Problem Description:
ubuntu LTS long-term support version is not supported in the past period, the source is not apt to provide support. So we need to upgrade to the corresponding version of LTS
problem solved:
lab environment:
ubuntu17.10--->ubuntu18.04.3
01, view the current release
cat /etc/*release
02, perform the upgrade
Note: Removing the low version of apt sources apt to replace the source ubuntu18.04
apt update // update the target system apt source of local cache
apt list --upgradable // view there is a need to upgrade packages
apt -y upgrade // upgrade an existing system software package
apt dist-upgrade -y // upgrade system release
Note: The upgrade process requires manual confirmation
