Why am I not getting the Ubuntu 18.04 upgrade?
A thorough guide for upgrading is presented here. Other answers already mention you need to use:
do-release-upgrade -d # Use this until 18.04.1 comes out
do-release-upgrade # Use this after 18.04.1 comes out
Additionally though you need to check the file:
~$ cat /etc/update-manager/release-upgrades
# Default behavior for the release upgrader.
[DEFAULT]
# Default prompting behavior, valid options:
#
# never - Never check for a new release.
# normal - Check to see if a new release is available. If more than one new
# release is found, the release upgrader will attempt to upgrade to
# the release that immediately succeeds the currently-running
# release.
# lts - Check to see if a new LTS release is available. The upgrader
# will attempt to upgrade to the first LTS release available after
# the currently-running one. Note that this option should not be
# used if the currently-running release is not itself an LTS
# release, since in that case the upgrader won't be able to
# determine if a newer release is available.
Prompt=never
If the last line says "never" change it to "normal" for Ubuntu 17.10 users. For Ubuntu 16.04 LTS users, change it to "LTS". Otherwise you will get the upgrade...um "never":
rick@alien:~$ do-release-upgrade
Checking for a new Ubuntu release
No new release found.
───────────────────────────────────────────────────────────────────────────────────────────
rick@alien:~$ do-release-upgrade -d
Checking for a new Ubuntu release
Upgrades to the development release are only
available from the latest supported release.
───────────────────────────────────────────────────────────────────────────────────────────
rick@alien:~$ do-release-upgrade -c
Checking for a new Ubuntu release
No new release found.
These commands were issued with Prompt=never under Ubuntu 16.04 where it is available for upgrading yesterday (April 28, 2018). Changing the prompt to lts solved the problem.
You should either backup your data first or clone your data and run the upgrade in a test environment. Here is one script I wrote for such a purpose (but you can also do it manually with Live USB): Bash script to clone Ubuntu to new partition for testing 18.04 LTS upgrade
I made some notes during the upgrade process and here is what you can look forward to:
Step 1: confirmation to proceed: Press [ENTER]
Step 2: packages will be removed: Y
Step 3: replace '/etc/systemd/longind.conf': Y
Step 4: Configuration file '/etc/sane.d/dll.conf', default N, take Y
Step 5: Configuration file '/etc/NetworkManager/conf.d/default-wifi-powersave-on.conf' Take default N
Step 6: Configuration file '/etc/pulse/default.pa' default N, take Y
Step 7: Configuration file '/etc/grub.d/30_os-prober'' default N, take N
Step 8: Full screen grub menu config appears. Take option: keep the local version currently installed
Step 9: Configuration file '/etc/cron.d/anacron', default N, take Y to see what
Error Message multiple times: /sbin/ldconfig.real: Warning: ignoring configuration file that cannot be opened: /etc/ld.so.conf.d/x86_64-linux-gnu_EGL.conf: No such file or directory
Step 10: Non-standard: Configuration file '/etc/vnstat.conf' (display differences 1.13 vs 1.18) take Y
Step 11: 220 packages are going to be removed. (can take hours) enter Y
Step 12: To finish the upgrade, a restart is required. Take Y
Note your steps will vary depending on software installed.
All the more reason for cloning is you can test what happens when you accept default of N or you use Y to get the most current configuration which may or many not be better.
Because your original Ubuntu version is left intact you can run the diff command against the new 18.04 configuration files if you chose to install them.
The Release Notes have this:
Upgrading from Ubuntu 16.04 LTS or 17.10
Upgrades from 17.10 will not be enabled until a few days after 18.04's release. Upgrades from 16.04 LTS will not be enabled until a few days after the 18.04.1 release expected in late July.
All the meta information hasn't been released/configured yet. You can wait a few days or run this as an alternative now:
$ do-release-upgrade -d
It works flawlessly!
The -d is for the latest development release which is the current Ubuntu 18.04 LTS release. The same one referred in the release notes.