# "error":"backend URL (//:8081/system\_handler) must have ws:// or wss://

**URL:** <https://discourse.sensu.io/t/error-backend-url-8081-system-handler-must-have-ws-or-wss/1914>\
**Category:** Sensu Go\
**Created:** [June 24, 2020, 5:33am UTC](https://discourse.sensu.io/t/error-backend-url-8081-system-handler-must-have-ws-or-wss/1914 "2020-06-24T05:33:46Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![masifpak](https://avatars.discourse-cdn.com/v4/letter/m/b38774/32.png) [@masifpak](https://discourse.sensu.io/u/masifpak)\
**Post date:** [June 24, 2020, 5:33am UTC](https://discourse.sensu.io/t/error-backend-url-8081-system-handler-must-have-ws-or-wss/1914/1 "2020-06-24T05:33:46Z")

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Hi Geeks,

I have installed sensu-aggent 5.21 on centos6.5 but my server is on centos7. When I start sensu-agent I prompt the followingg error. Any clue to fix the isssue.

> “component”:“agent”,“level”:“info”,“msg”:“compacting api queue”,“time”:“2020-06-24T05:29:12Z”}  
> {“component”:“agent”,“level”:“info”,“msg”:“finished api queue compaction”,“time”:“2020-06-24T05:29:12Z”}  
> {“component”:“agent”,“level”:“info”,“msg”:“using password auth”,“time”:“2020-06-24T05:29:12Z”}  
> {“component”:“agent”,“error”:“backend URL (//:8081/system\_handler) must have ws:// or wss:// scheme”,“level”:“fatal”,“msg”:“error executing sensu-agent”,“time”:“2020-06-24T05:29:12Z”}

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<div class="post-metadata">

**Author:** ![jspaleta](https://sea2.discourse-cdn.com/flex016/user_avatar/discourse.sensu.io/jspaleta/32/141_2.png) [@jspaleta](https://discourse.sensu.io/u/jspaleta)\
**Post date:** [June 24, 2020, 6:13am UTC](https://discourse.sensu.io/t/error-backend-url-8081-system-handler-must-have-ws-or-wss/1914/2 "2020-06-24T06:13:35Z")

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Hey,

That error looks to me like the `backend_url` for the agent configuration is misconfigured.  
You should probably check the /etc/sensu/agent.yml file.

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<div class="post-metadata">

**Author:** ![masifpak](https://avatars.discourse-cdn.com/v4/letter/m/b38774/32.png) [@masifpak](https://discourse.sensu.io/u/masifpak)\
**Post date:** [June 24, 2020, 6:34am UTC](https://discourse.sensu.io/t/error-backend-url-8081-system-handler-must-have-ws-or-wss/1914/3 "2020-06-24T06:34:53Z")

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Thanks for your reply.

You are very right. Mentioned line was uncommented. I commented it and strated. Work fine now. Again Thanks.

#statsd-event-handlers:  
**# - system\_handler**