ubuntu 12.04 LTS how to avoid GRUB update‏

[Ralf Mardorf]

On Thu, 14 Jan 2016 08:11:12 +0000 (UTC), Spyros Tsiolis wrote:
>Correct me if I am wrong but AFAIK, "upgrade" means 
>upgrading to a more recent Ubuntu OS version
>while "update" means updating packages for the 
>running / existing version. 

No, you are mistaken.

"update
        update is used to resynchronize the package index files from
        their sources." [1]

IOW it's a refresh of the data base of the available packages. It does
not update packages, it only syncs/updates the index/data base.

"upgrade
        upgrade is used to install the newest versions of all
        packages" [1]

This installs upgraded versions of packages, but before doing this you
need to "update",otherwise the package management (apt) wouldn't know
that there are new packages.

"dist-upgrade
        dist-upgrade in addition to performing the function of
        upgrade, also intelligently handles changing dependencies with
        new versions of packages; apt-get has a "smart" conflict
        resolution system, and it will attempt to upgrade the most
        important packages at the expense of less important ones if
        necessary. So, dist-upgrade command may remove some
        packages." [1]

It's the same as upgrade, but also manages packages as described. It's
not clear to me how recommended packages are handled by both kinds of
upgrade. However, a dist-upgrade might be not needed, but might be
useful, especially when using third party repositories. Theoretically
dist-upgrade is useful for release updates, but usually it's not used
for release upgrades, do-release-upgrade seems to be the recommended
way [2]. I never upgraded from one to another release, so I would have
to read several sources myself, IOW the correctness of [2] might be ok,
or not ok.



[1] http://manpages.ubuntu.com/manpages/precise/en/man8/apt-get.8.html
[2] https://help.ubuntu.com/lts/serverguide/installing-upgrading.html
    https://askubuntu.com/questions/110477/how-do-i-upgrade-to-a-newer-version-of-ubuntu
    http://www.cyberciti.biz/faq/howto-upgrade-to-ubuntu-14-04-from-ubuntu-13-10-or-12-04/