Before every software installation, Calaos OS automatically records the complete state of the system. If an update goes wrong, you can restart on the previous state and get a working server back.
You have nothing to do for these restore points to exist: they are created on their own. See Rolling back.
Calaos OS updates are incremental: only the components that changed are downloaded and replaced. You never need to make a new USB stick or reinstall.
Your configuration is not affected by an update. Your inputs/outputs, rules, scenarios and measurement history are kept unchanged.
Back up your configuration: it is quick and will save you trouble one day. The procedure is on Backing up your configuration.
Also pick a moment when an interruption will bother nobody. During the update your home automation may stop responding for a few moments, and a restart is sometimes needed at the end.
The update is started from the server. The simplest way is to connect remotely from your everyday computer.
Open a terminal — the Terminal application on macOS and Linux, PowerShell or Windows Terminal on Windows — and type:
ssh root@YOUR_SERVER_ADDRESS
replacing YOUR_SERVER_ADDRESS with the IP address of your server. The password is the one you set in Changing the passwords.
You can also plug a keyboard and a screen directly into the server and type the commands there. It is less convenient, but works exactly the same.
Type:
calaos-os check-update
This command changes nothing: it only checks whether new versions exist and shows them to you. You can run it as often as you like, with no risk at all.
If nothing is available, your server is up to date and there is nothing else to do.
Type:
calaos-os upgrade
The download starts, then the installation. Many lines scroll past: that is normal, it is the detail of what is being installed. You do not have to read them.
Do not close the window and do not cut the power until the command has finished. Depending on the number of components to update and the speed of your connection, allow from a few minutes to about twenty.
It is done when the scrolling stops and the terminal hands control back to you, showing a prompt waiting for your next command.
Go back to using your installation normally: switch on a light from the mobile application, check that a scenario triggers. If everything responds as before, the update succeeded.
If the server needs a restart, restart it:
reboot
Do not reinstall anything and do not panic: this is exactly the situation restore points exist for. Go to Rolling back, which brings you back to the state before the update in a few minutes.
If the server still boots but one particular service no longer works, the Something went wrong page will help you identify which one.
See what is installed, including versions:
calaos-os list
Update a single component rather than everything:
calaos-os upgrade PACKAGE_NAME
Use the Debian tools. As Calaos OS is based on Debian, the apt tool also works and acts on the same package repository:
apt update
apt full-upgrade
The result is the same, and restore points are created either way.
All the commands of the tool are detailed in The calaos-os tool.