127.0.0.1:62541` (missing the IP), or does it just assume it's localhost if no IP is provided? Personally I don't like to leave things like this to assumption and think it should be explicitly called out.

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<div class="post-metadata">

**Author:** ![Nageshwar\_Nagula](https://avatars.discourse-cdn.com/v4/letter/n/e9c0ed/32.png) [@Nageshwar\_Nagula](https://forum.inductiveautomation.com/u/Nageshwar_Nagula)\
**Post date:** [January 13, 2026, 5:15am UTC](https://forum.inductiveautomation.com/t/not-able-to-connect-to-ignition-opc-server-from-another-application/113212/4 "2026-01-13T05:15:31Z")

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> [@Nageshwar\_Nagula](#):
>
> `"opc.tcp://:62541"`

not mentioned the ip address for security reasons