As mentioned in a previous lesson, Ubuntu has stable, Long Term Support (LTS) releases.
You can check your release by typing
lsb_release -aor
cat /etc/issue lsb_release -a gives more nicely formatted output.
For any production application, I recommend only using the lates LTS version available when you’re building your server.
LTS
LTS releases are supported for 5 years, while regular releases are only supported for 9 months.
If you have a 14.04 LTS server and you want to upgrade it to 16.04, that would be called a major release upgrade.
LTS’s are
- Enterprise Focused
- Compatible with New Hardware
- Thoroughly Tested
It’s helpful to understand a bit more about versioning.
Versioning
When developers fix bugs and add features to software, including Operating Systems, they have to keep track of what has been done.
There are loosely agreed upon ways of tracking changes using version control, or versioning.
Ubuntu Versioning
LTS versions are even numbered and have a .04 minor release number. 14.04 and 16.04 are consecutive LTS major releases.
A common model is a major release number, with 1 being the first “production”, followed by a period, with a minor version, followed by a period, then a revision number.
Ubuntu is a little different, using the year and month for the major and minor numbers, and a sequential number for the update or patch release number.
I’m running Ubuntu 16.04.3 LTS Server for the majority of the lessons in this course.
The number can be broken down as follows:
16.04.3
18 Year of Release
04 Month of Release
3 Sequential Update Number
18, being an even numbered major release, means it is an LTS release. All LTS releases have a . 04 minor release number because they’re always released in April. There could be several revisions before the next major release.
Release Cycle
If you’re managing a server, it is important to know the operating system is kept up to date regarding fixing bugs and security issues, as well as to know the organization managing the operating system is responsive to requests for new features.
Ubuntu has a regular patching and release cycle, and is actively supported by full time developers as a well as the open source community.
Releases are done every six months following a planned schedule.
do-release-upgrade
Eventually, your LTS version will become unsupported. Prior to that time, you can use the dorelease-upgrade command to upgrade your server to the next version.
You can, of course, still run
do-release-upgrade after end of support, I just recommend planning ahead and doing it prior to end of support.
You should only do a release upgrade to the next supported version.
You could upgrade from 16.04 to 18.04, but not from 14.04 to 16.04.
If your server is too old to support this method, back up your data, do a clean build of the latest release, and restore your data to the new server.
16.04 to 18.04
The lesson has a video showing a release upgrade from 16.04. to 18.04.
You can’t upgrade to the next release until the first update has been done to it. For example, you can’t run
do-release-upgrade
to go from 16.04.x to 18.04.0. You’ll have to wait until 18.04.1 is released.
This is out of concern for stability in production environments.
By waiting for the first patch cycle, you’re more assured that the release upgrade won’t break anything.
