update a system from CentOS 7 to CentOS 8?

[nehavilash]

How do I update a system from CentOS 7 to CentOS 8?
I've set up AAPanel and am currently hosting several websites on a CentOS 7 server with OVH Cloud. I'm looking to make the leap to CentOS 8 without risking any data loss. Considering the multiple websites running on the server, could someone provide guidance on how to achieve this upgrade safely?

[TrevorH]

Sorry to tell you but there is no CentOS 8. Red Hat abolished CentOS at the end of 2021 and CetnOS 8 is already dead. CentOS 7 limps on to its EOL in June this year and then there will be no supported CentOS versions.

There are two replacement distros that sprang up to take teh place that CentOS left: Alma and Rockyl Linux. Those both aim to be as close to RHEL as possible. There is a CentOS Stream 8 but it is a permanent beta product and unsuitable for production use and, in any case, that goes EOL about 3 weeks _before_ CentOS 7 so it's not a useful replacement in any way.

There has never been a supported upgrade from one version of CentOS to the next and it's not supported with Rocky or Alma either. In all cases the supported way to migrate from 7 to 8 is to install a parallel system and migrate your work over from one to the other. I'd also suggest skipping EL8 altogether as it was the Windows Vista of RHEL versions and is also about to enter its final maintenance phase (which lasts 5 years for RHEL 8).

[jlehtone]

I'm looking to make the leap to CentOS 8 without risking any data loss.

If you care about your data, then you already have backups.

There has never been a supported upgrade from one version of CentOS to the next and it's not supported with Rocky or Alma either. In all cases the supported way to migrate from 7 to 8 is to install a parallel system and migrate your work over from one to the other.

Fresh install (of parallel) is the logical solution. The config of the system has to be adapted no matter which distro you migrate to. Whether (user) data is easier to transfer from (live) old system or via backups is up to you.


The Alma project does have "ELevate", an adaptation of RHEL's leapp, but neither is certain to work, particularly when third-party content (which I assume the AAPanel to be) is present. You would still need to have backups at hand and be prepared to fall back to the "parallel install approach".