Fully update Ubuntu system
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<yambe:breadcrumb>Ubuntu|Ubuntu</yambe:breadcrumb>
Fully update ubuntu system
To fully update an Ubuntu system connected to Internet use:
apt-get update apt-get upgrade -f apt-get dist-upgrade -f
Note that "apt-get upgrade" only installs new packages of available versions. -f is for installing missing dependencies. upgrade does not removes installed packages.
Whereas "apt-get dist-upgrade" can also remove packages to smartly upgrade. This is necessary to update packages such as kernels which typically require removal of some older packages. This wont update the OS release. For example this wont change from 16.04LTS to 16.10 non-LTS. This will only install packages available for that particular release.
If you also want to update release then use:
sudo do-release-upgrade
Refer: