Update the resource update.
sudo apt-get update
The software upgrade.
sudo apt-get upgrade
Then install the system update, if you do not want to upgrade the system version, complete this step on it.
sudo apt-get dist-upgrade
Reboot the system after installing the above update.
sudo reboot
Detect whether there is a new version of ubuntu.
sudo apt-get update
sudo update-manager -c -d
If there is still need to upgrade the software, select all, then " Install Now ", then "OK."
Then we can re-use update-manager detects pop-up window click on the " upgrade ", you can step through the upgrade of the system.
sudo update-manager -c -d
-------------------
Reprint:
https://jingyan.baidu.com/article/359911f5ad774057fe030684.html
https://jingyan.baidu.com/article/359911f5ad774057fe030684.html