Hello Yann, I have no experience upgrading through several LTS versions. A mysql -> mariadb switch should not hurt. Anyway, be sure to backup the database, or even better snapshot the whole vm. When the os upgrade is ready, be sure to recompile Piler.
Be sure to stop all piler related processes even the ctontabs while upgrading the os. The other option could be to start a new vm with the choice of a recent distro with the latest master of Piler. Then export all emails from old server, and import to new one. This approach has the benefit of having everything new and up to date, however you need a lengthy import process. Janos On 10 Jan 2020, 09:18, at 09:18, Yann Lehmann <arist...@free-it.ch> wrote: > > >Hello Everyone > >Our Piler server is doing good so far (only service on a virtual >machine), but it is running on Ubuntu 14.04, which is no more >supported. > >I would like to either upgrade to Ubuntu 18.04 (actual LTS, or may be >wait some time and go to 20.04 the next LTS) or move to Debian 10. I >know that on Ubuntu, an in place upgrade is only possible from one LTS >version to the next, so in my case, it would be from 14.04 to 16.04, >and >then to 18.04. > > >I also know that if I upgrade from Ubuntu 14.04 to 16.04, I would have >to upgrade Mysql (or move to MariaDB) before the upgrade. > >What path would you advise: in place upgrade or move/reinstall on newer > >os ? And what were your experiences with in place upgrades on Ubuntu ? > >Thank's in advance for any advice and best regards >Yann