<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage]]></title><description><![CDATA[<p dir="auto">Please be aware (I know it's obvious) but I was using chatgtp to help me sort this, I figured it would be the best way to summarize my issues:</p>
<p dir="auto">Version	8.2.1 ()<br />
Build number	release/yangtze/master/58</p>
<hr />
<h2><strong>Issue Overview</strong></h2>
<p dir="auto">I am experiencing issues with starting <strong>any VMs</strong> on my <strong>XenServer host (EXAMPLESERVER)</strong> after a power outage. No VMs on this host are working.</p>
<p dir="auto">I am using <strong>Xen Orchestra (XO Community Edition)</strong>, which is running on a <strong>separate machine</strong>. The <strong>EXAMPLESERVER host is visible in Xen Orchestra</strong>, but all VM start operations <strong>fail</strong> with the following errors:</p>
<ul>
<li><strong>HeadersTimeoutError</strong> in Xen Orchestra</li>
<li><strong>Hotplug.Device_timeout(_)</strong> when starting via <code>xe vm-start</code></li>
<li>VMs have <strong>blocked operations</strong>, preventing shutdown or reboot</li>
<li>Possible <strong>storage issues</strong> related to the VM’s virtual disks (VDIs)</li>
</ul>
<h2><strong>Error Messages &amp; Logs</strong></h2>
<h3><strong>1. VM Start Error in Xen Orchestra (XO)</strong></h3>
<pre><code>vm.start  
{  
  "id": "EXAMPLE-VM-ID",  
  "bypassMacAddressesCheck": false,  
  "force": false  
}  
{  
  "name": "HeadersTimeoutError",  
  "code": "UND_ERR_HEADERS_TIMEOUT",  
  "message": "Headers Timeout Error",  
  "call": {  
    "duration": 300642,  
    "method": "VM.start",  
    "params": [  
      "* session id *",  
      "OpaqueRef:EXAMPLE-OPAQUE-REF",  
      false,  
      false  
    ]  
  },  
  "stack": "HeadersTimeoutError: Headers Timeout Error  
    at FastTimer.onParserTimeout [as _onTimeout] (/opt/xo/xo-builds/.../dispatcher/client-h1.js:642:28)  
    at Timeout.onTick [as _onTimeout] (/opt/xo/xo-builds/.../util/timers.js:162:13)  
    at listOnTimeout (node:internal/timers:569:17)  
    at processTimers (node:internal/timers:512:7)"  
}  
</code></pre>
<h3><strong>2. CLI Error - Hotplug Device Timeout</strong></h3>
<pre><code>[22:22 EXAMPLESERVER ~]# xe vm-start uuid=EXAMPLE-VM-UUID  
The server failed to handle your request, due to an internal error.  
message: xenopsd internal error: Hotplug.Device_timeout(_)  
</code></pre>
<h3><strong>3. VMs are Blocked from Shutdown or Restart</strong></h3>
<pre><code>[22:59 EXAMPLESERVER ~]# xe vm-shutdown uuid=EXAMPLE-VM-UUID force=true  
You attempted an operation that was explicitly blocked (see the blocked_operations field of the given object).  
ref: EXAMPLE-VM-UUID  
code: true  
</code></pre>
<h3><strong>4. VM Parameters Show It is in a Blocked State</strong></h3>
<pre><code>xe vm-param-list uuid=EXAMPLE-VM-UUID params=blocked-operations  
blocked-operations (MRW): clean_reboot: true; hard_reboot: true; pause: true;  
shutdown: true; clean_shutdown: true; hard_shutdown: true; destroy: true  
</code></pre>
<h3><strong>5. Storage Issues Detected - LVM Shows Active VHDs but Possible Issues</strong></h3>
<pre><code>pvscan  
  PV /dev/sdc    VG VG_XenStorage-EXAMPLE   lvm2 [&lt;1.82 TiB / &lt;161.53 GiB free]  
  PV /dev/sdb3   VG VG_XenStorage-EXAMPLE   lvm2 [182.06 GiB / 141.96 GiB free]  
  PV /dev/sda    VG VG_XenStorage-EXAMPLE   lvm2 [1.09 TiB / &lt;575.00 GiB free]  
</code></pre>
<hr />
<h2><strong>Troubleshooting Steps Tried</strong></h2>
<h3><strong>1. Restarted XenAPI and XenOpsD</strong></h3>
<pre><code>systemctl restart xapi  
systemctl restart xenopsd-xc  
</code></pre>
<ul>
<li><strong>Result:</strong> No improvement, VMs still do not start.</li>
</ul>
<h3><strong>2. Attempted to Unpause the VM</strong></h3>
<pre><code>xe vm-unpause uuid=EXAMPLE-VM-UUID  
</code></pre>
<ul>
<li><strong>Result:</strong> <code>xe</code> command hangs indefinitely.</li>
</ul>
<h3><strong>3. Checked for Blocked Operations</strong></h3>
<pre><code>xe vm-param-list uuid=EXAMPLE-VM-UUID params=blocked-operations  
</code></pre>
<ul>
<li><strong>Result:</strong> Shows that shutdown, reboot, and destroy operations are all blocked.</li>
</ul>
<h3><strong>4. Reset VM Power State</strong></h3>
<pre><code>xe vm-reset-powerstate uuid=EXAMPLE-VM-UUID force=true  
</code></pre>
<ul>
<li><strong>Result:</strong> No change, VM remains in a paused state.</li>
</ul>
<h3><strong>5. Checked VDI Attachments</strong></h3>
<pre><code>xe vbd-list vm-uuid=EXAMPLE-VM-UUID  
</code></pre>
<ul>
<li><strong>Result:</strong> Disks appear attached but VMs still do not start.</li>
</ul>
<h3><strong>6. Restarted Xen Orchestra</strong></h3>
<pre><code>systemctl restart xo-server  
systemctl restart xo-web  
</code></pre>
<ul>
<li><strong>Result:</strong> No change.</li>
</ul>
<h3><strong>7. Scanned Storage Repositories</strong></h3>
<pre><code>xe sr-list  
xe sr-scan uuid=EXAMPLE-SR-UUID  
</code></pre>
<ul>
<li><strong>Result:</strong> Storage seems intact, but VMs still do not boot.</li>
</ul>
<hr />
<h2><strong>Additional Notes</strong></h2>
<p dir="auto"><img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/2705.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--white_check_mark" style="height:23px;width:auto;vertical-align:middle" title="✅" alt="✅" /> The <strong>host lost power</strong>, and since rebooting, <strong>no VMs on this host will start</strong>.<br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/2705.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--white_check_mark" style="height:23px;width:auto;vertical-align:middle" title="✅" alt="✅" /> <strong>Xen Orchestra is running on a separate machine</strong> and can see the host.<br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/2705.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--white_check_mark" style="height:23px;width:auto;vertical-align:middle" title="✅" alt="✅" /> Other hosts in the pool (if any) are functioning properly.<br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/2705.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--white_check_mark" style="height:23px;width:auto;vertical-align:middle" title="✅" alt="✅" /> The error <strong>Hotplug.Device_timeout(_)</strong> suggests <strong>a VDI issue</strong>, but VDIs appear attached.<br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/2705.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--white_check_mark" style="height:23px;width:auto;vertical-align:middle" title="✅" alt="✅" /> The <strong>HeadersTimeoutError</strong> in XO indicates <strong>XAPI is slow or unresponsive</strong>.<br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/2705.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--white_check_mark" style="height:23px;width:auto;vertical-align:middle" title="✅" alt="✅" /> The <strong>VM is blocked from shutdown/reboot</strong> and cannot be started via CLI or XO.</p>
<hr />
<h2><strong>Request for Help</strong></h2>
<p dir="auto"><img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/1f539.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--small_blue_diamond" style="height:23px;width:auto;vertical-align:middle" title="🔹" alt="🔹" /> <strong>What could be preventing VMs from starting?</strong><br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/1f539.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--small_blue_diamond" style="height:23px;width:auto;vertical-align:middle" title="🔹" alt="🔹" /> <strong>How can I clear the blocked operations?</strong><br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/1f539.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--small_blue_diamond" style="height:23px;width:auto;vertical-align:middle" title="🔹" alt="🔹" /> <strong>Could this be a corrupted VM state, and if so, how can I recover it?</strong><br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/1f539.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--small_blue_diamond" style="height:23px;width:auto;vertical-align:middle" title="🔹" alt="🔹" /> <strong>Is there a way to manually attach the VDIs and force a boot?</strong><br />
<img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/1f539.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--small_blue_diamond" style="height:23px;width:auto;vertical-align:middle" title="🔹" alt="🔹" /> <strong>Any ideas on why Xen Orchestra times out when starting the VM?</strong></p>
<p dir="auto">Would really appreciate any guidance on <strong>how to force the VMs to start or recover from this state</strong>.</p>
<p dir="auto">Thanks in advance! <img src="https://xcp-ng.org/forum/assets/plugins/nodebb-plugin-emoji/emoji/android/1f680.png?v=c63c1619ba5" class="not-responsive emoji emoji-android emoji--rocket" style="height:23px;width:auto;vertical-align:middle" title="🚀" alt="🚀" /></p>
<p dir="auto">I'm no expert but I haven't had any issues in a year of using xcp-ng.</p>
<p dir="auto">SPC</p>
]]></description><link>https://xcp-ng.org/forum/topic/10229/xenserver-vm-fails-to-start-headerstimeouterror-hotplug-device_timeout-_-after-power-outage</link><generator>RSS for Node</generator><lastBuildDate>Wed, 11 Mar 2026 01:40:44 GMT</lastBuildDate><atom:link href="https://xcp-ng.org/forum/topic/10229.rss" rel="self" type="application/rss+xml"/><pubDate>Wed, 08 Jan 2025 10:06:47 GMT</pubDate><ttl>60</ttl><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Mon, 13 Jan 2025 19:43:16 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/spcmediaco" aria-label="Profile: spcmediaco">@<bdi>spcmediaco</bdi></a></p>
<p dir="auto">FYI, I never figured out how to fix. I am doing backup recovery now.</p>
]]></description><link>https://xcp-ng.org/forum/post/88071</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/88071</guid><dc:creator><![CDATA[spcmediaco]]></dc:creator><pubDate>Mon, 13 Jan 2025 19:43:16 GMT</pubDate></item><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Thu, 09 Jan 2025 06:08:57 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/spcmediaco" aria-label="Profile: spcmediaco">@<bdi>spcmediaco</bdi></a></p>
<p dir="auto">I restored a backup VM to the host that is currently working and that VM worked, now I'm trying to migrate a VM from the 'broken' host to the working host and see if that works. Maybe I need to format the 'broken' host and reinstall it.</p>
]]></description><link>https://xcp-ng.org/forum/post/87914</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/87914</guid><dc:creator><![CDATA[spcmediaco]]></dc:creator><pubDate>Thu, 09 Jan 2025 06:08:57 GMT</pubDate></item><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Wed, 08 Jan 2025 19:40:48 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/danp" aria-label="Profile: Danp">@<bdi>Danp</bdi></a> said in <a href="/forum/post/87903">XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage</a>:</p>
<blockquote>
<p dir="auto">Check the VM's Advanced tab in XO and make sure these options are not enabled --</p>
</blockquote>
<p dir="auto">Thank you, I did check and they are unchecked. Still stuck, it seems like XO running on my other host is still trying to start it over and over again with bad power state or something:</p>
<p dir="auto"><img src="/forum/assets/uploads/files/1736365242635-untitled-resized.png" alt="Untitled.png" class=" img-fluid img-markdown" /></p>
]]></description><link>https://xcp-ng.org/forum/post/87905</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/87905</guid><dc:creator><![CDATA[spcmediaco]]></dc:creator><pubDate>Wed, 08 Jan 2025 19:40:48 GMT</pubDate></item><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Wed, 08 Jan 2025 19:16:48 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/spcmediaco" aria-label="Profile: spcmediaco">@<bdi>spcmediaco</bdi></a> Check the VM's Advanced tab in XO and make sure these options are not enabled --<br />
<img src="/forum/assets/uploads/files/1736363800686-0a860a8e-ddfd-41da-b5a0-e68162878360-image.png" alt="0a860a8e-ddfd-41da-b5a0-e68162878360-image.png" class=" img-fluid img-markdown" /></p>
]]></description><link>https://xcp-ng.org/forum/post/87903</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/87903</guid><dc:creator><![CDATA[Danp]]></dc:creator><pubDate>Wed, 08 Jan 2025 19:16:48 GMT</pubDate></item><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Wed, 08 Jan 2025 18:53:11 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/olivierlambert" aria-label="Profile: olivierlambert">@<bdi>olivierlambert</bdi></a> I appreciate the response, and I'm trying to do this (with the help of LLMs) however, could you point me in the direction on how to do this as I'm still having difficulties with this issue.</p>
]]></description><link>https://xcp-ng.org/forum/post/87900</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/87900</guid><dc:creator><![CDATA[spcmediaco]]></dc:creator><pubDate>Wed, 08 Jan 2025 18:53:11 GMT</pubDate></item><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Wed, 08 Jan 2025 14:07:12 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/spcmediaco" aria-label="Profile: spcmediaco">@<bdi>spcmediaco</bdi></a> Great first post.</p>
<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/forum/user/olivierlambert" aria-label="Profile: olivierlambert">@<bdi>olivierlambert</bdi></a> Great support!</p>
]]></description><link>https://xcp-ng.org/forum/post/87875</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/87875</guid><dc:creator><![CDATA[DustinB]]></dc:creator><pubDate>Wed, 08 Jan 2025 14:07:12 GMT</pubDate></item><item><title><![CDATA[Reply to XenServer VM Fails to Start - HeadersTimeoutError &amp; Hotplug.Device_timeout(_) After Power Outage on Wed, 08 Jan 2025 10:11:36 GMT]]></title><description><![CDATA[<p dir="auto">You need to remove the blocked operations.</p>
]]></description><link>https://xcp-ng.org/forum/post/87847</link><guid isPermaLink="true">https://xcp-ng.org/forum/post/87847</guid><dc:creator><![CDATA[olivierlambert]]></dc:creator><pubDate>Wed, 08 Jan 2025 10:11:36 GMT</pubDate></item></channel></rss>