Now and then you may notice that apt-get upgrade command keeps a few packages back, meaning they don’t get upgraded. This quick post shows what you can do about it and how to get all the packages upgraded.
How apt-get Keeps Packages Back
This is how keeping packages back will look like:
Why Packages Are Kept Back by apt-get
Most likely reason for keeping packages back is that upgrading them means installing new packages or removing existing ones. apt-get upgrade strictly upgrades existing packages, without removing or installing anything.
Since the command you’re giving to apt-get is upgrade and not to install new packages, packages that require some old packages removed or new packages installed are kept back.
How To Upgrade Packages That Were Kept Back
Simply use the dist-upgrade option of apt-get, which will resolve dependencies and install/remove dependent package as needed: