Since the OH2 Linux openhab2* packages used folder names like /etc/openhab2 we used this opportunity to remove the version out of anything the packages provides, including the name of the package itself. Some files such as openhab-cli didn’t use any version in the naming at all, and therefore haven’t moved anywhere.
Unfortunately, it means that in terms of openHAB 2 and openHAB 3, you cannot install both at the same time and openHAB 2 will not automatically update to openHAB 3, but if you use the commands to install openHAB 3 whilst openHAB 2 is installed, then the configs will copy across automatically.
Backup first
If you’ve got an existing OH2 installation, back it up before you do anything. openhab-cli backup [filepath]/[filename].zip will create a zip file which can be used to restore the same version of openHAB later using openhab-cli restore [filepath]/[filename].zip. Put the file somewhere not related to openHAB, such as your own home directory (e.g. /home/pi/). You should probably do your usual OS backup too to make sure you can get back to where you left off.
Prerequisites
openHAB 3 requires Java 11. Most modern Linux OS have an openjdk-11-jdk package available for you to install but alternative solutions such as Zulu’s OpenJDK (which openHABian can install for you) are available and these may run faster on 32-bit armhf platforms such as the Raspberry Pi.
You must also be on the relevant repository for openHAB, this hasn’t changed for openHAB 3.x so the same instructions for moving to it are still valid.
For DEB based installers (apt), your .list file should contain the line:
deb https://dl.bintray.com/openhab/apt-repo2 stable main
For RPM based installers (yum), your .repo file should contain:
[openHAB-Stable]
name=openHAB Stable
baseurl=https://dl.bintray.com/openhab/rpm-repo2/stable
gpgcheck=1
gpgkey=https://bintray.com/user/downloadSubjectPublicKey?username=openhab
enabled=1
Upgrading
If the install of openHAB 3 detects an existing openHAB 2 install, then it will copy the configurations across and update using those files. There are several major differences between openHAB 2 and 3 which may mean that this will cause issues, let us know if you experience anything strange.
After a successful update, you can use commands like sudo systemctl start openhab (notice no 2 at the end) immediately, but openhab-cli will complain of path errors until you restart your shell session (e.g. by logging out and in).
With openhab2 still installed:
APT (Debian / Ubuntu and derivatives)
sudo apt update
sudo apt install openhab
The system will ask you if you want to remove openhab2 as part of this, and you should respond with “y”. After the install continues it will warn you that several of your configuration files have newer versions, mostly your answer to these should be yes to install the maintainer’s versions, take a note of which files these are as the installer will save them in the same location as “.old” files if you want to copy something specific across.
You can get rid of openHAB2 leftover configuration files by using the sudo apt purge openhab2 command, but this also gets rid of the openhab user, to fix this issue you should follow this with:
sudo apt install --reinstall openhab
sudo openhab-cli reset-ownership
DNF (RedHat, CentOS, Fedora, etc)
sudo dnf --allowerasing install openhab
DNF does not replace configuration files for you by default, have a look at the /var/lib/openhab/ directory and replace any older files with their .rpmnew variant.
YUM (Older RedHat, CentOS, Fedora, etc)
The equivalent command should be:
sudo yum swap openhab2 openhab
YUM does not replace configuration files for you by default, have a look at the /var/lib/openhab/ directory and replace any older files with their .rpmnew variant (particularly reccomended for the /var/lib/openhab/etc directory).
Check to see what packages are installed/removed. These should only be openHAB related.
Fresh installation if you have openHAB 2.x installed already.
A fresh installation will make sure you’re clear of any current incompatibilities caused by the upgrade process.
With your backup file clear of any openHAB path (if it’s in /var/lib/openhab2, move it out the way first), you can use the following commands to get rid of all files related to OH2 and then install OH3. If this is a system without openHAB 2, then just use the update and install commands.
After a successful install, you can use commands like sudo systemctl start openhab (notice no 2 at the end) immediately, but if openhab2 was previously installed then openhab-cli will complain of path errors until you restart your shell session (e.g. by logging out and in).
APT (Debian / Ubuntu and derivatives)
sudo apt purge openhab2
sudo apt update
sudo apt install openhab
YUM or DNF (RedHat, CentOS, Fedora, etc)
sudo dnf remove openhab2
sudo dnf install openhab
Replace “dnf” with “yum” for older Red Hat based OSes.