Some information of Debian systems ================================== This document describes some configuration customizations and other sysadmin tasks I do when I set up a Debian host. Debian post-installation commands --------------------------------- ``dpkg-reconfigure locales`` Reconfigure locales, for example to ``en_US en_US.UTF-8 fr_FR.UTF-8 fr_FR@euro``. Keep in mind SSH preserve locale across the connection so a single UTF-8 locale is not enough. ``dpkg-reconfigure console-data && dpkg-reconfigure keyboard-configuration`` Change which keyboard configuration to use. ``loadkeys`` can also be used, with keymaps in ``/usr/share/kbd/keymaps``. After this: ``service keyboard-setup restart``. ``cd /usr/bin && sudo ln -s python python2`` For scripts which require python2 command. ``update-rc.d $SERVICE remove`` or ``sysv-rc-conf`` Remove some unneeded services from boot. Opposite operation is ``defaults``. Enable persistent iptables configuration: .. code-block:: sh apt-get install iptables-persistent systemctl enable netfilter-persistent.service Or persistent nftables configuration: .. code-block:: sh systemctl enable nftables.service APT configuration ----------------- This configuration doesn't install recommended packages by default. ``/etc/apt/apt.conf``:: APT::Install-Recommends "0"; APT::Install-Suggests "0"; To configure an HTTP proxy, you need to add one more line:: Acquire::http::Proxy "http://proxy.example.com:8080/"; ``/etc/apt/sources.list`` file depends on your location:: # Here is this file for a Debian Unstable in the US. deb http://http.us.debian.org/debian/ sid main contrib non-free deb-src http://http.us.debian.org/debian/ sid main contrib non-free # And here for a Debian Squeeze server in Germany deb http://ftp.de.debian.org/debian squeeze main contrib non-free deb http://ftp.de.debian.org/debian-security squeeze/updates main contrib non-free You may install ``debsums`` package to check the integrity of the installed files. There is a cron job with ``debsums`` which is configured by ``/etc/default/debsums``:: # Set this to never to disable the checksum verification or # one of "daily", "weekly", "monthly" to enable it CRON_CHECK=never Apticron is a program which automatically downloads the new updates (without installing them) and send mails about them. By default, it is configured to run every day. To change this to a weekly-based period, you need to edit ``/etc/cron.d/apticron``:: # Sunday, 0:41 41 0 * * 0 root if test -x /usr/sbin/apticron; then /usr/sbin/apticron --cron; else true; fi Apache commands --------------- ``a2dismod status`` Disable the status module. ``a2dissite default`` Disable the default site, you need to write your own site file and enable it. Postfix configuration --------------------- To send system messages by email, it is a good idea to have a mail server on an host which is configured as an "Internet Site". On a Debian host Postfix seems to be a good choice and is easy to install, configure and manage. Reload aliases after any change in ``/etc/aliases``:: postaliases /etc/aliases || newaliases postfix reload ``/etc/aliases`` example:: root: root@example.com postmaster: root abuse: root user: root web: web@example.com www: web The name of the mail system is written down in ``/etc/mailname``.