yum update vs yum upgrade

Difference between yum update and yum upgrade

yum update -obsoletes = yum upgrade

If you run the command without any package, update will update every currently installed package.

If the -obsoletes flag is present yum will include package obsoletes in its calculations, this makes it better for distro-version changes

REMAKRS - This behaviour only applies when the obsolutes=0 is set in the yum.conf

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