Today I was told one of our server has been attacked through SSH, so I asked my friend, if there are any tools I can use? he recommended DenyHosts.

DenyHosts is an open source script intended to be run by Linux system administrators to help thwart SSH server attacks (also known as dictionary based attacks and brute force attacks).
If you’ve ever looked at your ssh log (/var/log/secure on Redhat, /var/log/auth.log on Mandrake, etc…) you may be alarmed to see how many hackers attempted to gain access to your server. Hopefully, none of them were successful (but then again, how would you know?). Wouldn’t it be better to automatically prevent that attacker from continuing to gain entry into your system?
You can Download the latest version of DenyHosts here.

I am still looking for a better solution for our email marketing business, and OpenEMM is one of application I have tested.

OpenEMM is a feature-rich enterprise software for email marketing, newsletters and service mails (transaction mails and event or time triggered mails). OpenEMM offers bounce management, link tracking, lots of realtime statistics and a scripting feature.

Environment,
Host: CentOS4.6_x86_64
virtualization software: OpenVZ
Guest:centos-5-i386-default-5.3-20090330

Because OpenEMM only have i386 release, so I have to create i386 VPS under CentOS4.6_x86_64
Download template:
#wget http://download.openvz.org/template/precreated/contrib/centos-5-i386-default-5.3-20090330.tar.gz
Create VE:
#vzctl create 101 –ostemplate centos-5-i386-default-5.3-20090330 –config vps.basic
other settings, please visit Create My First VE under OpenVZ

Install necessary software and do prepare job:
#yum install mysql-server sendmail-cf MySQL-python
#groupadd openemm
#useradd -m -g openemm -d /home/openemm -c “OpenEMM 5.5.1″ openemm

Download jdk-1_5_0_17-linux-i586.bin:
#chmod +x jdk-1_5_0_17-linux-i586.bin
#./jdk-1_5_0_17-linux-i586.bin
#mkdir -p /opt/openemm.org/software
#mv ./jdk1.5.0_17 /usr/
#ln -s /usr/jdk1.5.0_17 /opt/openemm.org/software/java
Test the JDK:
#/opt/openemm.org/software/java/bin/java -version

#wget http://nchc.dl.sourceforge.net/sourceforge/openemm/OpenEMM-5.5.1-1.i386.rpm
rpm -ihv OpenEMM-5.5.1-1.i386.rpm
mysql openemm

Start OpenEMM
(run as superuser)
Become the user ’openemm’ by running
#su – openemm
Change to the directory containing the startup/shutdown script.
#cd bin
To start the OpenEMM enviroment, run
#nohup OpenEMM.sh start &
To stop OpenEMM
#OpenEMM.sh stop

In order to save time and easily clone, backup and restore OpenVZ VE under CentOS4.6_x86_64, I found a tool named vzdump, it is very easy to use.

Install vzdump
#wget http://download.openvz.org/contrib/utils/vzdump/vzdump-1.0-2.noarch.rpm
#rpm -i vzdump-1.1-1.noarch.rpm
#yum install rsync
I also need
#wget http://dag.wieers.com/rpm/packages/cstream/cstream-2.7.4-3.el4.rf.x86_64.rpm
#rpm -i cstream-2.7.4-3.el4.rf.x86_64.rpm

Backup my first VE,
vzdump --compress --stop 101
it will create two file under /vz/dump folder, vzdump-101.tgz and vzdump-101.log

Restore
to do restore job, first I destroy VE 101
#vzctl stop 101
#vzctl destroy 101
then restore 101
vzdump –restore /vz/dump/vzdump-101.tgz 101

Clone
vzdump –restore /vz/dump/vzdump-101.tgz 102
clone is similar with restore but with a different veid
then do some set up job similar with create a new ve.