eQmail doesn't have a different install process than (net)qmail. Nevertheless there were be used some values:
 /var/qmail 
, since eQmail-1.10  /var/local/qmail 
 foo 
Replace these values with yours if necessary. It is recommended to use the user mechanism of qmail always, even if an equivalent system user exists.
Download sources and extract it:
$> wget https://github.com/kp-org/eQmail/archive/1.09-RC1.tar.gz $> tar -xvzf eqmail-1.09.tar.gz -C /usr/src $> cd /usr/src/eqmail-1.09
Edit the conf-* files to your needs. Each of these files has a description in it. The file  conf-qmail 
defines the home directory (default: /var/qmail).
Create the necessary users - optional use the script  mkusers 
to do this. If the script fails, it have to be done by hand. As example on a typical linux system do:
$> groupadd nofiles $> useradd -g nofiles -d /var/qmail/alias alias $> useradd -g nofiles -d /var/qmail qmaild $> useradd -g nofiles -d /var/qmail qmaill $> useradd -g nofiles -d /var/qmail qmailp $> groupadd qmail $> useradd -g qmail -d /var/qmail qmailq $> useradd -g qmail -d /var/qmail qmailr $> useradd -g qmail -d /var/qmail qmails
These are the default users and groups. They are configured in  conf-users 
and  conf-groups  
. These names have to match with the created ones. The  mkusers 
script uses the values from the conf files.
The qmail users and groups have to exists, otherwise eQmail will not compile!
Build and do basic configuration:
$> make $> make setup check $> ./config-fast <fqdn>
The  <fqdn> 
parameter is optional. If not given it will be tried to get the fqdn from  hostname -f  
.
Caveat: the alternative tool  config 
may not work properly always. It is still the same as in (net)qmail. This will be changed in a later version of eQmail.
Now you should have anything in the qmail home directory. The subfolder  control 
contains the config files:
To make sure they have valid values, check at least the first four of these files.
Create the recommended system aliases:
$> cd /var/qmail/alias $> echo foo > .qmail-root $> echo root > .qmail-postmaster $> ln -s .qmail-postmaster .qmail-mailer-daemon $> ln -s .qmail-postmaster .qmail-abuse $> chmod 644 .*
By using qmail users create the qmail user foo. The used ID's 65534:65533 are nobody and nogroup:
$> cd /var/qmail/users $> cat > assign <<EOF =foo:foo:65534:65533:/var/qmail/users/foo::: . EOF $> ../bin/qmail-newu $> mkdir foo $> ../bin/maildirmake foo/.Maildir $> chown -R 65534:65533 foo
There are several ways to do this. The most common method is to use uscpi-tcp and daemontools. There is a lot of documentation out which describes how to do this. eQmail doesn't differ on such a setup from (net)qmail. A good starting point is LWQ.
Alternative xinetd can be used. There are at least to points to prefer it:
First we create the startup script for qmail-start. In the example below the start-stop-daemon will be used. The benefit is that a pidfile will be created and the service will run in the background. Create a file (e.g.  /etc/{rc.d,init.d}/eqmaild  
):
#!/bin/sh conf() { DAEMON="qmail-send" pidfile="/var/run/qmail.pid" logger="/var/qmail/bin/splogger" } start() { conf echo "Starting eQmail: ${DAEMON}" start-stop-daemon --quiet --start --pidfile "${pidfile}" -m --background \ --exec env - PATH="/var/qmail/bin:$PATH" \ qmail-start "`cat /var/qmail/control/defaultdelivery`" ${logger} qmail # eend $? } stop() { conf echo "Stopping eQmail: ${DAEMON}" start-stop-daemon --quiet --stop --pidfile "${pidfile}" # eend $? }
This could be an example only. Refer to the system documentation how to run a service at boot time.
Now we have to make listen the smtp daemon on a network port. Create a config file for xinetd, e.g.  /etc/xinetd.d/smtp-service  
:
service smtp { disable = no id = smtp flags = NAMEINARGS IPv4 socket_type = stream protocol = tcp wait = no user = qmaild group = qmail interface = 0.0.0.0 only_from = 0.0.0.0 instances = UNLIMITED log_type = SYSLOG mail server = /var/qmail/bin/tcp-env server_args = -R /var/qmail/boot/qmail-xinetd env = RELAYCLIENT= }
The option server args contains the “run” file which will be invoked to start  qmail-smtpd 
. It calls here  /var/qmail/boot/qmail-xinetd 
and looks like:
exec 3>&1 /var/qmail/bin/qmail-smtpd /var/qmail/qmail-pwrap 2>&1 1>&3 3>&- | /var/qmail/bin/splogger xinetd-smtpd 2 3>&- exec 3>&-
The redirections of the file descriptor are necessary with xinetd - beware of it.
Now execute  eqmaild 
and  xinetd 
. Test if all works fine with:
$ telnet localhost 25 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 220 <hostname> ESMTP quit $
and
$ echo to: foo | /var/qmail/bin/qmail-inject $