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I have Ubuntu Server 12.04.2 LTS installed on a server. After I run

    apt-get update & apt-get upgrade & apt-get dist-upgrade

My kernel version has been changed to linux-image-3.5.0-28-generic. (The original one is linux-image-3.5.0-23-generic)

However, after the above operations, when I run apt-get upgrade or apt-get autoremove or apt-get install ntp(or other package), the shell prints the following error message:

root@network:/boot# apt-get upgrade
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
3 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]? y
Setting up linux-image-3.5.0-28-generic (3.5.0-28.48~precise1) ...
Running depmod.
update-initramfs: deferring update (hook will be called later)
Examining /etc/kernel/postinst.d.
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 3.5.0-28-generic /boot/vmlinuz-3.5.0-28-generic
run-parts: executing /etc/kernel/postinst.d/dkms 3.5.0-28-generic /boot/vmlinuz-3.5.0-28-generic
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 3.5.0-28-generic /boot/vmlinuz-3.5.0-28-generic
update-initramfs: Generating /boot/initrd.img-3.5.0-28-generic
run-parts: executing /etc/kernel/postinst.d/update-notifier 3.5.0-28-generic /boot/vmlinuz-3.5.0-28-generic
run-parts: executing /etc/kernel/postinst.d/zz-update-grub 3.5.0-28-generic /boot/vmlinuz-3.5.0-28-generic
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?).
run-parts: /etc/kernel/postinst.d/zz-update-grub exited with return code 1
Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-3.5.0-28-generic.postinst line 1010.
dpkg: error processing linux-image-3.5.0-28-generic (--configure):
 subprocess installed post-installation script returned error exit status 2
 E: Sub-process /usr/bin/dpkg returned an error code (1)

Does any one have any ideas to get this working? (I don't even know what's wrong with that?) Or how to roll back to the previous Linux kernel version?(Since there is no problem for the previous linux-image-3.5.0-23-generic version.) Thanks!

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Through Google, I have just found what's wrong with that.

Actually, my problem is the same as

since my server is also a diskless NFS-booting server...

The solution for my problem is simple:

Just comment out exec update-grub in the file /etc/kernel/postinst.d/zz-update-grub.

(NFS booting does not need grub.)


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