Not booting into CloudLinux Kernel

[harry]

Issue when installing CloudLinux on cPanel Xen VPS

[harry]

Hi,

I have successfully upgraded my entire fleet to CloudLinux. However, there is an issue with a cPanel Xen CentOS VPS I have.

After running the CloudLinux install script with a legitimate license and rebooting, the kernel is not switching to CloudLinux:

root@cpanel013 [~]# uname -r
2.6.18-194.26.1.el5xen

Can somebody please provide assistance here? I am relatively new to this so assistance is greatly appreciated.

Thanks, Harry.

[iseletsk]

Could you post content of:
/boot/grub/grub.conf

Most likely you are on paravirtualized VM, and you will need to use PvGrub or PyGrub to get it working.

[harry]

Hi Igor,

Thanks for a very speedy response. This seems to be a very strange one and sometimes I get the feeling this server is running CL, but the kernel suggests otherwise.

--
root@cpanel013 [~]# cat /boot/grub/grub.conf
default=0
timeout=10
title CloudLinux Server (2.6.18-294.26.1.el5.lve0.8.18xen)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-294.26.1.el5.lve0.8.18xen console=xvc0 root=/dev/sda1 ro
initrd /boot/initrd-2.6.18-294.26.1.el5.lve0.8.18xen.img
title CloudLinux Server (2.6.18-294.26.1.el5.lve0.7.49xen)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-294.26.1.el5.lve0.7.49xen console=xvc0 root=/dev/sda1 ro
initrd /boot/initrd-2.6.18-294.26.1.el5.lve0.7.49xen.img
title CentOS (2.6.18-194.26.1.el5xen)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-194.26.1.el5xen console=xvc0 root=/dev/sda1 ro
initrd /boot/initrd-2.6.18-194.26.1.el5xen.img
--

However, despite uname -r showing 2.6.18-194.26.1.el5xen, in WHM its reporting the following:

CLOUDLINUX 5.5 x86_64 xenpv on cpanel013

[iseletsk]

is there control panel for starting/stopping VM?

I think there should be a way to specify if it is using pygrub, or not in there.
So, sometimes when you restart without pygrub -- it would go into using host kernel.
Yet, when running with pygrub -- it would run ours.
Can that be the case?

[harry]

Im running SolusVM... are you referring to this part of the VPS configuration file? I manage this node and virtualize it so I have full access.

kernel = /boot/solus-vmlinuz
ramdisk = /boot/solus-initrd.img
#bootloader = /usr/bin/pygrub

Excuse my incompetence here.

[iseletsk]

yep, that is the one. Uncomment bootloader line and try restarting.

[harry]

Igor, this is genius stuff, thank you so much!

root@cpanel013 [~]# uname -r
2.6.18-294.26.1.el5.lve0.8.18xen

Not sure why I didn come here before, lovely support.

Have a nice day.

[baonq]

I also have a similar problem but I am using the HyperVM control panel with XEN virtualization. Ive added "bootloader = /usr/bin/pygrub\" to VPS configuration file but VPS not boot !

Help me !

[baonq]

> Harry Perks wrote:
> Hi,
>
> I have successfully upgraded my entire fleet to CloudLinux. However, there is an issue with a cPanel Xen CentOS VPS I have.
>
> After running the CloudLinux install script with a legitimate license and rebooting, the kernel is not switching to CloudLinux:
>
> root@cpanel013 [~]# uname -r
>
> 2.6.18-194.26.1.el5xen
>
> Can somebody please provide assistance here? I am relatively new to this so assistance is greatly appreciated.
>
> Thanks, Harry.

I also have a similar problem but I am using the HyperVM control panel with XEN virtualization. Ive added "bootloader = /usr/bin/pygrub\" to VPS configuration file but VPS not boot !

Help me !

[m.hoffs]

do u have a valid /boot/grub/menu.lst file ?

If not try:
# yum install grub
# yum install kernel-xen

After that reinstall cloudlinux kernel and make it default.

[iseletsk]

HyperV is different. It doesn use PyGrub, but usually fails on new install due to lack of integration components. More info here:

https://helpdesk.cloudlinux.com/index.php?/Knowledgebase/Article/View/59/0/hyper-v--vm-fails-to-boot-after-it-was-converted-to-cloudlinux

[baonq]

Content file "/boot/grub/menu.lst" :

default=0

timeout=5

hiddenmenu

title CloudLinux (2.6.18-338.12.1.el5.lve0.8.34)

root (hd0)

kernel /boot/vmlinuz-2.6.18-338.12.1.el5.lve0.8.34 ro root=/dev/sda1 selinux=0

initrd /boot/initrd-2.6.18-338.12.1.el5.lve0.8.34.img

title CentOS (2.6.18-194.32.1.el5)

root (hd0)

kernel /boot/vmlinuz-2.6.18-194.32.1.el5 ro root=/dev/sda1

initrd /boot/initrd-2.6.18-194.32.1.el5.img

title CentOS (2.6.18-194.32.1.el5xen)

root (hd0)

kernel /boot/vmlinuz-2.6.18-194.32.1.el5xen ro root=/dev/sda1

initrd /boot/initrd-2.6.18-194.32.1.el5xen.img

title CentOS (2.6.18-194.8.1.el5xen)

root (hd0)

kernel /boot/vmlinuz-2.6.18-194.8.1.el5xen ro root=/dev/sda1

initrd /boot/initrd-2.6.18-194.8.1.el5xen.img

Ive added "bootloader = /usr/bin/pygrub\" to VPS configuration file but VPS not boot !

How do I switch pygrub mode on HyperVM settings ?

[info]

Hi,

I am trying to install CloudLinux on a cPanel VPS running on a XEN PV virtualization. As discussed above, I tried to use PyGrub kernel in VPS. But after changing the kernel, VPS does not boot.
When I change the kernel back, it boots again.

I cannot find the grub.conf and menu.lst files on the VM. But still VM boots.

The following error is encountered with PyGrub:
Traceback (most recent call last):
File "/usr/bin/pygrub", line 691, in ?
chosencfg = run_grub(file, entry, fs)
File "/usr/bin/pygrub", line 545, in run_grub
g = Grub(file, fs)
File "/usr/bin/pygrub", line 203, in __init__
self.read_config(file, fs)
File "/usr/bin/pygrub", line 402, in read_config
if self.cf.filename is None:
AttributeError: Grub instance has no attribute cf
No handlers could be found for logger "xend"
Error: Boot loader didn return any data!

Any help would be really appreciated!

Thanks!

[mark]

Hi,

I too have the same problem.

I have a VPS running in Xen (SolusVM).

I uncommented the bootloader in VM config as such:
kernel = /boot/solus-vmlinuz
ramdisk = /boot/solus-initrd.img
bootloader = /usr/bin/pygrub

My grub says this:

# cat /etc/grub.conf
default=0
timeout=5
title CloudLinux Server (2.6.18-408.el5.lve0.8.58xen)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-408.el5.lve0.8.58xen console=xvc0 root=/dev/sda1 ro
initrd /boot/initrd-2.6.18-408.el5.lve0.8.58xen.img

However it is still says:
# uname -r
2.6.18-308.el5xen

I did follow the guide here:

https://helpdesk.cloudlinux.com/index.php?/Knowledgebase/Article/View/78/0/how-do-i-configure-cloudlinux-kernel-on-pv-xen

Although, I have quite a few kernels installed, so I don know which ones to remove.
# rpm -qa|grep kernel
kernel-xen-2.6.18-308.4.1.el5
kernel-xen-2.6.18-408.el5.lve0.8.58
kernel-headers-2.6.18-408.el5.lve0.8.58
kernel-xen-2.6.18-308.1.1.el5

Any help will be appreciated.