As an IT manager, there are a lot of things you can do which directly impact your company’s bottom line. While the most obvious are direct hardware and software costs, an often overlooked aspect is energy/electricity consumption by computer systems. While servers need to be available 24/7, desktop systems only need to be available when the respective user needs it or for scheduled maintenance tasks. The rest of the time (usually more than 50% of the time), the system can stay in low power mode which reduces power usage, hence cost.
If you want to quickly see what processes are wasting all of your memory, you can do so with a simple command line that filters the output from ps to sort by memory usage, and return only the ten biggest memory hogs.
If you’ve got a web application that uploads files to the server through a PHP script, you might have noticed that by default you can’t upload terribly large files. Here’s how to change it.
All Dell servers come with the Dell OpenManage Server Administrator software which has the ability to monitor and display system level indicators. Additionally, through the Alert Management tab you can configure actions to execute whenever an alert is triggered. Unfortunately there is no vehicle for applying uniform notifications to all events, so we are going to provide a script which configures all the alert actions to send an email notifying you of the respective event. While you could set these up manually, having a script is ideal as you can easily deploy this across multiple servers.
Linux has a rich set of commands for manipulating and accessing files. The du utility gives information on disk usage, and the sort utility can sort the results. Finally, we can run those results through the head command, which gives you the top 10 lines outputted through any other command. We’ll chain the commands together to get the output that we want.
Unless you have a special setup, you typically only need a single IP address from your ISP to run your network. With your network sitting behind a firewall/router, you can direct your incoming traffic to the appropriate servers to handle email, web, remote connections and anything else. The problem comes when you have multiple servers which need to receive traffic from a common port. Instead of adding more public IP addresses (and cost), we are going to show you how to handle this situation using on a single IP.
Have you ever used a tail -f on a logfile, only to find that it’s scrolling by way too fast for you to deal with? If you know exactly what you’re looking for, you can always grep the contents, but often you aren’t sure what you need to see. In this case, it’s useful to reverse grep instead.
Changing the group a user is associated to is a fairly easy task, but not everybody knows the commands, especially to add a user to a secondary group. We’ll walk through all the scenarios for you.
A common function of many programs is the ability to send email. When working on development projects or doing product demos which utilize email, having an environment you know will work can be critical. For these situations, having a completely self contained email system, that is all emails “sent” never leave the local machine, is the answer.
This page will explain how to renew your DHCP address when using Linux.
When you get a dedicated virtual server to run your website, chances are good that it’s configured for everybody, and not customized to maximize performance for running a website.
If you want to move all files of a particular file type into a single directory, you can use the find command to do this easily in Linux.
If you can’t stand the automatic hyperlinking in Microsoft Word, you might be hard-pressed to find the right place to disable it in Office 2007, since all the settings are hidden so well compared to previous versions.
If you are getting the following error while trying to change the default fat32 partition on a new drive to another linux partition type, I might have the answer for you.
If you get this error in your logs when trying to setup public key authenticated automatic logins, the problem is a permissions one.
If you’ve ever needed to change the hostname for Red Hat Linux, CentOS or similar operating systems, you can do so easily with one simple command.
Remote Desktop Connection is a useful feature in Windows that allows you to log on and view the desktop of another computer via your internet connection from your own computer. This article will explain how to use your local drives during a Remote Desktop session.
If you want to setup SSH keys to allow logging in without a password, you can do so with a single command.
This article will cover how to use the port-forwarding feature in SSH to accomplish tunneling from one machine to another.
If you’ve moved an Ubuntu virtual machine or modified it and then suddenly had a problem getting networking to work, you might want to read through this page, because I’ve figured out a workaround to get it working again.
If you’ve used the GUI tool to share a folder with your Ubuntu guest machine, you probably are confused why it’s not showing up anywhere.
This page will explain how you can use ISO image files in Linux.
This page will show us how to create a list of files and folders ordered by size using standard Linux commands.
Have you ever needed to quickly share a folder with another machine? Rather than deal with samba, nfs, or apache, you can just run a simple command instead.
If you are getting this error then you probably reset the permissions on your hidden .ssh directory in your user folder, and your keys aren’t going to work anymore. It’s very important that these files not be writable by just anybody with a login to the box, so openssh will give you an error if you try to use them.