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Red Hat Enterprise Linux 5.2 Released

Red Hat enterprise Linux version 5.2 has been released and available via a Red Hat Network subscription. This update brings broad refresh of hardware support and improved quality, combined with new features and enhancements in areas such as virtualization, desktop, networking, storage & clustering and security.

Virtualization of very large systems, with up to 64 CPUs and 512 GB of memory, is now possible. Virtualization support for NUMA-based architectures is provided, as well as security, performance, manageability and robustness improvements. CPU frequency scaling support for virtualized environments also allows for reduced power consumption.

Red Hat Enterprise Linux 5.2 provides enhanced capabilities for several hardware architectures, covering x86/x86-64, Itanium, IBM POWER and IBM System z, which provide improved performance, power usage, scalability and manageability. For example, support for Intel's Dynamic Acceleration Technology permits power saving by quiescing idle CPU cores, and offers performance gains by potentially overclocking busy cores within safe thermal levels. Other hardware enhancements include extensive device driver updates, covering storage, network and graphics devices, and certification of IBM's new Cell Blade systems.

Red Hat Enterprise Linux becomes a certified operating system for IBM's new high-performance blade server based on Cell Broadband Engine (Cell/B.E) Architecture.

Desktop version includes latest cutting edge softwares:

  • Evolution 2.12.3
  • Firefox 3
  • OpenOffice 2.3.0
  • Thunderbird 2.0

Red Hat Cluster Suite, which is included in Red Hat Enterprise Linux 5 Advanced Platform, now has a Resource Event Scripting Language that enables sophisticated application failover capabilities. It also newly supports SCSI-3 reservation fencing support for active/active and active/passive DM/MPIO (multipathing), which widens the range of storage devices that can be used in clusters.

Improved iSCSI support allows users to set-up diskless systems with a root volume on the iSCSI server, a common requirement in high-density Blade environments.


How do I upgrade my system?

First, make sure you backup existing configuration and data. Next, simply type the following two commands:
# yum update
# reboot

Verify that everything is working fine including all services:
# netstat -tulpn
# netstat -nat
# tail -f /var/log/messages
# egrep -i 'error|warn' /var/log/messages
# egrep -i 'error|warn' /path/to/apps/log/file

Alternatively, you can click on the "Red Hat Network Alert Notification GUI Tool" - which is a notifier that appears on the panel and alerts users when software package updates are available for the systems. This is point and click method.

If you are CentOS Linux user wait for some time to get all updates. More information available at Red Hat web site.

Powertop is Linux tool to find out what is using power on a laptop. This program only works on Intel based laptops. It is very good software to extend Laptop battery life time. I've tested this software with following Intel based laptops:
=> My Sony VAIO Laptop
=> My Dell 6400 Laptop
=> My office HP / Compaq Laptop

From the project page:

Computer programs can make your computer use more power. PowerTOP is a Linux tool that helps you find those programs that are misbehaving while your computer is idle.

PowerTOP combines various sources of information from the kernel into one convenient screen so that you can see how well your system is doing at saving power, and which components are the biggest problems.

PowerTOP has these four basic goals:

=> Show how well your system is using the various hardware power-saving features
=> Show you the culprit software components that are preventing optimal usage of your hardware power savings
=> Help Linux developers test their application and achieve optimal behavior
=> Provide you with tuning suggestions to achieve low power consumption

Quick PowerTOP installation

Type the following commands:
$ sudo apt-get install powertop
$ sudo powetop

PowerTOP ~ Save and Extend Linux Laptop Battery
(Fig. 01: PowerTop in Action [ Image Credit Intel Corp / Powertop Project] )

Download PowerTOP

=> Visit official project home page to grab PowerTOP software.

This is a reader contributed article.

These days almost all server / laptop / desktop system has a gigabit Ethernet card (NIC) pre installed. Most servers are directly connected to internet using 100Mbps connections. You can save real power on your Linux server or desktop by operating at 100Mbps Ethernet speed. For example 1 gigabit link is going to consume more power than the power used at 100Mbps speed. Also note that not all systems actually use gigabit speed. For example my desktop system only used for browsing or chatting purpose or Linux web server used to display just static web pages. Now just calculate power consumption for 100 servers or 1000 desktop systems. Bottom line use Gigabit Ethernet speeds only when needed. Did you know - you can save 2 watts or more per Linux/UNIX/Windows server/desktop by just setting a correct speed :)

See current Ethernet card speed

Use ethtool comment to display current speed:
ethtool eth0 | grep -i speed

Set new speed and save power

Following command will set card speed to 100Mbps:
ethtool -s eth0 autoneg off speed 100

=> For more information see ethtool command and network interface speed, duplex . auto negotiate settings on Linux

About the author: Rocky Jr., is an engineer with VSNL - a leading ISP / global telecom company in India and a good friend of nixCraft.