Can TrueNAS Core VMs work with a CPU with EPT only (no UG)?

[benze]

I have TrueNAS-12.0-U6.1 running on a machine with dual Xeon E5530 CPUs. These CPUs have EPT but not UG (unrestricted guest).

Code:

eric@truenas:~ $ grep VT-x /var/run/dmesg.boot
  VT-x: PAT,HLT,MTF,PAUSE,EPT,VPID
  VT-x: PAT,HLT,MTF,PAUSE,EPT,VPID

When I try to setup a new VM, the system warns me that it can only run with a single CPU, single core and single thread.

I have tried setting up a Ubuntu VM with a single CPU, core, thread but it fails to start up at all. I haven't been able to find any logs to indicate what is happening or why, so I suspect that it is the missing UG feature which is causing the issue, however, I have read some threads which indicate that it should work with single CPU settings.

/var/log/messages provides no info of value, no does the /var/log/middleward.log files. The only thing I see is:

2022/09/15 14:41:38] (DEBUG) VMDeviceService.update_device():2053 - Creating ZVOL HomeNAS/VM/UbuntuLTS-rnsb89 with volsize 53687091200


But interestingly enough, I see no files created in /mnt/HomeNAS/VM/UbuntuLTS-rnsb89. Am I expected to see a vdi file or something of the sort at that location?

Code:

root@truenas[/var/log]# ls -al /mnt/HomeNAS/VM
total 1641569
drwxrwxrwx  2 root  wheel          3 Sep 15 14:30 .
drwxr-xr-x  9 root  wheel          9 Sep 15 13:29 ..

Is there any hope for me to get anything working as a VM?

 

[Samuel Tai]

Zvols aren't created under /mnt/HomeNAS/VM. You can find your zvol at /dev/zvol/HomeNAS/VM/UbuntuLTS-rnsb89. However, this thread in the FreeBSD forums indicates CPUs without UG support will only be able to boot FreeBSD guest VMs.

 

[benze]

Zvols aren't created under /mnt/HomeNAS/VM. You can find your zvol at /dev/zvol/HomeNAS/VM/UbuntuLTS-rnsb89. However, this thread in the FreeBSD forums indicates CPUs without UG support will only be able to boot FreeBSD guest VMs.

Ah - thanks for pointing me in the right direction. I figured the zvol had to be somewhere else, but could not figure it out.

Am disheartened to hear about requiring UG for Linux VMs. If I wanted to upgrade my CPU to a X5650+ family however, how can I be sure that it supports UG as well? I have another server running Linux with the X5650, but when I check the flags, I don't see EPT or UG:

Code:

        Family: Xeon
        Manufacturer: Intel            
        ID: C2 06 02 00 FF FB EB BF
        Signature: Type 0, Family 6, Model 44, Stepping 2
        Flags:
                FPU (Floating-point unit on-chip)
                VME (Virtual mode extension)
                DE (Debugging extension)
                PSE (Page size extension)
                TSC (Time stamp counter)
                MSR (Model specific registers)
                PAE (Physical address extension)
                MCE (Machine check exception)
                CX8 (CMPXCHG8 instruction supported)
                APIC (On-chip APIC hardware supported)
                SEP (Fast system call)
                MTRR (Memory type range registers)
                PGE (Page global enable)
                MCA (Machine check architecture)
                CMOV (Conditional move instruction supported)
                PAT (Page attribute table)
                PSE-36 (36-bit page size extension)
                CLFSH (CLFLUSH instruction supported)
                DS (Debug store)
                ACPI (ACPI supported)
                MMX (MMX technology supported)
                FXSR (FXSAVE and FXSTOR instructions supported)
                SSE (Streaming SIMD extensions)
                SSE2 (Streaming SIMD extensions 2)
                SS (Self-snoop)
                HTT (Multi-threading)
                TM (Thermal monitor supported)
                PBE (Pending break enabled)
        Version: Intel(R) Xeon(R) CPU           X5650  @ 2.67GHz     

Should I not expect to see FPT or GU in the list of flags?

Thanks!

Eric

 

[Samuel Tai]

According to this thread, Westmere Xeons (which includes the X5650) support unrestricted guest, but Nehalems (which includes the E5530) don't. You should be OK with the X5650.