@olivierlambert Yes, Vates is on another level of professionalism. Wow 
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RE: Hosts vs. Pools - Information Required
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RE: DevOps Megathread: what you need and how we can help!
@olivierlambert wow, We'll surely ask many things in this thread. Thank you.
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RE: VM Console Access
this is my code to test console for vms but I am not able to access it. Actually I have to access the console but I do not know how do auth for this.
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RE: User specific data
you saved my life bro, thank you so much. I got the right way.
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RE: Slow SR Creation
Yes multipath is enabled and we have two target ips. When I scan the target it calls the
sr.probeIscsiIqnsmethod and return the iqns in the dropdown as*(ip,ip)and on the select of*(ip,ip)it callssr.probeIscsiLunsmethod. Both method take time to return the response. 90+ LUNs will be listed in the Lun dropdown after 4-5 minutes. Then On selection of LUN with respect to theidit callssr.probeIscsiExiststo validate the LUN, this method also take 1-3 minutes. After all this on create button click if then calls a methodsr.createIscsi. This takes too much time too. I have a pool of 3 hosts and all servers have verified connectives to the SAN Storage. If you need any information regarding this, I will be happy to share. -
Slow SR Creation
The sr.probeIscsiIqns and sr.createIscsi is very slow. I checked the payload too and it send the target, which turned out to be a synthetic "*" (wildcard). Any way to optimize the SR.probe and creation?

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RE: Facing some issue in copy Function of Xen Orchestra
@AtaxyaNetwork Hi, The default timeout for task is 24hrs. I initiated the copy process and it vanished out within 6-7hrs. How can I see the error or issue that is caused?
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Facing some issue in copy Function of Xen Orchestra
We are facing an issue observed multiple times when migrating assets from one server to another. We are using the copy functionality present in Orchestra to copy the VMs from one source to the other. While some have been successful, there have been cases in which the copy disappears during the later phases of it's execution without any error message or manual intervention.
In some cases, data is not completely copied from one place to the other. Can it please be highlighted if this is an issue with the feature or is there a limit cap placed on the amount of machines one can copy on the Servers or Orchestra.
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Xenorchestra V6 issue
Team,
I am facing issue while giving extra storage when i select any Installation source. But when i select storage then it allow me to give size.
XO info: Xen Orchestra, commit 91314

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Windows Server 2025 VM randomly freezes/hangs (loss of VNC + RDP + console) on XCP-ng — reboot required
My Windows Server 2025 Standard VM randomly becomes completely unresponsive. No response via VNC console, RDP, or any network service. The VM shows as "Running" in XO/XCP-ng Center.
RAM/CPU graphs in XO freeze at the last value. No errors or relevant logs in Windows Event Viewer (daemon/kernel), XCP-ng host logs, or hypervisor logs. Only solution is a forced reboot (or power off/on via XO). After reboot, the VM works normally for hours/days until the next freeze.This matches known Windows Server 2025 + Xen issues.
Environment
- Hypervisor: XCP-ng (version: please add yours, e.g. 8.3.x)
- Orchestrator: XO (XOA)
- VM Details (from XO API / XO):
{ "id": "adf48a15-0b02-6fee-21d8-895190077680", "name_label": "<VM name>", "power_state": "Running", "virtualizationMode": "hvm", "os_version": { "name": "Microsoft Windows Server 2025 Standard", "uname": "10.0.26100" }, "CPUs": { "max": 4, "number": 4 }, "memory": { "size": 17179820032 }, "viridian": true, "pvDriversVersion": "9.1.145-77", "pvDriversDetected": true, "managementAgentDetected": true, "management agent": "9.1.145-77", "NIC type": "Realtek RTL8139", "VGA": "cirrus", "boot": { "firmware": "bios", "order": "cd" }, "other": { "base_template_name": "Other install media" } }- Hardware Virtualization: PVHVM with paravirtualization drivers enabled.
- Storage: (please specify: local SR, NFS, iSCSI, etc. + VBD types)
- Network: Realtek RTL8139 (emulated)
Steps Already Taken
- Viridian extensions are enabled (viridian: true).
- Latest XCP-ng Windows PV Drivers + Management Agent 9.1.145-77 installed.
- Windows Server 2025 is fully updated.
- Checked host logs (xl dmesg, journalctl), guest Event Viewer — nothing at the time of freeze.
- VM uses BIOS boot (not UEFI).
Additional Context
The freeze is completely random (no specific workload, time of day, or high load trigger observed).
Reboot always resolves it temporarily.
Similar reports exist for Windows 11 24H2 / Server 2025 on XCP-ng (Viridian synthetic timer, PV drivers, emulated devices).Questions
Are there any known issues with Realtek RTL8139 NIC on Server 2025? Should I switch to a PV network driver / different emulated NIC?
Any recommendations on VGA (cirrus) or other VM settings?
Should I try forcing a kernel memory dump next time it hangs (xl trigger <domid> nmi)?
Any other diagnostics or logs I should collect?Thanks in advance!
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RE: SR.Scan performance withing XOSTOR
@Pilow does SR.scan checks only keep-alive or do any kind of write operation or anything else?
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RE: GPU Virtualization
@olivierlambert is there any official documentation by your team? Will you guys add this officially in xcp-ng?
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GPU Virtualization
Hi,
I have attached an NVIDIA GPU to my host and completed the initial configuration successfully. The GPU is now visible in Xen Orchestra / XenCenter.
Currently, the GPU is fully assigned (passthrough) to a single virtual machine. However, my requirement is to share or virtualize the same GPU across multiple VMs.
I would like to know:
Is it possible to virtualize or share an NVIDIA GPU among multiple VMs in a Xen/XCP-ng environment?
If yes, what techniques or technologies are available to achieve this (e.g., vGPU, SR-IOV, mediated devices, etc.)?What are the prerequisites and limitations (supported GPU models, drivers, licensing requirements)?
Any guidance or best-practice recommendations would be highly appreciated.
