# Gateway Connection Error **URL:** \ **Category:** Ignition\ **Created:** [November 10, 2025, 11:08am UTC](https://forum.inductiveautomation.com/t/gateway-connection-error/112067 "2025-11-10T11:08:23Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Senthee\_Wu](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/senthee_wu/32/67770_2.png) [@Senthee\_Wu](https://forum.inductiveautomation.com/u/Senthee_Wu)\ **Post date:** [November 10, 2025, 11:08am UTC](https://forum.inductiveautomation.com/t/gateway-connection-error/112067/1 "2025-11-10T11:08:23Z")
Hello everyone, I encountered the following error while configuring a gateway connection. Both virtual machines are running on the same physical host, so theoretically, traffic between them shouldn't pass through a firewall. This is the first time I've run into this issue—what should I do next? ```python Connection attempt to 'ws://10.145.1.103:8060/system/ws-control-servlet?name=ignition-5eebd5a8229f-master&uuid=2b058902-0e5f-40e1-9f4d-d811b7301602&serializer=protobuf&url=http://10.145.1.104:8088/system' failed! Response code='400', error message='org.eclipse.jetty.websocket.api.exceptions.UpgradeException: org.eclipse.jetty.websocket.core.exception.UpgradeException: 400 Illegal character CNTL=0x15'. ``` ---
**Author:** ![JVDM](https://avatars.discourse-cdn.com/v4/letter/j/ac8455/32.png) [@JVDM](https://forum.inductiveautomation.com/u/JVDM)\ **Post date:** [November 10, 2025, 11:17am UTC](https://forum.inductiveautomation.com/t/gateway-connection-error/112067/2 "2025-11-10T11:17:34Z")
`400 Illegal character CNTL=0x15` The ASCII character 0x15 is for NAK. 10.145.1.103 and 10.145.1.104 are trying to set up a connection. 103 rejects the connection from 104, probably because there’s something wrong with the connection information. Please check whether the connection information is written correctly and doesn’t contain any whitespaces. It could be in any field, so be thorough. ---
**Author:** ![Senthee\_Wu](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/senthee_wu/32/67770_2.png) [@Senthee\_Wu](https://forum.inductiveautomation.com/u/Senthee_Wu)\ **Post date:** [November 10, 2025, 11:23am UTC](https://forum.inductiveautomation.com/t/gateway-connection-error/112067/3 "2025-11-10T11:23:22Z")
I checked and didn't find any spaces. ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/9/790351f55b036bc7220bc8b9d62bda08646af1a1.png) ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/5/d/5d22d6687126de1b0211ef49f9f03b1aaf91d270.png) ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/b/4/b44430fa3aafff55a8607a43f917ee0cac88bfe6.png) ---
**Author:** ![JVDM](https://avatars.discourse-cdn.com/v4/letter/j/ac8455/32.png) [@JVDM](https://forum.inductiveautomation.com/u/JVDM)\ **Post date:** [November 10, 2025, 11:30am UTC](https://forum.inductiveautomation.com/t/gateway-connection-error/112067/4 "2025-11-10T11:30:11Z")
```python Connection attempt to ' ws://10.145.1.103:8060/system/ws-control-servlet? name=ignition-5eebd5a8229f-master& uuid=2b058902-0e5f-40e1-9f4d-d811b7301602& serializer=protobuf& url=http://10.145.1.104:8088/system' failed! Response code='400', error message='org.eclipse.jetty.websocket.api.exceptions.UpgradeException: org.eclipse.jetty.websocket.core.exception.UpgradeException: 400 Illegal character CNTL=0x15'. ``` It doesn’t necessarily have to be spaces, it could be a typo as well in any of these values: - receiving IP address / port - Transmitting IP address / port - UUID - Gateway name - IP address settings on the machines themselves ---
**Author:** ![mgross](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/mgross/32/3311_2.png) [@mgross](https://forum.inductiveautomation.com/u/mgross)\ **Post date:** [November 10, 2025, 2:06pm UTC](https://forum.inductiveautomation.com/t/gateway-connection-error/112067/5 "2025-11-10T14:06:21Z")
Port 8060 can only be used for gateway network SSL connections. You have to check the “Use SSL” checkbox in your connection settings.