Free Linux Tutorials

Snort® is an open source network intrusion prevention and detection system (IDS/IPS) developed by Sourcefire.

Other definitions:
- Barnyard is an output system for Snort. Snort creates a special binary output format called unified. Barnyard reads this file, and then resends the data to a database backend. Unlike the database output plug-in, Barnyard manages the sending of events to the database and stores them when the database temporarily cannot accept connections.

-BASE is the Basic Analysis and Security Engine. It is based on the code from the Analysis Console for Intrusion Databases (ACID) project. This application provides a web front-end to query and analyze the alerts coming from a SNORT IDS system.

Relaying to Gmail via smtp.gmail.com can be accomplished by configuring your Postfix with SASL authentication and TLS encryption.

The common errors you will encounter if sending from your postfix mail server failing to gmail.com domain but works in other domains are:

@/var/log/maillog
-Must issue a STARTTLS command first
-certificate verification failed for gmail.com:unable to get local issuer certificate
-Authentication Required. Learn more at 530 5.5.1 http://mail.google.com/support/bin/answer.py?

How to fix?

Assuming you already installed Postfix and everything works fine except sending to gmail smtps, here are the steps to follow:

1. Configure Postfix main configuration

mysql-zrm is short for Zmanda Recovery Manager for MySQL. It lets you create full logical or raw backups of your databases , generate reports about the backups, verify the integrity of the backups, and recover your databases. It can also send email notifcations about the backup status, and you can implement multiple backup policies.

This procedure was successfully tested and implemented on CentOS 5.X and RHEL 5.X servers.
Pre-requisites:
1.mysql client, MySQL server 4.1 and above
2.perl-DBI and perl-XML-Parser
yum install perl-DBI perl-XML-Parser

Installation:

1.Download mysql-zrm on http://www.zmanda.com/download-zrm.php
2.Get the RPM
wget http://www.zmanda.com/downloads/community/ZRM-MySQL/2.1.1/RPM/MySQL-zrm-2.1.1-1.noarch.rpm
3.Install
rpm -ivh MySQL-zrm-2.1.1-1.noarch.rpm

1. Wonder why you can’t send email from your linux server?

2. Is your mail server or 3rd party email hosting provider requires authentication for your outgoing server to send out emails successfully?

3. Are you using a default sendmail email client on your linux box and wonder why your getting maillog errors such as this:

——-sample sendmail maillog error from my nagios server—————
Oct  2 17:03:54 nms sendmail[25657]: n9293qiw025655: to=<nagios@freelinuxtutorials.com>,

ctladdr=<root@nms.freelinuxtutorials.com> (0/0), dela0928, relay=smtp.freelinuxtutorials.com.

[216.200.145.17], dsn=5.1.1, stat=User unknown
Oct  2 17:03:54 nms sendmail[25657]: n9293qiw025655: n9293siw025657: DSN: User unknown
Oct  2 17:03:54 nms sendmail[25657]: n9293siw025657: to=<root@nms.freelinuxtutorials.com>,

I had the chance to work as a systems administrator in an e-commerce company and they have Linux dedicated servers leased/purchase from a hosting provider.
Dedicated servers compared to a shared hosting is you have full control of the box. You can do whatever you want with the box, implement services and of course a full root access with the machine.

With this company, we are hosting about 200+ websites and some of them are hosted in our  boxes run in Redhat Enterprise Linux. As part of administering the box is to have a full and incremental backup of our dynamic website files and database. Scheduled shell scripts are set on this machine and luckily, I was able to find one of the useful backup solution script that can be found in this site:

Step by Step Procedure

Step 1. Add 2 LAN cards to the Linux box. You need to have two(2) NICs, one for your private network and one for the public IP address

Step 2. Check if your networks cards are properly detected and installed. You can use the command “dmesg” to verify if it was recognized during the boot-up process

Sample output:
#dmesg |grep eth

e100: eth0: e100_probe: addr 0xfa061000, irq 177, MAC addr 00:10:DC:5E:A8:BF
e100: eth1: e100_probe: addr 0xfa060000, irq 185, MAC addr 00:10:DC:5E:A8:C0
e100: eth0: e100_watchdog: link up, 100Mbps, half-duplex
e100: eth1: e100_watchdog: link up, 100Mbps, full-duplex

* Setting up ftp via vsftpd in linux

The VSFTPD (Very Secure FTP Server Deamon) is one of the most commonly used FTP servers under Linux and comes with most Linux distributions.

This article will help you install and configure vsftpd in Linux. (sample OS used is a Red-hat based distribution)

GOALS:

* to create a secure ftp server
* to create an ftp user chrooted or jailed in a certain directory (sample use is an apache directory wherein you can limit users or your developers to just upload to a restricted folder)

The new release provides high level coverage of the improvements and additions that have been implemented in Red Hat Enterprise Linux 5.4.

Changes include:

a. Package Updates
b. New Packages
c. Technology Previews
d. Fix Known Issues
e. Package Manifest

Some important Updates are:

1. Virtualization Updates
2. Clustering Updates
3. Networking Updates
4. Filesystems and Storage updates
5. Desktop Updates
6. Tools Updates
7. Architecture Specific Support
8. Kernel Updates

Official Release Notes:

http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5.4/html-single/Release_Notes/

Technical Notes can be read thru:

http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5.4/html/Technical_Notes/

Copyright belongs to Red Hat, Inc..