Upgrading and rolling back

Upgrade

The newest release, in one step — the same install.sh as a first install, which sees nexovue is already there:

curl -fsSLO https://github.com/nexovue-tech/nexovue/releases/latest/download/install.sh
sudo bash install.sh

Or by hand: an upgrade runs from the new version's kit, which carries that version's Compose files:

tar -xzf nexovue-X.Y.Z.tar.gz
cd nexovue-X.Y.Z
sudo ./nexovue upgrade

From an offline bundle, the same with --offline.

In order, it:

checks the machine, and downloads (or loads) the new images while the old version keeps running;
compares the database schema each version carries — read from the images themselves;
takes a backup, shipped off the server if backups are set up (backup);
switches to the new version, which prepares the databases first and then starts every service;
waits until every service is healthy.

nexovue is unavailable from step 4 until step 5 finishes, usually a minute or two. Telemetry sent in that window is refused with a retryable error, and OpenTelemetry exporters send it again.

Read the release notes before upgrading: they say when an upgrade changes the database schema and how long its migration may take on a large install.

Roll back

sudo /opt/nexovue/current/nexovue rollback

returns to the version that ran before the last upgrade. How depends on what the upgrade changed:

The schema did not change. The older version runs against the same databases: nothing is lost, and the rollback takes a minute.
The schema changed. The older version may not run against the newer schema, so rollback refuses and says so. Going back means restoring the backup taken just before the upgrade:
```
sudo /opt/nexovue/current/nexovue rollback --restore
```
Everything recorded since the upgrade is lost — telemetry, and any change made in the console. It asks you to type the console's address before it touches anything.

nexovue status shows the previous version and whether its schema matches.

Only one step back is kept: after a rollback, rollback has nothing further to return to. Every installed version's kit stays in /opt/nexovue/releases/ until you delete it; delete only versions that are neither current nor previous.

When an upgrade fails

If a service does not become healthy, the upgrade stops and names it, and the services that did start keep running. nexovue status and the service's log (install) show why. Either fix the cause and run the upgrade again, or roll back as above.