How to diagnose the problem when VM is not starting

[Egor]

My steps to create virtual machine:
1. Upload image.raw.gz to server.
2. Run command 'gunzip -c image.raw.gz | dd of=/dev/pve/vm-100-disk-1'
3. Start virtual machine.

Suddenly from some moment there is a problem that virtual machine cannot boot from a disk:


Hardware settings:


Summary:



How to diagnose what is the problem?

 

[Egor]

Here is Options section (if needed):

 

[dcsapak]

was your source image really 32GB?
does it change if you first unpack it and then dd it ?

 

[Egor]

was your source image really 32GB?
does it change if you first unpack it and then dd it ?

No, my source is 30Gb.
I will change now lvm disk size from 32Gb to 30Gb and see what happens.

 

[Egor]

was your source image really 32GB?
does it change if you first unpack it and then dd it ?

I tried different configurations for HDD and different sizes (30Gb, 32Gb, 33Gb).
All of them result in the same screen:

 

[JayC]

Try changing your scsi controller type. Your using a virtio disk type so the scsi controller should be virtio SCSI. I had the same thing numerous times. I have it down to a science now

 

[JayC]

Also if your server has its own raid with cache and battery then you should set cache to nocache (from writethrough) as its is already handled by the raid controller. If you try and double cache you will flood the raid cache and lockup all your VM's.

 

[Egor]

Also if your server has its own raid with cache and battery then you should set cache to nocache (from writethrough) as its is already handled by the raid controller. If you try and double cache you will flood the raid cache and lockup all your VM's.

I am using just local-lvm as a storage (i.e. no scsi or nfs). I am struggling for the whole day with different configurations and cache options. Nothing works =(

 

[JayC]

It is possible that by making all the changes you corrupted your image. I did that with my VyOS VM. Wanted to change it to a Virtio disk and it refuses to work so after about 3 or 4 attempts i tried changing back to vmware Scsi and it wouldn't boot anymore so i had to restore it from a backup which was a piece of cake..

 

[JayC]

What is image.raw.gz and how was it created? If it was created as a specific type of disk then you need to replicate what it expects when you create the new vm..

 

[JayC]

I tried different configurations for HDD and different sizes (30Gb, 32Gb, 33Gb).
All of them result in the same screen:
View attachment 4966

Setting the disk size is only for the VM summary view. It has nothing to do with the actual disk.

 

[Egor]

It is possible that by making all the changes you corrupted your image.

No way =)

What is image.raw.gz and how was it created? If it was created as a specific type of disk then you need to replicate what it expects when you create the new vm..

It was a virtual machine in libvirt on Ubuntu.
The thing is that this virtual machine works perfectly when I deploy it on that same libvirt.
What is more disturbing is that I was deploying this exact same image on proxmox and there was no problem.
Maybe I've got this issue after 'apt-get dist-upgrade'. Here is a list of package versions:

Spoiler: Package versions

proxmox-ve: 4.4-76 (running kernel: 4.4.35-1-pve)
pve-manager: 4.4-1 (running version: 4.4-1/eb2d6f1e)
pve-kernel-4.4.35-1-pve: 4.4.35-76
lvm2: 2.02.116-pve3
corosync-pve: 2.4.0-1
libqb0: 1.0-1
pve-cluster: 4.0-48
qemu-server: 4.0-101
pve-firmware: 1.1-10
libpve-common-perl: 4.0-83
libpve-access-control: 4.0-19
libpve-storage-perl: 4.0-70
pve-libspice-server1: 0.12.8-1
vncterm: 1.2-1
pve-docs: 4.4-1
pve-qemu-kvm: 2.7.0-9
pve-container: 1.0-88
pve-firewall: 2.0-33
pve-ha-manager: 1.0-38
ksm-control-daemon: 1.2-1
glusterfs-client: 3.5.2-2+deb8u3
lxc-pve: 2.0.6-2
lxcfs: 2.0.5-pve1
criu: 1.6.0-1
novnc-pve: 0.5-8
smartmontools: 6.5+svn4324-1~pve80
zfsutils: 0.6.5.8-pve13~bpo80

---

I've decided that I will make a different stand tomorrow and test it there.

 

[udo]

Hi,
what kind of guest run inside then VM?

Can you post the output of following commands:

lvs /dev/pve/vm-100-disk-1
fdisk -l /dev/pve/vm-100-disk-1

Udo

 

[Egor]

Hi,
what kind of guest run inside then VM?

Can you post the output of following commands:

lvs /dev/pve/vm-100-disk-1
fdisk -l /dev/pve/vm-100-disk-1

Udo

Sure!

Operating System: CentOS 7.2.15.11 (Core)

Spoiler: lvs /dev/pve/vm-100-disk-1

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
vm-100-disk-1 pve Vwi-aotz-- 32.00g data 93.75

Spoiler: fdisk -l /dev/pve/vm-100-disk-1

Disk /dev/pve/vm-100-disk-1: 32 GiB, 34359738368 bytes, 67108864 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 65536 bytes / 65536 bytes
Disklabel type: dos
Disk identifier: 0x000504b8

Device Boot Start End Sectors Size Id Type
/dev/pve/vm-100-disk-1p1 64 1001953 1001890 489.2M c W95 FAT32 (LBA)
/dev/pve/vm-100-disk-1p2 * 1001954 56000000 54998047 26.2G 83 Linux
/dev/pve/vm-100-disk-1p3 56000001 62914559 6914559 3.3G 82 Linux swap / Solaris

 

[Egor]

I've decided that I will make a different stand tomorrow and test it there.

The virtual machine starts successfully on a different stand, so the problem is in my original stand (but I don't know what the problem is).

 

[LightThiefs]

Did someone else encounter the same problem? The only fix I see Egor mentioning is to use a different computer/install (stand?).