Unable to Boot Centos


I received a new Dedicated Server from ovh.com yesterday. I updated the o/s using yum update and also made some changes to kernel parameters to install Oracle as mentioned at http://eduardo-lago.blogspot.com/2012/01/how-to-install-oracle-11g-database.html

When I rebooted the machine it is not coming up. The hosting company does not provide a KVM. It used to provide a Virtual KVM but for some reason it is not available today. I have contacted there support but they are saying to fix the o/s issue myself.

I can access the o/s in Rescue mode and mounted the partition then chroot <mount point>.  I checked grub.conf and looks fine to me:

[root@rescue grub]# cat grub.conf 

	title CentOS (2.6.18-348.6.1.el5)
	kernel /boot/vmlinuz-2.6.18-348.6.1.el5 root=/dev/sda1  ro
	root (hd0,0)
	initrd /boot/initrd-2.6.18-348.6.1.el5.img
	title linux centos5_64
	kernel /boot/bzImage-3.8.13-xxxx-grs-ipv6-64 root=/dev/sda1  ro
	root (hd0,0)

[root@rescue grub]# ll /boot/vmlinuz-2.6.18-348.6.1.el5
-rw-r--r-- 1 root root 2126172 May 21 16:00 /boot/vmlinuz-2.6.18-348.6.1.el5
[root@rescue grub]# ll /boot/initrd-2.6.18-348.6.1.el5.img
-rw------- 1 root root 3629129 Jun 24 14:31 /boot/initrd-2.6.18-348.6.1.el5.img

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Is there a way that I can find without having physical access to the machine why the system is unable to boot?
Who is Participating?
Vijay Pratap SinghConnect With a Mentor Commented:
OVH dont provide physical access i used a lot their service, try to change default = 1 in grub entry and do the hard reboot from the panel provided by OVH manager and please dnt forget to change hdd boot from rescue that you are using the main issue is OVH use their own distributions that  have different kernel. If this doesnt fix the issue you have to reinstall it.

sysautomationAuthor Commented:
I made it default = 1 and the machine is now accessible. But what should I do if I need the vmlinuz-2.6.18-348.6.1.el5 Kernel ? Currently it is following:

uname -a
3.8.13-xxxx-grs-ipv6-64 #3 SMP Fri May 31 13:26:19 CEST 2013 x86_64 x86_64 x86_64 GNU/Linux

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I am using vmlinuz-2.6.18-348.6.1.el5 with my other 2 Dedicated Servers at OVH. Just the difference is they are running with Software RAID and this machine is Hardware RAID.
Vijay Pratap SinghCommented:
Try to reinstall the Kernel and chnage entry in grub.conf if its works it will be great else there might be some conflicts between hardware Raid and this kernel need to check what changes required in Sysctl.conf for this :)
Is your boot device on a md software raid device?
When the bot fails with the new kernel, what is the message?
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