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Enigma12
November 30th, 2014, 06:38 PM
Starting with an update/upgrade a month or so ago, I now have Grub appear at boot-up. Before that update/upgrade, it had never appeared. The only operating system on this computer is Lubuntu 14.04.1 LTS -- NO dual booting. I did, however, initially install Lubuntu 13.10 back in April 2014 and upgraded online a few times to get me to 14.04.1.

If I hit the Enter key or ignore the screen, it just boots to my familiar Lubuntu log-in and desktop, so it's not a real problem. It just seems an unnecessary addition to the boot process.

If I down arrow to "Advanced options for Ubuntu" on the first screen, I see what I suppose are four kernals or parts of them. Since I imagine that the earlier kernals are either vulnerable or less capable, I use the most current one. If these older kernels are unneeded or unsafe, should I delete them? If so, exactly how do I do that?

Again, this is NOT a major problem. It just seems pointless. One of the first things that impressed me about Lubuntu was the very fast boot-up (less than a minute on a 2.8 GHz computer) to full readiness and fast shut-down (7 seconds). Shut-down is still 7 seconds; I'd like to have back my quicker boot-up and remove unneeded files or kernels or whatevers(?) that should be removed.

258291258292

Thanks in advance for any help and advice on this.

Impavidus
November 30th, 2014, 07:33 PM
In a default single boot install the grub menu is hidden. It is not hidden in a dual boot install and boot repair also unhides it. If you wish, you can modify /etc/default/grub to make the menu visible for a shorter time or, setting the timeout to zero, skip the menu completely. This will make it a bit harder to get to the menu if you one day need it. (You'll have to hit shift.)

Older kernels may be somewhat less secure or less capable (although it may make no difference at all on your system), but it's best to keep one old kernel at all times, so you can boot in case the latest kernel breaks. So keep 3.13.0-39 and 3.13.0-40, remove the others using the package manager. Autoremoving old packages may be all that is needed. Else, uninstall all packages with in their name one of the old version numbers.

oldfred
November 30th, 2014, 07:36 PM
I prefer to keep 2 kernels, one current and one older one just as a backup.
And I prefer to use synaptic, if you do not have it:
sudo apt-get install synaptic

Determine your current kernel:
uname -a

In synaptic search for linux-image to choose to delete old ones
Using synaptic
http://ubuntuforums.org/showthread.php?t=1283521

Other housecleaning:

RecoverLostDiskSpace
https://help.ubuntu.com/community/RecoverLostDiskSpace
HOWTO: Recover Lost Disk Space - drs305
http://ubuntuforums.org/showthread.php?t=1122670
http://ubuntuforums.org/showthread.php?t=898573
HOWTO: Cleaning up all those unnecessary junk files...
http://ubuntuforums.org/showthread.php?t=140920
Caution deborphan will delete anything you manually installed. See comment:
Better to use Synaptic to select the ones you no longer want. Also you get notified about dependencies to be removed and can reconsider, if need be.
http://lifehacker.com/5817282/what-kind-of-maintenance-do-i-need-to-do-on-my-linux-pc

With a single install, grub menu should not appear. It does have settings that if an issue on shutdown, it will load menu so you could use recovery mode, if needed.

Post this:

cat /etc/default/grub

I do change my timeout to 3 from normal 10, I do not suggest 0 as then you may not be able to get into grub menu for recovery mode if needed.

GRUB_TIMEOUT=3

mastablasta
December 1st, 2014, 10:15 AM
even if timeout is 0 it should still popup if you hold the left shift key.

and yes grub menu is no pointless as it provides an easy way to system recovery. e.g. kernel update that has gone wrong etc.

mrgs
December 1st, 2014, 10:22 AM
Autoremoving old packages may be all that is needed.

Yes, a reboot and sudo apt-get autoremove normally does the trick. It deletes all but the latest two kernels. The command gives you a warning before the actual deletion begins so you know exactly what is going to go.