Cannot Boot CentOS 7 VM After Updating Host CentOS 7 Kernel

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I have something very strange that occurred. After updating the kernel on my host CentOS 7 Dell 2950iii I have found that one of my CentOS 7
guest VMs will no longer boot… it just stops at the grub prompt (a second VM functions just fine). I have no idea why this problem occurred and have been unable to fix it. On google I have found several suggestions as to how to repair grub but so far none have worked. What I
have found so far is this:

grub> ls
(hd0) (hd0,msdos2) (hd0,msdos1)

grub> ls -l (hd0,1) (hd0,msdos2) (hd0,msdos1)
Partition hd0,1: Filesystem type xfs, UUID
250008ab-9fde-4892-a8b7-a38882b1a1448 – Partition start at 1024KiB –
Total size
512000Kib
Partition hd0,msdos2: No known filesystem detected –
Partition start at
513024KiB – Total size 12069888KiB
Partition hd0,msdos1: Filesystem type xfs, UUID
250008ab-9fde-4892-a8b7-a38882b1a1448 – Partition start at 1024KiB –
Total size
512000Kib

So it appears that (hd0,1) and (hd0,msdos1) are the same partition containing the boot directory contents

grub> set root=(hd0,1)
grub> ls -l /
DIR 20151002231139 grub/
DIR 20161013022100 grub2/
10190975 20151219235512 initrd-plymouth.img
40655493 20150403032637
initramfs-0-rescue-6494b5d98adc4f66b0cf4c19a0f6ab66.img
4902656 20150403032703
vmlinuz0-rescue-6494b5d98adc4f66b0cf4c19a0f6ab66
252739 20161010232025 symvers-3.10.0-327.36.2.el7.x86_64.gz
29666884 20161013012551 initramfs-3.10.0-327.36.2.el7.x86_64.img
2965270 20161010231818 System.map-3.10.0-327.36.2.el7.x86_64
126431 20161010231818 config-3.10.0-327.36.2.el7.x86_64
5157936 20161010231819 vmlinuz-3.10.0-327.36.2.el7.x86_64
18119089 20161013022032
initramfs-3.10.0-327.36.2.el7.x86_64kdump.img

Is that (hd0,msdos2) the root partition? If is, has it become corrupted somehow? Can I get this system to boot somehow so that I might fix the grub configuration? So far I have tried something along these lines with out success:

grub> set root=(hd0,msdos2)
grub> linux (hd0,1)/vmlinuz-3.10.0-327.36.2.el7.x86_64 root=(hd0,msdos2)/
grub> initrd initrd-plymouth.img grub> boot

I just get this error:
[ 2.128131] No filesystem could mount root, tried:
[ 2.129038] Kernel panic – not syncing: VFS: Unable to mount root fs on unknown-block(1,0)
[ 2.130537] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
3.10.0-327.36.2.el7.x86_64 #1
[ 2.132017] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011

{remainder of stack dump}

Does anyone have any ideas as to

1.) How to fix the problem?
2.) Why the problem occurred in the first place?
3.) How to go about debugging the problem?

I would really like to know how this problem could have occurred on the
1 VM but the Host and 2nd Guest are just fine?

Thanks for your help.

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