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Question

What's the difference between:

sudo /etc/init.d/apache2 restart

and

sudo service apache2 restart

I tried the first one, and it didn't apply my changes, while

sudo service apache2 restart

did uptake my changes.

Answer 1

Here is what is actually happening when you run sudo /etc/init.d/apache2 restart :

if ! $APACHE2CTL configtest > /dev/null 2>&1; then
    $APACHE2CTL configtest || true
    log_end_msg 1
    exit 1
fi
if check_htcacheclean ; then
        log_daemon_msg "Restarting web server" "htcacheclean"
        stop_htcacheclean
        log_progress_msg apache2
else
        log_daemon_msg "Restarting web server" "apache2"
fi
PID=$(pidof_apache) || true
if ! apache_wait_stop; then
        log_end_msg 1 || true
fi
if $APACHE2CTL start; then
        if check_htcacheclean ; then
                start_htcacheclean || log_end_msg 1
        fi
        log_end_msg 0
else
        log_end_msg 1
fi

As you can see; first a config test is run, if this is successful the server is stopped and then started.

I find it hard to believe that running this command did not apply your changes if they were properly saved and valid. I only use this command and have never had that issue.

/usr/bin/service is described as:

# A convenient wrapper for the /etc/init.d init scripts.

And it does the following:

SERVICEDIR="/etc/init.d"

# Otherwise, use the traditional sysvinit
if [ -x "${SERVICEDIR}/${SERVICE}" ]; then
   exec env -i LANG="$LANG" PATH="$PATH" TERM="$TERM" "$SERVICEDIR/$SERVICE" ${ACTION} ${OPTIONS}
else
   echo "${SERVICE}: unrecognized service" >&2
   exit 1
fi

So the commands are basically identical, sudo service apache2 restart is just a wrapper for sudo /etc/init.d/apache2 restart .

You may also use sudo /etc/init.d/apache2 reload , this reloads the config without restarting the server. This only works if you have changed config, it will not load modules that you have enabled, for that you need to restart Apache.

Edit: This code is from a Debian system.

Answer 2

In general, whether these two commands are identical or not depends on your Linux distribution.

The first one requires the existence of a traditional SysV-style init script. Until a few years ago that was practically the only way to control services and the service script was just a simple wrapper that basically added the init script path.

These days many Linux distributions have switched to alternative service management systems such as upstart or systemd . Therefore, the service wrapper may also make use of these systems, providing a certain degree of compatibility.

Bottom line: depending on the specifics of your Linux distribution, the /etc/init.d/apache2 may not exist at all, it may just use service itself, or it may do nothing at all. My Mageia Linix system, for example, launches Apache using a systemd service file and has no SysV init script at all for it.

You are generally better off just using service <service> <command>... .