# USRP1: Error: Connection refused

**URL:** <https://www.ruby-forum.com/t/usrp1-error-connection-refused/230636>\
**Category:** GNU Radio\
**Created:** [June 27, 2014, 4:48am UTC](https://www.ruby-forum.com/t/usrp1-error-connection-refused/230636 "2014-06-27T04:48:17Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jason\_sam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/7993a0/32.png) [@jason\_sam](https://www.ruby-forum.com/u/jason_sam)\
**Post date:** [June 27, 2014, 4:48am UTC](https://www.ruby-forum.com/t/usrp1-error-connection-refused/230636/1 "2014-06-27T04:48:17Z")

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Dear all,

I’ve reinstalled gnuradio 3.7.0 and UHD 003.007.001. Now I got this  
error  
when connecting USRP to my PC and running some commands:

1. sudo uhd\_usrp\_probe  
Error:  
linux; GNU C++ version 4.6.3; Boost\_104601; UHD\_003.007.001-release

Error: Connection refused

1. sudo uhd\_find\_devices  
Error:  
linux; GNU C++ version 4.6.3; Boost\_104601; UHD\_003.007.001-release

## UHD Error: Device discovery error: Connection refused

## – UHD Device 0

Device Address:  
type: usrp1  
name:  
serial: 50a45bfc

How could I fix this?

Many Thanks,  
Hoang

---

<div class="post-metadata">

**Author:** ![Hoang\_Ngo\_K](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/97f17d/32.png) [@Hoang\_Ngo\_K](https://www.ruby-forum.com/u/Hoang_Ngo_K)\
**Post date:** [June 27, 2014, 11:24am UTC](https://www.ruby-forum.com/t/usrp1-error-connection-refused/230636/2 "2014-06-27T11:24:55Z")

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The ‘connection refused’ error is probably due to your firewall  
configuration blocking network broadcast probes which are sent for  
detection of ethernet connected USRPs. Try the following to force it to  
connect to the USRP1 type:

uhd\_usrp\_probe --args=“type=usrp1”

Mike

–  
Mike J. M0MIK BSc MIET  
Ettus R. Technical Support  
Email: removed\_email\_address@domain.invalid  
Web: [http://ettus.com](http://ettus.com)

On Fri, Jun 27, 2014 at 3:46 AM, Hoang Ngo K.  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)