• 0 Votes
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    M
    Hello @anthoineb, Following your suggestion to test a newer blktap release, we installed blktap-3.55.5-9.4.xcpng8.3.x86_64 and matching debuginfo on all three hypervisors. We then fully shut down and started all 21 OpenSearch data VMs, completing this on September 11. We verified that their running tapdisk executables matched the installed binary. Unfortunately, the stall recurred on September 13 on os-ott-data-1-5. For the affected tapdisk process (PID 2797568), we verified during the incident: /proc/2797568/exe pointed to /usr/libexec/tapdisk, without (deleted); its SHA-256 matched the installed executable; GDB loaded matching debug symbols, build ID dc98a78aff623c1cf12518663c859e3efa32413c. Before recovery: guest I/O made no progress; 255 requests were in flight and 256/256 tags were busy; I/O PSI full was approximately 96–97%, with four tasks in D state; tapdisk reported zero outstanding requests. The active td_xenblkif ring showed: req_prod = 866947066 req_cons = 866946810 rsp_prod = 866946810 rsp_prod_pvt = 866946810 nr_ents = 256 Thus, 256 requests were pending in the active PV ring but had not been consumed. After preserving the baseline GDB capture, our recovery controller executed your suggested call once: call (void)tapdisk_xenblkif_sched_chkrng(blkif) The call completed at 09:40:14 MSK (UTC+03:00). By 09:40:25, guest I/O was progressing again, inflight requests and busy tags were zero, and the local OpenSearch API was responding. The post-recovery GDB capture showed all four ring counters equal to 866967322. The node rejoined the cluster at 09:42:00 without restarting OpenSearch or rebooting the VM. So the same ring-processing stall still occurs with the running 9.4 binary, and the explicit ring-check call still restores I/O. We have complete before/after GDB captures and the recovery-call log available. Is there a newer build or a specific scheduler/event-channel state you would like us to capture during the next occurrence?
  • Error: Can't init vhd directory without using alias

    Unsolved Backup
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    1 Votes
    5 Posts
    68 Views
    A
    In any case, rolling back XO to an older build helps, so hopefully it will be fixed soon.
  • VDI export to VMDK results in a corrupted disk

    Unsolved Xen Orchestra
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    0 Votes
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    A
    I tried to export 3 VDIs from 2 different XCP-ng pools. 2 VDIs from Windows Server 2025 VMs and 1 from Windows Server 2022 VM. All 3 VMDKs seem to be corrupted when I try to use them in VMware Workstation. I also tried reimporting 1 of the exported VMDKs back into the XCP-ng repository and the VM booted without any issue using the reimported VDI. Maybe there is either an issue with this VMDK format in VMware Workstation or the XO´s export/import method creates VMDK files that can be exported and reimport back into XCP-ng repository while preserving the original state of the VDI in the XCP-ng repository even if it´s unusable in VMware WS.
  • XO NFS option sec=krb5p encrypted transport

    Xen Orchestra
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    0 Votes
    1 Posts
    30 Views
    No one has replied
  • Master, commit a3139 failing backups

    Solved Backup
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    0 Votes
    21 Posts
    2k Views
    M
    I've just been hit with this also: Can't init vhd directory without using alias All S3 repo's running SeaweedFS, where fine the last time I used them (a few weeks ago). I don't use my xcpng servers on the homelab daily as I move to Unraid. Running Master, commit 99312
  • Date format on web interface: Only US format available?

    Unsolved Compute
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    2 Votes
    11 Posts
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    J
    @julienXOvates said: @acomav We will actually propose to change the date and time format in XO6 settings, so you would be able to choose between : YYYY-MM-DD MM/DD/YYYY DD/MM/YYYY and 12h or 24h time format. Hopefully in one of the next 3 months ! I hope that will answer your need, otherwise let me know ! Thanks for putting this one the roadmap, for one of the next 3 months. That date order issue, has been bugging me as if you are rushed off your feet, may not remember that it’s the US date order. Also fits in more with the rest of European software used, or configured for the European localisation.
  • 0 Votes
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    @johnnezero said: @john.c Thank you for all the great ideas, keep em' comming! Your welcome. If your other plugin was vibe coded it may be worth doing the same for the other. If you’re still working on it! @julienxovates In regards to the XO updates with the upcoming encrypted XO data store, by default (opt in for now). Is it ready for plugins like the one done by this author, and others in the future please?
  • 3 Votes
    3 Posts
    140 Views
    acebmxerA
    v0.7.0 — findings, category extraction, and a Vates support package. Since the last update, log collection has been through a few fixes and gained three new pieces built on top of it. Findings, from two sources. A new Findings page reads the XO API (messages, alarms, tasks, missing patches, backup/restore runs) and also scans a collected bundle for storage failures, multipath issues, XAPI exceptions, HA fencing, OOM kills and clock skew — six log-based rules in total now. When both reports describe the same incident (matched by condition and, if both are timestamped, within an hour of each other) each finding gets a small "confirmed by" badge instead of showing up as two unrelated entries. [image: 1789142072836-screenshot_20260911_115408.png] Individual log categories, pulled out of a bundle already on disk instead of downloading again — XAPI, storage, audit, security, kernel, HA, xenstore, RRD, network, system. Tick categories on the Collect form before collecting, or against an already-stored bundle afterwards. [image: 1789142141211-screenshot_20260911_114713.png] A Vates support package. One .tgz — redacted bundle, findings (MD + JSON), redaction report, inventory, and a manifest of what's inside and what was masked — instead of downloading each piece separately. [image: 1789142174831-screenshot_20260911_114827.png] Dashboard status panels now show findings severity, how many redaction rules are off, storage used, and recent job activity at a glance. [image: 1789142371892-screenshot_20260911_115754.png] Known issue — still unsolved The truncated-download-behind-a-reverse-proxy bug from the last post is not fixed. logs.tgz has no Content-Length (XCP-ng builds it on the fly), and on my own Nginx Proxy Manager deployment the proxy's connection to XO intermittently closes before the last chunk arrives. Two things tried, neither fixed it: proxy_buffering off / proxy_set_header Connection "" — reduced how often it happened, didn't eliminate it. Identical config, run twice back to back, produced one good download and one truncated at the same offset as before. Suppressing httpx's Accept-Encoding: gzip, deflate header (it was asking the proxy to transport-encode an already-gzipped file) — same result, only reduced frequency, not shipped since it doesn't actually fix anything. proxy_http_version 1.1; broke the proxy outright when I tried it, for a reason I don't understand — so that's not the next thing to try either. What XCP Pulse now does about it: reads the archive in streaming order and keeps whatever it read before the stream broke, rather than losing the whole analysis to the last few missing bytes, and says on the report when it ended early. If a collection tells you the bundle ended early, the honest advice is to retry it — not that it's fixed. Documented in docs/installation.md in case someone with more insight into the Nginx/httpx side of this has a fix. Also fixed since v0.6.0 The restricted-account warning on the Collect page was showing on every connection, including admin ones — wrong template condition, not a real permission check. Fixed. The default collection no longer downloads the XAPI audit trail unless you ask for it — xen-bugtool already includes it in the bundle, so it was 770 MiB of duplicate data on every run. Default collection is now the bundle only, ~870 MB / ~3 minutes. XO's /messages and similar routes were being limited from the oldest end, not the newest — a pool with a lot of history could return findings from a month ago and miss everything recent. Now filtered by time window server-side instead. https://github.com/acebmxer/xcp_pulse
  • 0 Votes
    4 Posts
    121 Views
    dthenotD
    @Dan Hello, So our investigation found that this change was introduced with commit https://github.com/xcp-ng/sm/commit/00637dd52e845d6016add9718fc9cc694aec9f0d It was aimed at EXTSR in particular, it appear that the first SR to be plugged is the one choosing the mode of sr-mount since util.makedirs also create the parent directory with the given mode. I have created a card for the issue on our side.
  • Backup remote repository structure

    Backup
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    0 Votes
    2 Posts
    63 Views
    P
    @abudef Hi, Do you think this doc can help you? Link to doc I think it needs some improvements, feel free to enhance it if you feel it is necessary!
  • VIDs are showing up as snapshot, but they are not.

    Unsolved XOSTOR
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    K
    @olivierlambert I'm seeing a recurrence of the snapshot_of / hidden-disks issue after patching to xapi-26.1.16-1.2 (both hosts, rebooted). Unusual element this time: snapshot-fixer.py dry-run flags ~260 VDIs across the SR that all cite a single OpaqueRef which resolves to no VDI (xe vdi-list | grep <ref> returns nothing). Holding off on rewrite until I understand whether that single-dangling-ref pattern is safe, given the set appears to include base VDIs of legitimate snapshots. Full technical detail and questions posted on GitHub: https://github.com/xcp-ng/xcp/issues/844.
  • 0 Votes
    28 Posts
    5k Views
    K
    @poddingue I'm seeing a recurrence of the snapshot_of / hidden-disks issue after patching to xapi-26.1.16-1.2 (both hosts, rebooted). Unusual element this time: snapshot-fixer.py dry-run flags ~260 VDIs across the SR that all cite a single OpaqueRef which resolves to no VDI (xe vdi-list | grep <ref> returns nothing). Holding off on rewrite until I understand whether that single-dangling-ref pattern is safe, given the set appears to include base VDIs of legitimate snapshots. Full technical detail and questions posted on GitHub: https://github.com/xcp-ng/xcp/issues/844.
  • GPU Passthrough

    Management
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    0 Votes
    29 Posts
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    tjkreidlT
    @coolsport00 Sorry about the VMW need for the Cisco product. Sounds like you have a number of constraints, finances being I'm sure one of them! At least you have time on your hands and the means to experiment. You may, als, end up with a number of different platforms to meet your needs. We ran both Sun Microsystems and Red Hat Linux and Microsoft Windows servers, each taking on specific duties. It's far from ideal and probably not very cost-effective, but you do what you have to to get stuff to work.
  • 2 Votes
    4 Posts
    129 Views
    poddingueP
    Pretty cool, @samuelolavo, thanks for clarifying!
  • 2 Votes
    15 Posts
    1k Views
    acebmxerA
    I have received a very long update back from Veeam on my backup issues.... There appears to be another user with similar setup / issue not sure if that user is the OP this post specifically... Hello, Thank you for your patience. The QA team has finished the analysis, and I am going to outline the details as below: 1. CBT Inconsistency Issue Whenever you see the Warning about CBT showing: 2026-08-16 17:37:27.459 00079 ERROR | [XenRpcClient]: Failed ListChangedBlocks. Error: [Task 291af3d7-28c1-15a9-7f13-c6a1a12283e9 (Async.VDI.list_changed_blocks) failed: . SR_BACKEND_FAILURE_460. . Failed to calculate changed blocks for given VDIs. [opterr=Source and target VDI are unrelated]. We can go to the previous run and see that we get reports that the CBT of the previous snapshot is inconsistent and thus removed by XCP: 2026-08-16 09:54:34.120 00004 ERROR | [XenBackupManager]: Failed to retain the data for the snapshot 5a17fb31-2616-4e72-a85c-e235883c8c91 Veeam.Vbf.Common.Exceptions.ExceptionWithDetail: [Task 39c0f25f-e811-ee45-1b0b-e4a9ca9839ae (Async.VDI.data_destroy) failed: . VDI_NO_CBT_METADATA. OpaqueRef:a005d328-6da0-b8b7-34ef-0607ed44c2ed The team has been reviewing and testing, and this is what they see. We send the request for the snapshot to be created, and it is sent to the coordinator: xcp-ng-vyadytkn Aug 16 09:50:08 xcp-ng-vyadytkn SM: [1555017][MainThread] vdi_clone: introduced VDI: OpaqueRef:a005d328-6da0-b8b7-34ef-0607ed44c2ed (5a17fb31-2616-4e72-a85c-e235883c8c91) CBT shows as open and reading fine: Aug 16 09:50:08 xcp-ng-vyadytkn SM: [1555017][MainThread] ['/usr/sbin/cbt-util', 'set', '-n', '/var/run/sr-mount/7911c9c5-5f20-01e1-8b8d-39c6a98a2704/5a17fb31-2616-4e72-a85c-e235883c8c91.cbtlog', '-f', '1'] Aug 16 09:50:08 xcp-ng-vyadytkn SM: [1555017][MainThread] pread SUCCESS But look at how on xcp-ng-host2 the CBT gets marked as inconsistent by XCP, even though it's open and reading: Aug 16 09:51:05 xcp-ng-host2 SM: [1683689][MainThread] Changed Block Tracking metadata is inconsistent for disk 5a17fb31-2616-4e72-a85c-e235883c8c91. The Breakdown: xcp-ng-vyadytkn was the coordinator—the one we talk to, who then passes everything around to the hosts. xcp-ng-host2 was the host that the VM resided on at that time. xcp-ng-host2 is marking the CBT as inconsistent and deleting the snapshot CBT log, which means we cannot reference it on the next run. We do not see anything else interacting with the CBT besides that host. This matches exactly what we see with another client running the same setup. The team successfully replicated the environment, which is configured as follows: VM storage is NFS. The VM is running on a host that is not the coordinator. They have been able to reproduce this behavior occasionally, and the working theory is that the VM host keeps its own tracking separate from the coordinator. Part of the backup process requires the VM host to issue a pause/resume via a process called tapdisk. When it resumes, it pushes a data cache (likely inside the NFS cache), overwriting the CBT reference held by the coordinator server. It acts as a race condition—whoever pushes the CBT data last wins. If the VM host pushes last, it breaks what the coordinator is sending. Next Steps for CBT: The team is working to raise this issue directly with Vates so they can address the race condition. We ask that you also open a Vates ticket if possible to help draw more attention to the bug. We are trying to find ways to code around this race condition in the future, but there are currently no ETAs or guarantees. 2. Synthetic Full Failures (Delilah_ArcFS01) In addition to the CBT bug, the team discovered a separate issue. Recently, the synthetic fulls for Delilah_ArcFS01 have been failing. This appears to be related to the NFS repository: [30.08.2026 00:43:22.856] <24> [0007] Error (1) Failed to execute full transform task [30.08.2026 00:43:22.856] <24> [0007] Error (1) Agent: Failed to process method {Transform.CompileFIB}: NfsFileEx was already stopped. File: [Host:, Mount: [/volume1/veeam], Disk: [Delilah ArcFS01 Backup/Delilah ArcFS01 Backup_2026-08-29T232336.vib], Type: [nfs3 (1)]] (Veeam.Backup.Common.CCppComponentException) [30.08.2026 00:43:22.856] <24> [0007] Error (1) in c++: Failed to execute command Command: READ, Offset: 2523136, Data size: 659456, Chunk size: 131072 [30.08.2026 00:43:22.856] <24> [0007] Error (1) in c++: Failed to read file: Offset: 2523136, Block size: 659456, File: Path: [Host:, Mount: [/volume1/veeam], Disk: [Delilah ArcFS01 Backup/Delilah ArcFS01 Backup_2026-08-29T232336.vib], Type: [nfs3 (1)]], Handle: [01000702080061030000000007fffd5f65840fb20000000000000000150061038a2f7c0b0400610379207c0b], Read chunk size: 131072, Write chunk size: 131072, Read only: true Because it continuously fails during the synthetic full, it eventually causes the snapshot to be lost when retries fail. The team will change this logic in a future update. Action Items for the NFS Issue: To help prevent these snapshot loss failures, could you please provide the logs from the repository NFS (192.168.20.91)? Export the logs from the Veeam server and select the repository host. Provide the results of running this command directly on the Repository host: journalctl --since "30 days ago" > journal_repo.log Temporary Workaround: If you can, please temporarily switch to active fulls instead of synthetic fulls to help stabilize the job. Please let me know if you have any questions, and if you are able to raise that ticket with Vates. They also just responded back with this statment... Regarding the second part of the last email with the noticed Synthetic full issue, I actually would like you to also make this registry entry on the Veeam server and keep synthetic fulls enabled to see if it helps with that issue: Path: HKEY_LOCAL_MACHINE\SOFTWARE\Veeam\Veeam Backup and Replication Name: Nfs3CommandWaitTimeoutSec Type: DWORD Value (In Decimal): 86400
  • 🛰️ XO 6: dedicated thread for all your feedback!

    Pinned Xen Orchestra
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    7 Votes
    265 Posts
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    acebmxerA
    SDN controller documentation link - page not found... XO from sources latest commit - 280c0 [image: 1789054561550-screenshot-2026-09-10-113453.png] [image: 1789054584537-screenshot-2026-09-10-113617.png]
  • 0 Votes
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    poddingueP
    Thanks for the feedback, @dvinni !
  • 0 Votes
    111 Posts
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    P
    @JB @christopher-petzel Thanks for your patience! We are glad it works well!
  • XCP-ng 8.3 updates announcements and testing

    Pinned News
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    1 Votes
    680 Posts
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    B
    @gduperrey Installed on all pools. No issues so far.
  • Broadcom removed public access to VDDK download links

    Unsolved Migrate to XCP-ng
    3
    1 Votes
    3 Posts
    288 Views
    poddingueP
    We are fully aware of Broadcom's decision to stop providing the VDDK library to the cloud community or to reserve its download to some authorized partners and customers. As much as we regret this decision, we have to respect it. Because it impacts users who need to make backups, we are evaluating alternative options to address this situation. We will provide further guidance as this evaluation progresses but can't share more information for now.