Hello!
Yesterday I got the system warning from the Updater that there's an important security update, and I OKed it and post factum I realized that it was actually an automated kernel upgrade. I also keep on getting messages from the system that I can upgrade to 16.04, but I choose not to for now and one of the main reason is that I'm afraid that PHP7 (which is the default for 16.04) won't do any good to my Joomla script that is hosted on a LAMP stack. Not to the Joomla itself, which is compatible with PHP7, but to what comes with it together. I checked and I'm still on 14.04, PHP 5.5 which is good. Now there are my couple of questions, regarding the situation:
1) What's the advantages of running 14.04 specifically on a new kernel version?
2) Do I have systemd? I think I don't, but I'm not sure. But what I did notice is that now I don't have this boot issue that kinda corrected itself after the kernel upgrade. I mean, I used to have this annoying problem of system not booting properly the first time I turn on the PC. Only after the reboot, I used to get to the Ubuntu login screen. The first time the system used to be dropped into a BusyBox shell environment. So could there be a direct connection between boot process and the new kernel? Does a kernel upgrade can really change it? So far it looks like it, though I've only been booting the system a couple of time, so it might be too early to tell.

It is the kernel that gets loaded after grub/lilo/etc boot loaders pass to init. But it doesn't mean that boot loaders are affected by the change of kernel version.
Kernel is everything in the OS. All programs call for its subsystems. But if the program is calling for different version then there begins your agony towards golgotha. Therefore, if you do not understand fully what is coming up don't upgrade if it ain't broke.
If you are fond of upgrading *whatever*, like a windows M$ panicked user, you will soon meet problems that developers have not yet solved.

To illustrate a simple Gnu/Linux general attitude (this does not apply to many who are bound by job and duty to cope up high security demands) many of us today still run Slackware 10 or 12 without being upgraded for many years now, but we have a fine tuned firewall and well cared using practice; we understand our limits and we know what we are doing. So reading and learning is more helpful than blind upgrade.

Hope that helps. Good luck and enjoy.

m.m.

Thanks for your reply!

I kinda disagree with you in couple of things though. First of all, it was not my decision to upgrade. The Updater didn't inform me that there would be a kernel version upgrade. Secondly, I used to have a very annoying issue of constantly rebooting the system, and considering that I plan to run production servers on it, wasted reboot time is critical for me. More often than not, I couldn't even turn off the system normally, unless I kept on/off button for a few seconds. Otherwise, it all was hanging being half way there, so to speak. Like I said, so far I haven't noticed any issues and I've got a backup from before, so it's gonna take me like 20 minutes to get back to 3.16
I agree with you that upgrading your OS often (every year or two) is a bad idea, but it's not all that often I do that. In my pre-Linux era, I was using XP from 2003 till 2010. 7 years. I skipped Vista altogether. And I've been using W7 from 2010 till last year, so here's your 5 year period. I plan to wait till after 18.04 has been released. By then, we would be approaching 2019 when support for 14.04 ends.

No, you don't have systemd in 14.04
Certainly there is a direct connection between the boot process and the new kernel, because you have to boot the new kernel - therefore grub must be updated anytime a new kernel is installed.

I got the same message, and did the same upgrade, yesterday on one of my two Xubuntu 14.04 boxes. The other box did not get the notification and is still running the older kernel.

Neither of the boxes has full systemd, but both have parts of it. On both, the original upstart login process has been replaced by systemd. I've not seen the problem you describe on either, but it could easily have been something brought on during the replacement (which seems to have taken place, a little at a time, via routine security updates along the way).

I do find it strange that the two boxes, which were nominally identical, now differ in their kernels' major versions. However, the one that upgraded was originally a clean install of 14.04, while the one that did not had been upgraded from 12.04 to 14.04 -- both done a year ago.

The one with the 4.4 kernel does seem to boot a bit faster now than it did before getting the new kernel, but the other one usually runs 24/7 and reboots only when necessary after an upgrade.

Security fixes, new/updated hardware support.
You may have benefitted from the latter.

IMHO, if you have a public facing machine, you need to stay current on all CVEs. That probably means accepting all the updates on Ubuntu LTS.

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