Configure Sendmail as a Smarthost and rewriting the from-address

  1. Install both the sendmail and sendmail-cf packages on your Redhat/CentOs server.  Use the command: yum install sendmail sendmail-cf 
  2. To automatically start sendmail to start on system boot we issue the command: chkconfig sendmail on 
  3. To start sendmail NOW we issue the command: service sendmail start 

Creating a Centralized Syslog Server

A centralized syslog server was one of the first true SysAdmin tasks that I was given as a Linux Administrator way back in 1997. My boss at the time wanted to pull in log files from various appliances and have me use regexp to search them for certain key words. At the time Linux was still in its infancy, and I had just been dabbling with it in my free time. So, I jumped at the chance to introduce Linux to the company that I had worked for. Did it work? You bet it did!

How to Fix a "JVM terminated. Exit code=13" Error in Eclipse

    • First, realize that this error is caused when you are attempting to start Eclipse using the wrong version of the Java Virtual Machine (JVM). So you need to realize what JVM you are starting with.
    • If you are using Linux, you can type "which java" on the command line. Otherwise, you can type "java -version". This will give you the Java version.

How to use Logical Volume Manager (LVM) to grow etx4 file systems online

One aspect of moving towards a highly available, always up system is being able to add space to a server without having to shutdown the applications and without having to unmount file systems. 

LVM and ext4 combined are a giant leap to being able to run mission critical applications on Linux systems.

Dell PowerEdge Server, Windows 2003 x64, and the Battle Over SAS RAID Drivers

It seemed like a simple enough task – Install Windows Server 2003 R2 Standard on a Dell PowerEdge 860.The server contains four 73GB SAS drives plugged into an internal PERC 5/i SAS RAID controller.The problem started out being that the Windows installer didn’t see the system’s hard drives during the setup process.

Fix for Windows Server 2003 Setup No OEM Drivers

Fix for Windows Server 2003 Setup error: “Setup could not find a floppy drive on your machine to load OEM driver from floppy disk”

Windows Server 2003 R2 32-bit setup error when specifying additional storage drivers:

“Setup could not find a floppy drive on your machine to load OEM driver from floppy disk

Press ESC to Cancel loading OEM Drivers
Press F3 to quit setup”

This error occured when trying to install Windows Server 2003 R2 onto a Dell PowerEdge 830 server with a Dell CERC SATA 1.5/6ch RAID controller card.

Recover/Reset Windows 2003 Server Active Directory Administrator Password

This article assumes that you forgot the AD admin password, someone changed it on you, or you are recovering from an attack.

This is not meant as a how to hack your company’s Active Directory – nope, not in any way, shape, or form. In case you decide to use this tutorial for nefarious purposes, we can not be held liable for your stupidity. With that said let’s move on.

If you are trying to recover a local admin password from Windows XP, Vista, 2000, or NT, please refer to last week’s article on how to reset you local admin password.

Using openssl to convert CA certificates to different types

PEM Format

The PEM format is the most common format that Certificate Authorities issue certificates in. PEM certificates usually have extentions such as .pem, .crt, .cer, and .key. They are Base64 encoded ASCII files and contain "-----BEGIN CERTIFICATE-----" and "-----END CERTIFICATE-----" statements. Server certificates, intermediate certificates, and private keys can all be put into the PEM format.

Secure LDAP in an Active Directory Environment

By default, the Microsoft LDAP implementation does not support secure LDAP. To setup secure LDAP using SSL, certificates must be installed on both sides, the LDAP Server and LDAP Client. In this case, the LDAP Server is the domain controller running Active Directory. The LDAP Client is the UMRA software, either the UMRA Console application or the UMRA Service.

The certificates required to run secure LDAP using SSL can be configured in many ways. The concept is always the same:

Install Open Source VMware Tools on Red Hat Enterprise/CentOS Linux 6

Install Open Source VMware Tools on Red Hat Enterprise/CentOS Linux 6 VMware makes a repository available for us to install the VMware tools for a variety of Linux distributions including Red Hat, CentOS, and Ubuntu.

This example will show an install VMware tools on a Red Hat Enterprise/CentOS Linux 6 guest running on a VMware ESXi/ESX 4.1 or 5.1 host.

First import the VMware repository GPG signing public keys:


Subscribe to RSS