Unabele to boot CloudLinux on KVM after update

[Fariborz Navidan <md...@gmail.com>]

Hello,

After updating kernel of a CoudLinux VM to
3.10.0-962.lve1.5.25.10.el7.x86_64 I get the following message on the VM:

panic: not syncing: VFS: Unable to mount root fs on unknown block(0,0)

When I try to boot from older kernel it drops into emergency mode which has
access to all mount points but no service is available. I have submitted
ticket to CloudLinux but their L1 and L2 support was unable to fix and has
escalated the issue to L3. The VM is a production environment for cPanel
hosting.

If you know any point or tip, please let me know.

Best Regards.

Re: Unabele to boot CloudLinux on KVM after update

["Riepl, Gregor (SWISS TXT)" <Gr...@swisstxt.ch>]

> Usually indicates missing storage driver in initramfs (if you were on
> VMware, I would tell you to check if vmw_pvscsi.ko is present in
> initramfs).

First thing to check would be to compare the list of PCI devices
(lspci) and storage devices (cat /proc/partitions) between the older
and the newer kernel. Also, check dmesg for any errors.

If that doesn't work, try to boot into a rescue system, mount the
rootfs, chroot, then regenerate the initrd. I've found that the update
process in CentOS fails sometimes, rendering the system unbootable.
Regenerating the initrd or reinstalling the kernel package usually
helps.

Re: Unabele to boot CloudLinux on KVM after update

[Andrija Panic <an...@gmail.com>]

Fariborz,

Usually indicates missing storage driver in initramfs (if you were on
VMware, I would tell you to check if vmw_pvscsi.ko is present in initramfs).

I've hard time believing that you might be missing initramfs completely
(thought it might happen) but still would advise to re-check.

If OS in general us not damaged, you should be able to still boot older
kernel ?

Regards
Andrija

On Sun, Jun 9, 2019, 22:47 Fariborz Navidan <md...@gmail.com> wrote:

> Hello,
>
> After updating kernel of a CoudLinux VM to
> 3.10.0-962.lve1.5.25.10.el7.x86_64 I get the following message on the VM:
>
> panic: not syncing: VFS: Unable to mount root fs on unknown block(0,0)
>
> When I try to boot from older kernel it drops into emergency mode which has
> access to all mount points but no service is available. I have submitted
> ticket to CloudLinux but their L1 and L2 support was unable to fix and has
> escalated the issue to L3. The VM is a production environment for cPanel
> hosting.
>
> If you know any point or tip, please let me know.
>
> Best Regards.
>