I am in the process of setting up a box for someone and I thought I’d document the software RAID portion of it a little bit, in case it is helpful to anyone else.
I’m a bit of a command line junkie so it should come as no surprise then that I prefer to setup my software RAID sets using the command line tools available. The system in question this time is a newly installed CentOS 5 box. In this article I’ll concentrate on creating a mirrored set.
After loosing a hard drive I thought it was time to look into upgrading a little bit. At home I run two systems 24×7 to take care of a couple of things. One provides me with a place to do the little bit of freelance work that I do. It’s an old Dell server running Fedora Core 6 on a single 40GB drive. The other one runs Ubuntu and is my MythTV/file server and is the system that lost the drive.
As I explained in a previous post, the plan is to replace the four 80GB drives with a pair if mirrored 500GB drives. I’d also like to cut back on the number of running systems in the house so this box will also either host my dev work directly on Fedora 8 or, by using XEN, run another instance of Fedora 8. I’m hoping that the new setup will still provide me with the network speeds I’m used to from the Mac Mini (~42MB/s) and provide the services I’ve grown used to while using less power. I usually look down upon the idea of spending money to save money but with one less machine running and three fewer drives spinning I should come out ahead by a good margin.
Late last week I found out that I had lost a drive in my striped RAID array. I had four 80GB drives setup as a striped set for speed. The array stored things like ripped DVDs, music, downloads and most importantly any video that I was editing on my Mac. I knew the risks of going RAID0 so I had backups of my most important stuff but it’s still a loss in time all the same.
I was originally using the four drives in a RAID5 set but performance was too slow for editing when combined with gigabit speeds. I also needed the space at the time. To replace the drive, I actually decided to replace all of the hardware as well. I’ll be moving from a P4 3.0Ghz to a Core 2 Duo 2.2Ghz with 800Mhz front side bus. There are quicker options out there but this will certainly be an upgrade from what I have, while using less power most likely.
For drives I’ve ordered a pair of Samsung 500GB drives which I’ll mirror. I didn’t really feel shorted on space before so 500GB will still feel like an upgrade and I’ll be able to take advantage of mirroring to help protect the data to some extent.
I have an online photo album that, when a file is uploaded, will create a thumbnail size and an intermediate sized photo along with the full size version. I needed to copy the full size version of the file out while skipping the thumb and sized versions. I was able to accomplish this task using a single command:
[[email protected] Wedding]# for I in `ls | grep -v sized | grep -v thumb`; do cp $I /var/www/html/pics/; done
This would have taken a lot longer using any other method. Using a GUI, say, Windows Explorer, I’d still be selecting which files to copy by the time the above command completed the work.
Recently on digg.com there was a list of UNIX/Linux commands every person should know. A few people were a bit miffed that the list included nano rather than VIM. VIM is easily my favorite text editor so I wanted to share some of the most useful commands that VIM provides. No doubt there are people out there that have their own set of commands they use most so I encourage them to comment about it.
Read on to learn more about VIM.
I’ve been a Linux user for a long time, eight years in fact. Now I’m not trying to toot my horn, I merely am pointing out that I’ve been around long enough to see a lot of changes and a number of flash-in-the-pan distributions come and go. Most of the time the short lived distributions were simply repackaged and re-branded versions of an existing Linux project like Red Hat or whatever and they were pretty easy to pick up. Everything looked and felt like a Red Hat system but this “new” distribution focused on a certain aspect. Mandrake Linux or Linux Mandrake as it might been more commonly called back then, was in fact based on Red Hat but with an experience more focused on KDE and ease of use. Today of course Mandrake is known as Mandriva and you can no longer say that it is simply a repackaged Red Hat (or Fedora) distribution.
Now like I said, I’ve been using Linux as a desktop or server OS since about 1999, probably longer than a lot of people. During that time I pretty much have used Red Hat (or Fedora Core) exclusively and I’ve grown accustomed to it’s inner workings. I don’t have to reference anything to know how to install packages, what packages are called, manage services, edit config files or what have you, it’s all just familiar territory. Much like walking around my house in the dark, there are no surprises anymore.
I found this on Digg.com and it’s completely beyond me how people can be so clueless and still make comments. It’s people like this that create false fear, false assumptions and everything else that is dragging technology and fair use down.
While reading a debate on a ZDNet blog concerning Linux vs. Windows, this “interesting” character came along. I figured everyone could use a good chuckle and a reminder of some of the thinking we are up against. Enjoy.
read more | digg story
The Linux community has been saying it for years, “this is the year of Linux on the desktop” and each time I wrote it off as wishful thinking. For a number of years I felt Linux had never really made any real progress, just changes. I said things like, the things that were good in Linux 5 years ago are still good now, and everything that sucked about Linux 5 years ago still sucks today. You have your old timer applications and services like Apache that are just as rock solid today as they’ve ever been but then some projects like GNOME have felt unfinished.
I’m not much of a TV watcher yet I appreciate devices like the TiVO and DVRs and have always wanted one. The problem is, sometimes I’m really cheap, I don’t want to pay for a TiVO and I really don’t want to pay a recurring fee just to get a program guide. Being the techie geek I am I also want to be able to watch recorded TV shows on other devices and again, pay nothing for it.
MythTV to the rescue. (http://mythtv.org)
MythTV has existed for a number of years now and I’ve given it a try multiple times. Each time I gave up on it any one of a few reasons and it usually could have been resolved by throwing more money at the project. I usually hit two snags with my MythTV setup. One of the reasons was, where do I put a loud computer that isn’t too far away to hook up to the TV (for those times when I *did* want to watch a show on the TV) but most of the time it was because I didn’t have enough computing power to do transcoding, better known as, the ability to pause live TV. This was a real bummer to me because it’s one of the key features of any DVR, any VCR can record a TV show, but only a DVR can pause live TV.