Em man dpkg
--configure package...|-a|--pending
Configure a package which has been unpacked but not yet config‐
ured. If -a or --pending is given instead of package, all
unpacked but unconfigured packages are configured.
Configuring consists of the following steps:
1. Unpack the conffiles, and at the same time back up the old
conffiles, so that they can be restored if something goes wrong.
2. Run postinst script, if provided by the package.
Em man dpkg-reconfigure
dpkg-reconfigure - reconfigure an already installed package
-pvalue, --priority=value
Specify the minimum priority of question that will be displayed.
dpkg-reconfigure normally shows low priority questions no matter
what your default priority is. See debconf(7) for a list.
-a, --all
Reconfigure all installed packages that use debconf. Warning: this
may take a long time.
Aqui dpkg --configure -a configurará todos os pacotes descompactados, mas não configurados. Considerando que dpkg-reconfigure -phigh -a irá reconfigurar todos os pacotes instalados que usam debconf com alta prioridade.