System upgrade commands for Debian/ubuntu and CentOS

Prior to installing/configuring the system production environment, it is generally necessary to upgrade the existing system to ensure that the packages/components within the system are up to date, and that the upgrade commands for Debian/ubuntu and CentOS are different, as follows:

Debian/ubuntu, enter:

Apt-get Update

When the system is finished, enter:

Apt-get Upgrade

Wait for system operation to complete. This step, if you do not consider the dependencies between components within the system, and then upgrade them, change them to:

Apt-get Dist-upgrade

Wait for system operation to complete.

The difference between the specific Apt-get upgrade and the Apt-get Dist-upgrade is as follows:

Under the same system version, the Apt-get upgrade will only upgrade the package that satisfies the current dependency in the real system, without adding a reduction, and the difference between Apt-get Dist-upgrade is to fix the dependency on the dependencies and then upgrade That is, Apt-get Dist-upgrade will install or remove the necessary packages to satisfy the dependencies so that the packages that can be upgraded are upgraded. Under normal circumstances, Apt-get upgrade is sufficient.

CentOS, enter:

Yum Update

Wait for system operation to complete.