Archive for the ‘Linux’ Category

Increasing a virtual machine's disk space

Monday, August 17th, 2009 by tburns

I run linux, primarily. When I need access to a Windows workstation, I use a virtual machine on VmWare-Server v.2.0. I have an XP build that, originally, had a single, 10 GB C:\ partition. I have installed lots of stuff on it including some pretty hefty Cisco and Windows applications and I was running out of space. I needed to increase the size of the partition without breaking anything, so I used a couple of nifty tools to do it.

First of all, be sure to backup your virtual machine files. You should do that anyway… I have multiple, pocket-sized external hard drives that I use for on-the-fly backups. I also have some larger, powered drives that I use at home for mega backups. Disk space is cheap. Why skimp?
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Installing and configuring a wireless card

Saturday, August 15th, 2009 by tburns

Installing a wireless card in linux is a breeze these days. I have a Fedora 10 build. Here’s how I did it (Most of these tasks need to be done as root):

1. Find out how your machine recognizes your wireless card. Do a simple lspci to be sure you can see the card:

[root@localserver ~]#lspci
...
09:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5752 Gigabit Ethernet PCI Express (rev 02)
0c:00.0 Network controller: Broadcom Corporation BCM4312 802.11a/b/g (rev 01)
...

I got a lot more output than that, but the only thing I am concerned with here are my network cards. In particular, the BCM4312 entry.
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iTunes, VmWare, and Samba

Sunday, July 5th, 2009 by tburns

I have multiple machines that have multiple purposes but I only have one iPhone. I’ve put all my iTunes files/mp3s on a network samba share to avoid having them limited to one local, bare-metal Windows build. It’s just too tough to get to when your primary machines all run some flavor of linux. I have used external hard drives to manage these files before, but I found that to be a lot more work than simply configuring a virtual machine to manage the iTunes application and a network share to manage its content. I keep the virtual machine on an external hard drive that I back up regularly and that is available to every laptop/desktop that I have that runs VmWare.

To install this on a virtual machine, I had to move my iTunes build. I wanted also to preserve all my iTunes Playlists. I’d put together all these collections and I wasn’t willing to give them up. Here are the details on moving it all while keeping your playlists. Make note that this doesn’t result in an exact one-for-one cloned copy of iTunes. You lose several key features/elements:

– You lose the time/date stamps on the files within iTunes. This means, when you open it up, all the files have the same ‘Date Added’ date. This is a problem if you have a Recently Added folder because, when you’re done, that folder will hold everything;
- You lose all your column formatting. So, if you have a specific way you like to view/browse your collection, you’ll have to re-organize it manually; and
- You lose all the data in your iPhone Apps. The Apps themselves are able to be salvaged and re-sync’d, but the data will be gone.
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Tracking down malicious code on a linux box

Wednesday, March 11th, 2009 by tburns

This blog site uses a WordPress theme called Blue Zinfandel developed by a guy named Brian Gardner. When I first launched it, I spent several days looking for something I liked and found and downloaded this from – I have no idea where…

Yesterday I discovered malicious code had been inserted into the header.php file. I should have been more careful… but I wasn’t, and I had to spend a few hours tracking down the offending code and cleaning it up. Here’s what happened:

First, the environment: I run this site on a virtualized Fedora box anchored to Xen and hosted by linode.com. I built a customized iptables script to filter traffic and can select incoming and outgoing traffic through a series of 1s and 0s and a quick redeploy. For example, I have a list of variables that can be assigned for client function and a list that can be assigned for server function.
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Renicing processes for better performance

Friday, February 27th, 2009 by tburns

I was asked to write a script that could be run from cron that would prioritize processes running on an application server running Oracle Unbreakable Linux v.5. The intention was to increase application performance.

I wrote a simple script to ‘re-nice’ select processes. Nice and Renice operate on the principal that the lower the value of the process (the scale is from -20 to +19), the higher the priority the process has on CPU time. In other words, a process that is nice to others, is +19. One that isn’t so nice is at -20. In function then, a process that requires lots of immediate CPU time such as an RTP-specific application running voice-related services (as was the case in this example), may benefit from running at a higher priority (thus as a negative on the niceness scale) than, say, sendmail, which can queue and resend without, necessarily, a degradation in service.

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