debsums is a useful utility to validate packages in a ubuntu or debian system.


sudo debsums -c

If this identifies any problems you can fix them using.:

sudo apt install --reinstall <package name>

If debsums idenfifies several packages with issues, to fix all of them use:

sudo apt install --reinstall $(dpkg -S $(debsums -c) | cut -d : -f 1 | sort -u)

For more information there is a useful post about debsums on askubuntu

Upgrade to 20.04



If 20.04.1 is still not released when you run this command, then you can upgrade using do-release-upgrade -d.


Just so you remember, an additional SSH daemon will be started at port ‘1022’.

  • Select the recommended option for the LXD snap track i.e. version 4.0

This message was displayed at the end of the upgrade:


I clicked Yes to continue, and all was well.


Uninstall Salt (Master and Minion)…


# /etc/apt/sources.list.d/saltstack.list:
deb http://repo.saltstack.com/py3/ubuntu/20.04/amd64/latest focal main

Re-install Salt

Postgres Upgrade Cluster

To move the data from Postgres 10 to 12, run the following as root:

# list the clusters

# drop the new (empty) cluster
pg_dropcluster 12 main --stop
# migrate the data from 10 to 12
pg_upgradecluster 10 main

# remove the 10 cluster
pg_dropcluster 10 main --stop

# remove the old database engine
apt remove postgresql-10

# list the clusters
Ver Cluster Port Status Owner    Data directory              Log file
10  main    5432 online postgres /var/lib/postgresql/10/main /var/log/postgresql/postgresql-10-main.log

For more information, see Postgres Upgrade Cluster


For Ubuntu 20.04, we are using the certbot package:

rm -rf /opt/letsencrypt

For more information, see the diff: Use ‘certbot’ package (rather than letsencrypt git repo)