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On my ubuntu vps, I've this error, What does it mean? Why were packages kept back? I was advised not to do dist-upgrade. My question is not how to solve this, but why this happened?
The following packages have been kept back: mysql-client-5.5 mysql-server-5.5 mysql-server-core-5.5 0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.