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virtualisation:proxmox_ve:vms_cts:initial_debugging_vm_created_best_practices

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virtualisation:proxmox_ve:vms_cts:initial_debugging_vm_created_best_practices [2026/04/11 22:27] – removed - external edit (Unknown date) 127.0.0.1virtualisation:proxmox_ve:vms_cts:initial_debugging_vm_created_best_practices [2026/04/12 09:31] (current) – thum
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 +======= Initial debugging of VMs created with best practices =======
  
 +The following tips may be useful if you have created a VM [[vm_best_practices_modern_setup|via this article]].
 +
 +====== Proxmox VE - common dmesg Warnings in KVM/q35 VMs ======
 +
 +These warnings appear in the guest dmesg of a properly configured Proxmox VM
 +(q35, OVMF/UEFI, VirtIO SCSI as per the above "modern best practices") and can safely be ignored.
 +
 +===== SATA/ATA "link down" Messages =====
 +
 +  ata1: SATA link down
 +  ata3: SATA link down
 +  ata4: SATA link down
 +  ata5: SATA link down
 +  ata6: SATA link down
 +
 +The q35 chipset always emulates an AHCI SATA controller with 6 ports —
 +even when only VirtIO SCSI is used. The unused ports simply report
 +"no device found". This is completely normal and harmless.
 +
 +''ata2'' shows ''link up'' because the emulated CD/DVD-ROM drive is attached there.
 +
 +**Verdict:** Safe to ignore.
 +
 +===== shpchp: Slot Initialization Failed =====
 +
 +  shpchp 0000:05:01.0: pci_hp_register failed with error -16
 +  shpchp 0000:05:01.0: Slot initialization failed
 +
 +The Linux Standard Hot-Plug PCI driver tries to register itself on bridges
 +that QEMU/q35 only partially emulates. This causes no functional problems
 +and is a well-known cosmetic issue in KVM virtual machines.
 +
 +**Verdict:** Safe to ignore.
 +
 +===== powernow-k8: Power State Transitions Not Supported =====
 +
 +  powernow-k8: Power state transitions not supported (×12)
 +
 +The guest kernel identifies the CPU as "AMD QEMU Virtual CPU" and loads
 +the legacy ''powernow-k8'' driver, which then discovers that CPU frequency
 +scaling is not supported inside the VM. This is expected behavior when
 +not using the ''host'' CPU type — the VM has no real CPU frequency management.
 +
 +**Verdict:** Safe to ignore.
 +
 +===== snd_hda_intel: No Codecs Found =====
 +
 +  snd_hda_intel 0000:00:1b.0: no codecs found!
 +
 +No audio device is configured in the VM. The driver loads anyway but finds
 +nothing to attach to. Either ignore this, or disable the audio device in
 +the VM configuration to suppress the message.
 +
 +**Verdict:** Safe to ignore, or remove the audio device in VM config.
 +
 +===== What you should also see =====
 +
 +  * ''virtio-scsi'', ''virtio-net'', ''virtio-balloon'' all load cleanly
 +  * UEFI/Secure Boot active, EFI disk detected correctly
 +  * Disk recognized via VirtIO SCSI with Write Cache + FUA/DPO support
 +  * Clean boot in ≤ 3 seconds on a managed Vikings Proxmox VE Ceph Cluster with Hardware post 2025 sans cloud-init
 +
 +===== Summary =====
 +
 +^ Warning ^ Cause ^ Action ^
 +| ''ata1-6: SATA link down'' | Unused ports of q35 AHCI emulation | Ignore |
 +| ''shpchp: Slot initialization failed'' | Partial PCI bridge emulation in QEMU | Ignore |
 +| ''powernow-k8: transitions not supported'' | Legacy CPU freq driver, no scaling in VM | Ignore |
 +| ''snd_hda_intel: no codecs found'' | No audio device configured | Ignore or remove audio |