Thomas Weise (汤卫思)

A professor at Hefei University.

2 minute read

I use for my work and try to keep my system up-to-date. This means that, whenever I shut down my computer, I run a little Here I post a small script update.sh that updates all installed packages, both deb and snap packages. Sometimes, for whatever reason, there may be a problem with some inconsistent package state. My script basically applies all methods I know to fix such state. The script is very heavy-handed and loops over the update process four times. If for whatever reason one update would require another first and that could only be done by multiple updates, then that’s no problem. I usually run something like sudo update.sh && shutdown now, which then shuts down my computer. So I do not really need to care how long the script needs anyway.

#!/bin/bash

# Fail on error.
set -o pipefail  # trace ERR through pipes
set -o errtrace  # trace ERR through 'time command' and other functions
set -o nounset   # set -u : exit the script if you try to use an uninitialized variable
set -o errexit   # set -e : exit the script if any statement returns a non-true return value

echo "$(date +'%0Y-%0m-%0d %0R:%0S'): The update script has started."

cd /tmp/  # Just to be on the save side.

echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Clearing caches and locks by force."
sudo rm -rf "/var/lib/apt/lists/lock" || true
sudo rm -rf "/var/cache/apt/archives/lock" || true
sudo rm -rf "/var/lib/dpkg/lock" || true

# updating the system
for i in {1..4}; do
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Now doing apt-get updates in run ${i}."
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Cleaning caches (1)."
    sudo apt-get -y clean
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Cleaning caches (2)."
    sudo apt-get -y autoclean
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Automatically remove packages that were installed to satisfy dependencies but are no longer needed (and deleting their configuration)."
    sudo apt-get -y autoremove --purge
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Deleting configurations no longer needed."
    sudo apt-get -y purge
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Getting current list of available packages."
    sudo apt-get -y update
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Getting current list of available packages, ignoring broken or missing packages."
    sudo apt-get -y update --fix-missing
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Resume and complete the configuration of packages that were unpacked but not fully configured, if any."
    sudo dpkg --configure -a
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Try to install missing dependencies or broken packages (1)."
    sudo apt-get -y --fix-missing install
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Try to install missing dependencies or broken packages (2)."
    sudo apt-get -y -f install
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Updating installed packages, installing new packages if needed."
    sudo apt-get -y --with-new-pkgs upgrade
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Verify that there are no broken dependencies."
    sudo apt-get -y check
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Try to install missing broken dependencies."
    sudo apt -y --fix-broken install
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Finished doing apt-get updates in run ${i}, now doing snap updates."
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Refreshing snaps (1)."
    sudo snap refresh
    sleep 1
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Terminating any snap store process that may prevent us from refreshing."
    sudo killall snap-store || true
    sleep 5
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Refreshing snaps (2)."
    sudo snap refresh
    echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Finished doing run ${i}."
    sleep 10
done

echo "$(date +'%0Y-%0m-%0d %0R:%0S'): Done updating."

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