<![CDATA[Error 13: Invalid or unsupported executable format]]>Greetings,

After a clean shutdown yesterday, two older CentOS 5 VM that have been running fine for many years refused to come back up. I'm running XCP 7.6.

The VM CPU spikes to 100%, and I get "Error 13: Invalid or unsupported executable format" in the console.

I can't seem to restore from a recent (3 day old) snapshot either, same problem.

After doing some searching and trying launching from Grub, I'm stuck.

Can anyone shed some light on this?

Thanks for your insight.

]]>https://xcp-ng.org/forum/topic/6169/error-13-invalid-or-unsupported-executable-formatRSS for NodeMon, 12 Oct 2026 11:54:54 GMTMon, 01 Aug 2022 20:34:00 GMT60<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Thu, 04 Aug 2022 16:42:44 GMT]]>Good news 🙂 Also, now you are in HVM, which is a LOT better than PV for a lot of reasons (security, performance etc.)

]]>https://xcp-ng.org/forum/post/51879https://xcp-ng.org/forum/post/51879Thu, 04 Aug 2022 16:42:44 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Thu, 04 Aug 2022 16:38:07 GMT]]>@olivierlambert,
I ended up copying the old application data from the crashed VM via a live CD and deployed a new VM (running on HVM.) Everything seems to be working fine now.

]]>https://xcp-ng.org/forum/post/51878https://xcp-ng.org/forum/post/51878Thu, 04 Aug 2022 16:38:07 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 20:12:16 GMT]]>@olivierlambert,
Thanks for the assistance. I'm exporting the data from the VM via Live CD and will build a new VM and import applications from old VM.

]]>https://xcp-ng.org/forum/post/51790https://xcp-ng.org/forum/post/51790Tue, 02 Aug 2022 20:12:16 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 18:41:04 GMT]]>First, I would start a live CD and chroot into it to see if you can get all the files (in case you can spot something corrupted)

]]>https://xcp-ng.org/forum/post/51779https://xcp-ng.org/forum/post/51779Tue, 02 Aug 2022 18:41:04 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 17:13:22 GMT]]>@olivierlambert,
Is there a simple way to start the VM with PVshim? After googling around I couldn't find anything that would explain how to do this for the non-specialized person.

]]>https://xcp-ng.org/forum/post/51775https://xcp-ng.org/forum/post/51775Tue, 02 Aug 2022 17:13:22 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 16:49:19 GMT]]>@olivierlambert,
This is an x86_64 VM. I originally made the VM on XenServer back when it was Citrix owned. Then I actually migrated it over to KVM about 7 years ago. And then about 3 years ago, I migrated the VM back to XCP-ng using a qcow conversion routine that included running a dracut regenerate command.

dracut --regenerate-all -f && grub2-mkconfig -o /boot/grub2/grub.cfg

I wonder if I could somehow start in recovery mode and use that same command to regenerate the VM?

]]>https://xcp-ng.org/forum/post/51774https://xcp-ng.org/forum/post/51774Tue, 02 Aug 2022 16:49:19 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 16:16:19 GMT]]>So if the issue is clearly inside the guest, then it's might not be related to XCP-ng 🤔

Could it be 32 bits vs 64 bits?

]]>https://xcp-ng.org/forum/post/51773https://xcp-ng.org/forum/post/51773Tue, 02 Aug 2022 16:16:19 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 15:44:42 GMT]]>@olivierlambert , thank you for your reply.

I did switch to HVM, however that's when I get the grub bootloader screen with the Error 13: Invalid or unsupported executable format.

So, PVShim might work in this case? I will give it a shot.

]]>https://xcp-ng.org/forum/post/51772https://xcp-ng.org/forum/post/51772Tue, 02 Aug 2022 15:44:42 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Tue, 02 Aug 2022 07:34:13 GMT]]>I would switch them to HVM if you can, PV is dead. There's PVshim at worst.

]]>https://xcp-ng.org/forum/post/51747https://xcp-ng.org/forum/post/51747Tue, 02 Aug 2022 07:34:13 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Mon, 01 Aug 2022 22:01:36 GMT]]>@Danp ,

The crazy thing is is these are old centos 5.5 vms. They haven't had any patches for ages. Neither have the hosts been patched for quite a while...

That's what I would think too but seems unlikely in this case...

]]>https://xcp-ng.org/forum/post/51740https://xcp-ng.org/forum/post/51740Mon, 01 Aug 2022 22:01:36 GMT<![CDATA[Reply to Error 13: Invalid or unsupported executable format on Mon, 01 Aug 2022 21:48:57 GMT]]>Have you checked your logs (maybe yum.log)? Probably a recent kernel or grub update is causing the issue.

]]>https://xcp-ng.org/forum/post/51739https://xcp-ng.org/forum/post/51739Mon, 01 Aug 2022 21:48:57 GMT