Preinstallation tasks

Changelog

• Jan 21, 2026
  - added notes for Alma Linux
• Jan 5, 2026
- qmail now avoids the PCRE dependency to make happy Debian 13 users

Before we start let's see how to prepare our machine for the installation. What follows is mostly a collection of hints that I extracted from the comments, so feel free to contribute.

On Debian 13, you may have to install at least these packages:

apt install build-essential autoconf automake libmariadb-dev default-libmysqlclient-dev libidn2-dev

You can decide to install a wider set of packages, if your installation doesn't provide the webserver and the database:

apt install sudo git autoconf automake build-essential libssl-dev \
libmariadb-dev default-libmysqlclient-dev mariadb-server pkg-config \
libev-dev unzip help2man net-tools apache2 python-dev-is-python3 fcgiwrap \
apache2-utils libnet-ssleay-perl php php-fpm php-zip libidn2-dev libbz2-dev liblz4-dev

This is the list of packages to install on Ubuntu 22.04:

apt install build-essential autoconf automake libmariadb-dev libmariadb-dev-compat \
wget man help2man unzip psmisc libexpat-dev libidn2-dev libbz2-dev pkg-config

This is the required packages on Alma Linux v. 9.7, which could be the same on other RedHat-like systems:

dnf groupinstall "Development Tools" -y 
dnf install -y openldap openldap-devel openldap-clients bzip2-devel \
lz4-libs lz4-devel rpcgen expat-devel libidn2-devel perl-diagnostics \
mariadb-server mariadb-devel

Since we are going to install a couple of packages in /usr/local, you have to add it to your ld.so.conf:

cat >> /etc/ld.so.conf.d/usr-local.conf << __EOF__
/usr/local/lib
/usr/local/lib64
/usr/local/qlibs
__EOF__

rc.local or systemd?

Maybe you are wondering if it is convenient to let systemd handle the boot of the daemontools, dovecot, spamassassin and so on. I strongly advise against using systemd, especially for daemontools to start/stop them by means of dedicated scripts (qmailctl for instance). Keep in mind that, if you let systemd manage daemontools and the other programs, you will not be able to use other control scripts like qmailctl and dovecotctl to manage the start and stop of services and that you will diverge from what is reported here. Therefore, expecially if you are a newby, I suggest to strictly follow this guide. The comments on this blog have many requests for help from users who have systemd supervising everything and then use qmailctl boot/stop/start causing overlaps and processes that fail due to the inability to acquire the supervise/lock files.

Installing rc.local as a systemd service

In the following guide, our services (not only qmail) will be launched at boot time via rc.local, which is dismissed on a systemd OS. So let's create a new rc.local executable and define it as a systemd service.

Create rc.local and make it executable:

cat > /etc/rc.local << __EOF__ 
#!/bin/bash -e 

__EOF__
chmod +x /etc/rc.local

Create the systemd service:

cat > /etc/systemd/system/rc-local.service << __EOF__ 
[Unit] 
Description=/etc/rc.local 
ConditionPathExists=/etc/rc.local 

[Service] 
Type=forking 
ExecStart=/etc/rc.local 
TimeoutSec=0 
StandardOutput=tty 
RemainAfterExit=yes 

[Install] 
WantedBy=multi-user.target 
__EOF__

Enable and start:

systemctl enable rc-local 
systemctl start  rc-local

Check your IP's reputation

When you buy an IP address, you know that it's not new and you inherit its reputation. So the first thing you may want to do is to check if it's listed in some RBL here: http://multirbl.valli.org or https://mxtoolbox.com/SuperTool.aspx

I think it would convenient for anyone to have a list of tools to remove an IP from the blocklists around the world. Please contribute posting a comment below. Here is the first one:

• https://ipremoval.sms.symantec.com for blocklist which uses Symantec

helodnscheck.cpp:106:10: fatal error: pcre.h: No existe el fichero o el directorio 
 106 | #include  
     |          ^~~~~~~~ 
compilation terminated.

root@sa:~/scripts# cat /etc/issue 
Debian GNU/Linux 12 \n \l

root@sa:~/scripts# apt list | grep libpcre 
libpcre2-16-0/stable 10.42-1 amd64 
libpcre2-32-0/stable 10.42-1 amd64 
libpcre2-8-0/stable,now 10.42-1 amd64 
libpcre2-dev/stable 10.42-1 amd64 
libpcre2-posix3/stable 10.42-1 amd64 
libpcre3-dbg/stable 2:8.39-15 amd64 
libpcre3-dev/stable 2:8.39-15 amd64 

helodnscheck: helodnscheck.cpp 
       c++ -o helodnscheck helodnscheck.cpp -lpcre \ 
       -I/usr/local/include -I/usr/pkg/include \ 
       -L/usr/local/lib -L/usr/pkg/lib

cat -vet filename