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Colourful man pages
4 days, 7 hours ago
Linux man pages are the most important resource for a Linux freak. By default man pages are formatted using the ‘less’ utility. ‘less’ shows the man pages in black & white, something like this : -
Bash Parameter Expansion
1 week, 1 day ago
If you use bash you already know what Parameter Expansion is, although you may have used it without knowing its name. Anytime you use a dollar sign followed by a variable name you're doing what bash calls Parameter expansion, eg echo $a or a=$b. But parameter expansion has numerous other forms which allow you to expand a parameter and modify the value or substitute other values in the expansion process. -
Installing Linux apps: A few good tips
2 weeks ago
Under Linux, installing new applications isn't a particularly hard task, but installations do come in several different varieties, so it's worth understanding the differences and what you'll need to know to make them work. -
Change Volume From a Bash Script
2 weeks, 1 day ago
If you use ALSA for sound on your system the functions contained in the script presented here can be used to get and set the volume on your system. You might use this if you had a monitoring script running and wanted to raise the volume when you signal an alarm and then lower it again to the previous volume. -
36 Items To Capture For Practical Hardware Asset Tracking
1 month, 3 weeks ago
If you are managing more than one equipment in your organization, it is very important to document and track ALL information about the servers effectively. In this article, I have listed 36 attributes that needs to be tracked for your equipments, with an explanation on why it needs to be tracked. I have also provided a spreadsheet template with these fields that will give you a jumpstart. -
Floating Point Math in Bash, Part 2 (Wait for System Load)
1 month, 3 weeks ago
If you run scripts that require a lot of execution time it's a good idea to try to avoid letting them overload your system. You can run them via nice, but if for example your script is sending a bunch of emails your email daemon isn't running via nice and it may itself get out of control. One way to deal with this is by using the values in /proc/loadavg to pause when your system load gets too high. -
10 Ultimate Rules for Effective System Administration
2 months, 1 week ago
The following 10 items are guidelines more than rules, that I have learned over the years doing intensive work on the IT infrastructure. These guidelines are mostly common sense and can be helpful for anybody who administers an IT system, including Linux/Windows Administrator, Network Administrator and DBA. -
Network monitoring with Zenoss: A reluctant administrator's guide
2 months, 2 weeks ago
My wife and I have been using (and collecting) computers for years. Now my household now has four physical computers, one of them dual boot. All are on a single internal local area network with five real users plus sundry administrative ones on each. Some of the computers are also running services. I also have two computers sitting in a box, which will probably be added to this mess soon, plus my wife plans to get a laptop. I now manage a network bigger than many small businesses! But I can’t afford to pay a system administrator, and the tedium of “network plumbing” is my least favorite part of computer technology. Surely, there must be a way to automate this mess? Enter Zenoss. -
10 ways to make Linux boot faster
2 months, 2 weeks ago
Linux rarely needs to be rebooted, but when it does, it’s often slow to boot. Fortunately, there are ways to speed things up. Some of these methods are not terribly difficult (although some, unfortunately, are). -
Linux answers the age-old question, "Why is my network slow?"
2 months, 2 weeks ago
For every person who has said, "Let's network these two computers" there are many more asking "Why is the network running so slow?" Yet, the ethereal nature of Ethernet has long made computer networks hard to decipher and many a business or home user has longed to peek into the data stream to see just what is going on. You could pay tens of thousands of dollars for the answer -- but we'll do it using freely available tools for Linux. -
The Mess That is Linux Volume Management
2 months, 2 weeks ago
The GNU/Linux operating system is blessed to have sound partition management tools like GParted which are very easy to use. However, when it comes to the management of 'virtual partitions' known as volumes, things are quite different. There is Linx Volume Management, or LVM for short, however it can only really be used from the command line. Also, it doesn't integrate software RAID - except for striping. I was quite optimistic when I started using volume management some four years ago, but not anymore. Let me explain why I'm disappointed. -
Lazy Linux: 10 essential tricks for admins
2 months, 3 weeks ago
Learn these 10 tricks and you'll be the most powerful Linux systems administrator in the universe. Well, maybe not the universe, but you will need these tips to play in the big leagues. Learn about SSH tunnels, VNC, password recovery, console spying, and more. Examples accompany each trick, so you can duplicate them on your own systems. -
Setting up DRBD in an open source SAN
2 months, 3 weeks ago
Open source storage area networks need to be configured for replicated storage. This tip explains how to do so with the Distributed Replicated Block Device, or DRBD. -
Creating an installation server for SUSE Linux Enterprise Server
2 months, 3 weeks ago
When installing multiple SUSE Linux Enterprise servers, using an installation server can facilitate the process. This tip details how to create an installation server for SLES 10. -
Face off: Windows vs. Linux real world RAM and disk tests
2 months, 3 weeks ago
How do Windows Vista and Linux really compare against each other? It’s one thing to talk about the familiar applications available to Windows users contrasted with the rich suite of free open source apps for Linux, but something totally different to actually compare the loads of the two operating systems as they perform functionally identical tasks. - More News
Linux.com : System Administration
Monitor your network with GroundWork Monitor Community Edition
A reliable network monitoring and management solution must accurately detect network devices such as routers, servers, and client workstations. It must be able to display a map of the whole network, monitor the health and performance of each device, and have a way to notify someone of a problem by email, text message, or other form of communication. It should be able to fix a problem by restarting services or running specific programs. It should generate detailed reports that you can analyze easily to help prevent future incidents. Finally, a decent monitoring system must be easy to use, deploy, and customize according to your monitoring needs. Let's use these standards to see if GroundWork Monitor Community Edition is up to the task.
Clean up your filesystems with fslint
Maintaining filesystems can be a real administration burden. Over time you might start getting multiple copies of the same file, soft links that point to files that no longer exist, temporary files that have been hanging around longer than they should, and binaries that have been installed and not had their debugging information stripped out. fslint can help you find these troublesome files so you can clean up your filesystem.
Protect your network with pfSense firewall/router
pfSense is a free, powerful firewall and routing application that allows you to expand your network without compromising its security. Started in 2004 as a child project of m0n0wall -- a security project that focuses on embedded systems -- pfSense has had more than 1 million downloads and is used to protect networks of all sizes, from home offices to large enterprises. pfSense has an active development community, and more features are being added in each release to further improve its flexibility, scalability, and, of course, security.
Sbopkg provides seamless package repository integration for Slackware
No Linux distribution can bundle every package that users might want, so most distros host software repositories from which users can download and install additional applications. Since 2006 Slackbuilds.org has served as a high-quality repository for Slackware users, but using it requires several steps and switching between a Web browser and a virtual terminal. Sbopkg is a new ncurses-based utility that helps users build packages from SlackBuilds.org and seamlessly integrates the repository with the operating system.
Simplify system security with the Uncomplicated Firewall
The Uncomplicated Firewall (UFW) is a new tool from Ubuntu whose goal is to make configuration of the built-in Linux packet filter less complicated and more secure for novice users.
Devil-Linux distro bundles router/firewall and server in one live CD
Devil-Linux might sound hellish for a Linux distribution, but this live CD offers many blessings for your server needs. Originally developed as a router/firewall distribution, Devil-Linux has expanded its functionality to include nearly every service that a server might offer. It can function as an LDAP server, a VPN server, an email or file server, and more.
Process monitoring with ps-watcher
You can monitor your computers in a wide variety of ways. Large proprietary applications make sense for large installations that can afford the expense of both the software and consultants who fine-tune the systems. Open source monitoring solutions like Nagios or OpenNMS cost nothing to acquire but still require planning and tweaking. When you need to address smaller problems with process data on a system, the process monitoring tool ps-watcher comes in handy.
Securing your network with PacketFence
Network access control (NAC) aims to unify endpoint security, system authentication, and security enforcement in a more intelligent network access solution than simple firewalls. NAC ensures that every workstation accessing the network conforms to a security policy and can take remedial actions on workstations if necessary. For example, NACs can check if a workstation has antivirus software installed and, if not, NAC will limit the workstation's access to the network. In some cases, if NAC is capable of remedial measures, it can force-install an antivirus program on the workstation so that it will conform to the security policy. Although NAC can improve the security of your environment, most commercial NACs cost several thousand dollars. However, using NAC does not need to be that expensive. PacketFence, a free open source NAC application, gives you the security of NAC for free.
Umit, the graphical network scanner
Umit is a user-friendly graphical interface to Nmap that lets you perform network port scanning. The utility's most useful features are its stored scan profiles and the ability to search and compare saved network scans. A profile lets you configure how a network scan is performed, change the source information for the scan, and explicitly nominate hosts to include or exclude from the scan, as well as various more advanced options.
Get thin client benefits for free with openThinClient
Thin clients reduce hardware costs, offer added security by stripping away storage options, and ease management tasks by storing all configurations on a centralized server. Citrix provides a good solution and is a dominant player in this arena with Citrix Presentation server, but that comes at a price -- about $1,000 for five concurrent connections and about $200 to $300 for each additional concurrent client connection. However, taking the thin client route does not have to be that expensive: openThinClient is an open source thin client server that is absolutely free.
Implement load-balancing, port forwarding, and rate-limiting with shd-tcp-tools
shd-tcp-tools provides a collection of tools for port forwarding, load balancing, and rate-limiting TCP connections. They can be useful if you want to offer SSH services but also limit how much of your bandwidth each user can consume, so that a single long-running SCP operation cannot starve the link from your server to the Internet.
A comparative look at compact sysadmin distributions
Things go wrong. Hard disks fail and whole servers crash. Luckily, many Linux-based distributions are available to help systems administrators handle minor catastrophes. We looked at four of the most portable, all of which fit on a 210MB mini CD -- SliTaz, Parted Magic, GParted, and RIPLinuX.
What UUIDs can do for you
If you've ever looked in your /etc/fstab file, you have may have seen an entry that looks like UUID=62fa5eac-3df4-448d-a576-916dd5b432f2 instead of a more familiar disk drive designation, such as /dev/hda1. Such entries are called universally unique identifiers (UUID). You can use these 128-bit numbers to make hard disk management easier.
Cook up tasty custom Ubuntu live CDs with UCK
Live CDs let you boot an operating system without installing any software on a hard drive. There are plenty of Linux live CDs and lots of tools to customize them. The Ubuntu Customization Kit, tastefully called UCK, lets you add your favorite applications into the distro. If you're not happy with the factory-installed Ubuntu apps, here's your chance to spin up your very own Ubuntu live CD without too much effort.
Kernel tuning with sysctl
The Linux kernel is flexible, and you can even modify the way it works on the fly by dynamically changing some of its parameters, thanks to the sysctl command. Sysctl provides an interface that allows you to examine and change several hundred kernel parameters in Linux or BSD. Changes take effect immediately, and there's even a way to make them persist after a reboot. By using sysctl judiciously, you can optimize your box without having to recompile your kernel, and get the results immediately.
Use LatencyTOP to find out where process latency is coming from
The latency of the execution of a particular task can be affected by what tasks a system is running, the condition of the network the machine is connected to, and how well the various server machines on the network are performing. LatencyTOP is a command-line tool and kernel patch that lets you see what is causing latency in the applications on your system.
Keep an eye on your system logs with phpLogCon
phpLogCon provides a user-friendly Web interface to your system logs. It can handle logs from both Linux and Windows systems, so an administrator can log in to a single phpLogCon site to see what is happening on all the machines on a network.
Finnix: Compact Linux distribution for system administrators
Finnix is a live CD distribution designed to assist system administrators in such tasks as system recovery and network monitoring. Based on Debian testing and Linux kernel 2.6, Finnix helps with filesystem and partition manipulation as well as with data recovery, installation of other operating systems, and boot record repair.
Taming your daemons with PSMon
The PSMon utility lets you specify which processes should be running, how much of resources such as CPU or RAM each is allowed to use when it runs, and how many instances are able to be run. PSMon will then ensure that these processes are running and kill off a process if it starts to use too many resources, and possibly restart a process if it has crashed.
phpMinAdmin is a powerful minimalist MySQL editor
If you've ever worked with and manipulated MySQL databases, chances are you've used phpMyAdmin to manage your databases from a Web interface. But phpMyAdmin can be a little complex; if you want a lightweight alternative, try phpMinAdmin. It's easier to install than its more robust cousin and has an easy-to-navigate graphical user interface for most important MySQL functions.
