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		<title>Sean Behan — test</title>
		<link>https://seanbehan.ca/posts/tag/test</link>
		<description>Posts tagged “test”.</description>
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		<managingEditor>sean@seanbehan.ca (Sean Behan)</managingEditor>
		<webMaster>sean@seanbehan.ca (Sean Behan)</webMaster>
		<lastBuildDate>Sun, 30 Aug 2026 05:35:13 GMT</lastBuildDate>
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		<guid isPermaLink="true">https://seanbehan.ca/posts/usb-cable-testing</guid>
		<title><![CDATA[USB Cable Testing on Linux]]></title>
		<description><![CDATA[usbmon turns Wireshark into a cable tester, and finds retransmissions on cables that supposedly work.]]></description>
		<link>https://seanbehan.ca/posts/usb-cable-testing</link>
		<pubDate>Wed, 15 Apr 2026 07:11:06 GMT</pubDate>
		<category>linux</category><category>test</category><category>usb</category><category>wireshark</category>
		<content:encoded><![CDATA[<p>I was interested in testing my USB cables that I know work, but wanted to see if they had any retransmission going on.</p><p>Then today, I found out Linux has a kernel module that allows you to &quot;monitor&quot; usb interfaces. Like... using wireshark.</p><p>I won&#x27;t explain how to set up wireshark for your distro, that&#x27;s for you to figure out.</p><p>Once you have wireshark set up, you just <code>sudo modprobe usbmon</code> then <code>lsusb</code>.</p><p>Find the USB interface you want to monitor in the list, then select it when starting wireshark (gui).</p><p>That&#x27;s about it... you can filter like this:</p><pre class="shiki shiki-themes github-light github-dark" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e" tabindex="0"><code><span class="line"><span>usb.urb_status != 0 &#x26;&#x26; !(usb.urb_status == -115)</span></span></code></pre><p>Short post, but hope this helps you test your own USB cables for any errors that aren&#x27;t shown in dmesg, like failed packets.</p>]]></content:encoded>
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