==== VirtualBox for CentOS 7 to CentOS 8 Upgrade in Place ====

Notes for upgrading CentOS7 to CentOS8 in place:

https://www.alessandronuccio.it/2020/10/21/upgrade-centos-7-to-centos-8/

  * 'rpm -e `rpm -q kernel`' would fail, try to erase current kernel
  * 'dnf --releasever=8 --allowerasing --setopt=deltarpm=false distro-sync' would also fail, trying to remove the current kernel
  * Got stuck into kernel dependency issues
  * Aborted this track

https://www.centlinux.com/2020/01/how-to-upgrade-centos-7-to-8-server.html

  * Had to follow instructions very carefully and ensure to follow every step
  * Finally got to a point I could not continue


Tried this but failed:

dnf upgrade http://mirror.centos.org/centos/8/BaseOS/x86_64/os/Packages/{centos-release-8.1-1.1911.0.8.el8.x86_64.rpm,centos-gpg-keys-8.1-1.1911.0.8.el8.noarch.rpm,centos-repos-8.1-1.1911.0.8.el8.x86_64.rpm}

Then tried this:

dnf upgrade http://mirror.centos.org/centos/8/BaseOS/x86_64/os/Packages/{centos-linux-release-8.3-1.2011.el8.noarch.rpm,centos-gpg-keys-8-2.el8.noarch.rpm,centos-linux-repos-8-2.el8.noarch.rpm}

Package centos-linux-release not installed, cannot update it.

No match for argument: /var/cache/dnf/commandline-5fda33494c9fb882/packages/centos-linux-release-8.3-1.2011.el8.noarch.rpm
Package centos-gpg-keys not installed, cannot update it.
No match for argument: /var/cache/dnf/commandline-5fda33494c9fb882/packages/centos-gpg-keys-8-2.el8.noarch.rpm
Package centos-linux-repos not installed, cannot update it.
No match for argument: /var/cache/dnf/commandline-5fda33494c9fb882/packages/centos-linux-repos-8-2.el8.noarch.rpm
Error: No packages marked for upgrade.

Then did this:

dnf install http://mirror.centos.org/centos/8/BaseOS/x86_64/os/Packages/{centos-linux-release-8.3-1.2011.el8.noarch.rpm,centos-gpg-keys-8-2.el8.noarch.rpm,centos-linux-repos-8-2.el8.noarch.rpm}

Seemed to work.

Ran dnf --releasever=8 --allowerasing --setopt=deltarpm=false distro-sync

but got this:

Error: transaction check vs depsolve:
(gcc >= 8 with gcc < 9) is needed by annobin-9.23-1.el8.x86_64
rpmlib(RichDependencies) <= 4.12.0-1 is needed by annobin-9.23-1.el8.x86_64
(mariadb >= 3:10.3.27 if mariadb) is needed by mariadb-connector-c-3.1.11-2.el8_3.x86_64
(mariadb-connector-c-config = 3.1.11-2.el8_3 if mariadb-connector-c-config) is needed by mariadb-connector-c-3.1.11-2.el8_3.x86_64
rpmlib(RichDependencies) <= 4.12.0-1 is needed by mariadb-connector-c-3.1.11-2.el8_3.x86_64
(mariadb-devel >= 3:10.3.27 if mariadb-devel) is needed by mariadb-connector-c-devel-3.1.11-2.el8_3.x86_64
rpmlib(RichDependencies) <= 4.12.0-1 is needed by mariadb-connector-c-devel-3.1.11-2.el8_3.x86_64
(lightdm-greeter = 1.2 if xorg-x11-server-Xorg) is needed by lightdm-1.30.0-6.el8.x86_64
rpmlib(RichDependencies) <= 4.12.0-1 is needed by lightdm-1.30.0-6.el8.x86_64
(flatpak-selinux = 1.6.2-6.el8_3 if selinux-policy-targeted) is needed by flatpak-1.6.2-6.el8_3.x86_64
rpmlib(RichDependencies) <= 4.12.0-1 is needed by flatpak-1.6.2-6.el8_3.x86_64
(annobin if gcc) is needed by redhat-rpm-config-123-1.el8.noarch
rpmlib(RichDependencies) <= 4.12.0-1 is needed by redhat-rpm-config-123-1.el8.noarch
To diagnose the problem, try running: 'rpm -Va --nofiles --nodigest'.
You probably have corrupted RPMDB, running 'rpm --rebuilddb' might fix the issue.
The downloaded packages were saved in cache until the next successful transaction.
You can remove cached packages by executing 'dnf clean packages'.

Ran: dnf remove vdo fcoe-utils

rpm -Va --nofiles --nodigest

rpm --rebuilddb

Can't continue.