The POSTUN script starts with:
if [ "$1" = "0" ] || [ "$1" = "remove" ]
so all actions in it will actually only be executed on real package removal, not up package upgrade, where $1 – the number of package installations by this name being active after the RPM transaction has finished – will be 1, not 0
So on yum update:
- no maxscale process restart, old version keeps running
- no update of /etc/logrotate.d/maxscale_logrotate (as this is copied over from /usr/share, and not directly contained in the package files maintained by rpm itself. This would actually be a problem by itself anyway, as if the POSTUN script actually worked any manual edits to the file would simply be lost, instead of being preserved by rpm in a .rpmold file)
- ... maybe more ...