From 10.3 to 10.4 it shows an error:
Transaction Check Error:
file /usr/bin/garbd from install of galera-4-26.4.2-1.rhel6.el6.x86_64 conflicts with file from package galera-25.3.26-1.rhel6.el6.x86_64
galeria should be removed first!
Dependencies Resolved
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Package Arch Version Repository Size
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Removing:
galera x86_64 25.3.26-1.rhel6.el6 @mratwork-mariadb 37 M
Transaction Summary
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Remove 1 Package(s)
Installed size: 37 M
then MariaDB-server and galera-4 installs properly.