Upgrading your Core Lightning node is the same as installing it. So if you previously installed it using a release binary, download the latest binary in the same directory as before. If you previously built it from the source, fetch the latest source and build it again.
Upgrades to Core Lightning often change the database: once this is done, downgrades are not generally possible. By default, Core Lightning will exit with an error rather than upgrade, unless this is an official released version.
If you really want to upgrade to a non-release version, you can set
database-upgrade=truein your configuration file, or start
--database-upgrade=true(or set to false to never allow a non-reversible upgrade!)
Updated 8 months ago