On Sat, 2019-10-12 at 21:03 +0200, Pierre Malard wrote: > Ok, thanks. it’s now very clear… > I must stay in CentOS 7 as long as possible… > No, that's not the way to look at it. Yes, an upgrade of major CentOS versions is a wipe and re-install (unless you really, really know what you are doing), but the longevity of the OS is usually greater than the lifetime of the hardware so there is no *urgency* to upgrade, CentOS 7 is not going to go away for a few years. The sensible way (i.e. what I do!), is to play with the new version for a little while, testing critical infrastructure and getting a feel for how it all works both standalone and with the rest of my estate. During that process I get to grips with installation procedures, PXE, kickstart, creating my bespoke RPMs and so on. Eventually, by probably 8.1 I will be deploying it for non mission-critical servers. Only then will I think about re-deploying current applications on to CentOS 8 and the urgency with which that is done is governed by the need for the newer versions of applications. But I will still be deploying CentOS 7 on new hardware for a while, but with the knowledge that the OS will still outlast the machines. P.