__________

Linux command and other help

__________

Fedora Core 2 installation.

(for DNS server)

__________

Fedora Core 4 installation.

(for DNS server)

__________

Net-Qmail Installation Powerful Linux E-mail Server

_________

To install webmin in fedora core 3

__________

INSTALLATION OF MRTG & RRD TOOL (Fedora Core2/ Redhat 8/ 9)

__________

Squid Installation.

__________

Another Squid installation

_________

Apache Installation

__________

ISP Servers IPtables firewall setup

__________

Linux Monitoring system Setup

_________

Linux Base POP/ POP3 and SMTP traffic Virus and Spam Scanning/ filtering Firewall

_________

Clam Anti Virus Installation

_________

Spam-Assassin Installation

_________

Bonding / Binding Multiple interfaces into single interface

_________

Use more than 1 DSL modems without noticing disconnectivity

_________

rrizwanahmed@gmail.com

All configuration are working fine in live/ LAB environments

Installing ClamAV

With the help of http://tldp.org/HOWTO/html_single/Qmail-ClamAV-HOWTO/#AEN114

Download the ClamAV source at http://www.clamav.net. Use ClamAV’s latest version.

#tar -xvzf clamav-0.65.tar.gz

#cd clamav-0.65 #groupadd clamav

#useradd clamav -g clamav -c "Clam AntiVirus" -s /nonexistent .

#/configure

#make

#make install

#cd ..

Testing

As long as make and make install have finished without errors, you are now ready to test your installation (If you did experience errors, please review the ClamAV documentation that was included in the tar ball. You may also try the ClamAV website for some helpful tips). To test your installation type:

#clamscan -r -l scan.txt clamav-0.65

Clamscan should find a test virus (This is NOT a real virus) in the clamav-0.65/test directory and log it to the scan.txt log file.

Now you need to configure the ClamAV daemon, clamd, for testing.

#vi /usr/local/etc/clamav.conf

Comment out "Example" line in clamav.conf and save.

#clamdscan -l scan.txt clamav-0.65

This should provide output that is similar to the clamscan command you entered above.

Updating Defs

Now we need to update our virus definitions. Clamscan includes a utility, freshclam, to take care of this. Freshclam automatically changes from root to the clamav user that you created during the installation. First, create a log file that freshclam can log to.

#touch /var/log/clam-update.log

#chmod 600 /var/log/clamupdate.log

#chown clamav /var/log/clamupdate.log

Now start freshclam:

#freshclam -d -c 6 -l /var/log/clam-update.log

This checks for a new virus definition database six (6) times a day. Check the /var/log/clam-update.log file. It should look something like this:

-----------------------------------------------------------------------------------------------------

ClamAV update process started at Wed Jan 28 17:49:48 2004

main.cvd is up to date (version: 19, sigs: 19987, f-level: 1, builder: ddm)

daily.cvd updated (version: 111, sigs: 597, f-level: 1, builder: tomek)

Database updated (20584 signatures) from database.clamav.net (81.4.91.185).

-----------------------------------------------------------------------------------------------------

Now add the freshclam -d -c 6 -l /var/log/clam-update.log to your startup scripts.

You can also setup a cronjob to update the Defs every 6 hours, if you like.

#vi /etc/crontab

0 6 * * * root /usr/local/bin/clamscan

Setting up Clamd and Using With Daemontools

Edit /etc/clamd.conf and make the following changes.

#vi /etc/clamd.conf

Uncomment "LogSyslog"

Uncomment "StreamSaveToDisk"

Uncomment "MaxThreads" and change value to "30"

Uncomment "User" and change value to "qscand"

Uncomment "Foreground"

Uncomment "ScanMail"

Create the clamav directory.

#mkdir -p /usr/local/clamav/bin

Now create a startup/shutdown script for clamd. Copy and paste the script shown below. This script was written by Jesse D. Guardiani.

#vi /usr/local/clamav/bin/clamdctl

#!/bin/sh

# For Red Hat chkconfig

# chkconfig: - 80 30

# description: the ClamAV clamd daemon

PATH=/usr/local/clamav/bin:/bin:/usr/bin:/usr/local/bin:/usr/local/sbin

export PATH

case "$1" in

  start)

    echo "Starting clamd"

    if svok /service/clamd ; then

      svc -u /service/clamd

    else

      echo clamd supervise not running

fi

    if [ -d /var/lock/subsys ]; then

      touch /var/lock/subsys/clamd

fi

;;

  stop)

    echo "Stopping clamd..."

    echo "  clamd"

    svc -d /service/clamd

    if [ -f /var/lock/subsys/clamd ]; then

      rm /var/lock/subsys/clamd

fi

;;

  stat)

    svstat /service/clamd

    svstat /service/clamd/log

;;

  restart)

    echo "Restarting clamd:"

    echo "* Stopping clamd."

    svc -d /service/clamd

    echo "* Sending clamd SIGTERM and restarting."

    svc -t /service/clamd

    echo "* Restarting clamd."

    svc -u /service/clamd

;;

  hup)

    echo "Sending HUP signal to clamd."

    svc -h /service/clamd

;;

  help)

    cat <<HELP

   stop -- stops clamd service (smtp connections refused, nothing goes out)

  start -- starts clamd service (smtp connection accepted, mail can go out)

   stat -- displays status of clamd service

restart -- stops and restarts the clamd service

    hup -- same as reload

HELP

;;

*)

    echo "Usage: $0 {start|stop|stat|restart|hup|help}"

    exit 1

;;

esac

exit 0

Make clamdctl an executable and link to path:

#chmod 755 /usr/local/clamav/bin/clamdctl

#chown clamav /usr/local/clamav/bin/clamdctl

#ln -s /usr/local/clamav/bin/clamdctl /usr/local/bin

Create the supervise directories for the clamd service:

#mkdir -p /usr/local/clamav/supervise/clamd/log

Now you must create the /usr/local/clamav/supervise/clamd/run file, or just copy and paste the script shown below. This script was also created by Jesse D. Guardiani:

vi /usr/local/clamav/supervise/clamd/run

#!/bin/sh

# --------------------------------------------------

# run

# Purpose     - Start the clamd daemon/service.

# Author      - Jesse D. Guardiani

# Created     - 09/10/03

# Modified    - 09/25/03

# --------------------------------------------------

# This script is designed to be run under DJB's

# daemontools package.

#  ChangeLog

#  ---------

#  09/25/03 - JDG

#  --------------

#  - Changed clamd user to qscand in compliance with

#    the change to qmail-scanner-1.20rc3

#  09/10/03 - JDG

#  --------------

#  - Created

# --------------------------------------------------

# Copyright (C) 2003 WingNET Internet Services

# Contact: Jesse D. Guardiani (jesse at wingnet dot net)

# --------------------------------------------------

lockfile="/tmp/clamd"   # Location of clamd lock file

path_to_clamd="/usr/local/sbin/clamd"

                        # Location of the clamd binary

BAD_EXIT_CODE=1         # The exit code we use to announce that something bad has happened

# The following pipeline is designed to return the pid of each

# clamd process currently running.

get_clam_pids_pipeline=`ps -ax | grep -E "${path_to_clamd}\$" | grep -v grep | awk '{print $1}'`

# --------------------------------------------------

# Generic helper functions

# --------------------------------------------------

# Basic return code error message function

die_rcode() {

        EXIT_CODE=$1

        ERROR_MSG=$2

        if [ $EXIT_CODE -ne '0' ]; then

               echo "$ERROR_MSG" 1>&2

               echo "Exiting!" 1>&2

               exit "$BAD_EXIT_CODE"

fi

# --------------------------------------------------

# 
Main

# --------------------------------------------------

ps_clamd=""

ps_clamd="$get_clam_pids_pipeline"

if [ -n "$ps_clamd" ]; then

        pid_count="0"

        for pid in $ps_clamd

do

               pid_count=`expr $pid_count + 1`

        done

        die_rcode $BAD_EXIT_CODE "Error: $pid_count clamd process(es) already running!"

fi

if [ -e "$lockfile" ]; then

        rm "$lockfile"

        exit_code="$?"

        die_rcode $exit_code "Error: 'rm $lockfile' call failed."

fi

exec /usr/local/bin/setuidgid qscand $path_to_clamd

# --

# END /usr/local/clamav/supervise/clamd/run file.

# --

Create the /usr/local/clamav/supervise/clamd/log/run file:

#vi /usr/local/clamav/supervise/clamd/log/run

#!/bin/sh

exec /usr/local/bin/setuidgid qscand /usr/local/bin/multilog t /var/log/clamd

Make the run files executable:

#chmod 755 /usr/local/clamav/supervise/clamd/run

#chmod 755 /usr/local/clamav/supervise/clamd/log/run

Now set up the log directories:

#mkdir -p /var/log/clamd

chown qscand /var/log/clamd

Finally, link the supervise directory into /service:

#ln -s /usr/local/clamav/supervise/clamd /service

* Note: The clamd script will start automatically shortly after these links are created. If you don't want it running, do the following:

#clamdctl stop

To start clamd backup, do the following

#clamdctl start

-------------Configuration Complete-------------