Installation of Windows Server 2025 on KVM Hypervisors in bootloop

[sourceYan]

Hi CS Community,

on a fresh setup with CS 4.21.0.0 and Alma Linux 9 KVM (9.1.0), i can't boot into the Windows Setup.

The VM boot from iso with "Loading files..." and then appear for 1 sec. the Windows Logo and the VM boot over again.
I tried to F8 the system do on the bootloader "Don't restart on error" - but it don't work.

Checksum of the ISO is good (tested also the eval iso from MS)
Everything in CS is default, no UEFI or Secure boot in the moment.
Windows Server 2022 will run/install successfully.

Any ideas? =)

[sourceYan]

qemu-vm logfile on the host is:

2025-09-25 05:50:08.406+0000: starting up libvirt version: 10.10.0, package: 7.7.el9_6.alma.1 (AlmaLinux Packaging Team <[email protected]>, 2025-09-17-05:06:48, ), qemu version: 9.1.0qemu-kvm-9.1.0-15.el9_6.9.alma.1, kernel: 5.14.0-570.44.1.el9_6.x86_64, hostname: kvm01a.cloudstack.lab LC_ALL=C \ PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin \ HOME=/var/lib/libvirt/qemu/domain-11-i-2-19-VM \ XDG_DATA_HOME=/var/lib/libvirt/qemu/domain-11-i-2-19-VM/.local/share \ XDG_CACHE_HOME=/var/lib/libvirt/qemu/domain-11-i-2-19-VM/.cache \ XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain-11-i-2-19-VM/.config \ /usr/libexec/qemu-kvm \ -name guest=i-2-19-VM,debug-threads=on \ -S \ -object '{"qom-type":"secret","id":"masterKey0","format":"raw","file":"/var/lib/libvirt/qemu/domain-11-i-2-19-VM/master-key.aes"}' \ -machine pc-i440fx-rhel7.6.0,usb=off,dump-guest-core=off,memory-backend=pc.ram,acpi=on \ -accel kvm \ -cpu qemu64,hv-time=on \ -m size=8388608k \ -object '{"qom-type":"memory-backend-ram","id":"pc.ram","size":8589934592}' \ -overcommit mem-lock=off \ -smp 4,sockets=1,dies=1,clusters=1,cores=4,threads=1 \ -uuid d7621509-013d-41db-aed9-a200dd829032 \ -smbios 'type=1,manufacturer=Apache Software Foundation,product=CloudStack KVM Hypervisor,serial=d7621509-013d-41db-aed9-a200dd829032,uuid=d7621509-013d-41db-aed9-a200dd829032' \ -no-user-config \ -nodefaults \ -chardev socket,id=charmonitor,fd=45,server=on,wait=off \ -mon chardev=charmonitor,id=monitor,mode=control \ -rtc base=localtime \ -no-shutdown \ -boot strict=on \ -device '{"driver":"piix3-usb-uhci","id":"usb","bus":"pci.0","addr":"0x1.0x2"}' \ -device '{"driver":"virtio-serial-pci","id":"virtio-serial0","bus":"pci.0","addr":"0x4"}' \ -blockdev '{"driver":"file","filename":"/mnt/797fe666-3e97-3ec5-be39-89ec2080f44f/f38b1695-5f18-4295-93d6-ae88bdbab295","node-name":"libvirt-2-storage","auto-read-only":true,"discard":"unmap","cache":{"direct":true,"no-flush":false}}' \ -blockdev '{"node-name":"libvirt-2-format","read-only":false,"cache":{"direct":true,"no-flush":false},"driver":"qcow2","file":"libvirt-2-storage","backing":null}' \ -device '{"driver":"ide-hd","bus":"ide.0","unit":0,"drive":"libvirt-2-format","id":"ide0-0-0","bootindex":2,"write-cache":"on","serial":"f38b16955f18429593d6"}' \ -blockdev '{"driver":"file","filename":"/mnt/9673ce91-6cd7-3d04-8999-9965c0156a5d/208-2-d0e38aa9-ad95-305a-a36d-90e8c56075fc.iso","node-name":"libvirt-1-storage","read-only":true}' \ -device '{"driver":"ide-cd","bus":"ide.1","unit":0,"drive":"libvirt-1-storage","id":"ide0-1-0","bootindex":1}' \ -netdev '{"type":"tap","fd":"46","id":"hostnet0"}' \ -device '{"driver":"e1000","netdev":"hostnet0","id":"net0","mac":"02:01:00:cd:00:09","bus":"pci.0","addr":"0x3"}' \ -chardev pty,id=charserial0 \ -device '{"driver":"isa-serial","chardev":"charserial0","id":"serial0","index":0}' \ -chardev socket,id=charchannel0,fd=44,server=on,wait=off \ -device '{"driver":"virtserialport","bus":"virtio-serial0.0","nr":1,"chardev":"charchannel0","id":"channel0","name":"org.qemu.guest_agent.0"}' \ -device '{"driver":"usb-tablet","id":"input0","bus":"usb.0","port":"1"}' \ -audiodev '{"id":"audio1","driver":"none"}' \ -object '{"qom-type":"tls-creds-x509","id":"vnc-tls-creds0","dir":"/etc/pki/libvirt-vnc","endpoint":"server","verify-peer":true}' \ -vnc 10.20.10.11:2,password=on,tls-creds=vnc-tls-creds0,audiodev=audio1 \ -device '{"driver":"cirrus-vga","id":"video0","bus":"pci.0","addr":"0x2"}' \ -device '{"driver":"i6300esb","id":"watchdog0","bus":"pci.0","addr":"0x6"}' \ -watchdog-action none \ -device '{"driver":"virtio-balloon-pci","id":"balloon0","bus":"pci.0","addr":"0x5"}' \ -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \ -msg timestamp=on 2025-09-25 05:50:08.407+0000: Domain id=11 is tainted: high-privileges 2025-09-25 05:50:08.408+0000: Domain id=11 is tainted: deprecated-config (machine type 'pc-i440fx-rhel7.6.0') 2025-09-25 05:50:08.408+0000: Domain id=11 is tainted: deprecated-config (CPU model 'qemu64') char device redirected to /dev/pts/0 (label charserial0) 2025-09-25T05:50:09.682433Z qemu-kvm: warning: Machine type 'pc-i440fx-rhel7.6.0' is deprecated: machines from the previous RHEL major release are subject to deletion in the next RHEL major release 2025-09-25T05:50:09.683656Z qemu-kvm: warning: CPU model qemu64-x86_64-cpu is deprecated -- use at least 'Nehalem' / 'Opteron_G4', or 'host' / 'max' 2025-09-25T05:50:09.699997Z qemu-kvm: -device {"driver":"cirrus-vga","id":"video0","bus":"pci.0","addr":"0x2"}: warning: 'cirrus-vga' is deprecated, please use a different VGA card instead

but no new log event if the reboot occurs.

[weizhouapache]

@sourceYan
you can try

• stop the vm
• add a vm setting guest.cpu.mode=host-passthrough
• start the vm again

[weizhouapache]

I think the default CPU (qemu64) may be not supported by Windows Server 2025

[sourceYan]

Can i adjust the "profile" Windows Server 2025 with this setting so every new VM Deployed get this option by default?

[weizhouapache]

Can i adjust the "profile" Windows Server 2025 with this setting so every new VM Deployed get this option by default?

yes, you can add the same setting to the template

[sourceYan]

thanks again!
But only with ISO install it's not possible? for example to set this in a offering or the guest-OS settings?
So i have to create a Template for that?

[weizhouapache]

you can configure it in agent.properties, but it will affect all vms